SUMMARY

        This summary highlights selected information from this proxy statement/prospectus and may not contain all of the information that is important to you. To understand the merger fully and for a more complete description of the legal terms of the merger, you should read carefully this entire proxy statement/prospectus, including the merger agreement and the other documents to which we have referred you. See "Where You Can Find More Information" beginning on page 121. Page references are included in this summary to direct you to a more complete description of the topics.

        Throughout this proxy statement/prospectus, "FAB," refers to First Associations Bank, "Pacific Premier" refers to Pacific Premier Bancorp, Inc. and the "Bank" refers to Pacific Premier Bank, Pacific Premier's banking subsidiary. Also, throughout this proxy statement/prospectus, the Agreement and Plan of Reorganization, dated as of October 15, 2012, among Pacific Premier, the Bank and FAB, is referred to as the "merger agreement." The merger between FAB and a wholly owned subsidiary of the Bank is referred to as the "subsidiary merger," and the subsequent merger and liquidation of FAB with and into the Bank is referred to as the "bank merger." The subsidiary merger and the bank merger together are referred to as the "merger."

Parties to the Proposed Merger (Page 75)

        Pacific Premier Bancorp, Inc.    Pacific Premier is a California-based bank holding company for the Bank, a California-chartered commercial bank. Pacific Premier's principal asset is all of the capital stock of the Bank. The Bank conducts business throughout Southern California from its ten locations in the cities of San Bernardino, Seal Beach, Huntington Beach, Los Alamitos, Irvine, Newport Beach, Palm Springs and Palm Desert, California. The Bank provides banking services within its targeted markets in Southern California to businesses, professionals, real estate investors and non-profit organizations, as well as consumers in the communities it serves. Through the Bank's branches and its Internet website at www.ppbi.com, the Bank offers a broad array of deposit and loan products and services for both businesses and consumer customers. As of September 30, 2012, Pacific Premier had, on a consolidated basis, total assets of $1.1 billion, total stockholders' equity of $99.9 million and total deposits of $895.9 million. At September 30, 2012, Pacific Premier had real estate loans and business loans collateralized by real estate totaling 76.6% of its gross loan portfolio.

        Based on information contained in Schedule 13Ds, Schedule 13Gs and Schedule 13Fs filed with the Commission, there are seven shareholders (including five institutional shareholders) who collectively beneficially own an aggregate of approximately 27.2% of Pacific Premier's outstanding common stock. These seven shareholders, together with the shares of Pacific Premier common stock beneficially owned by Steven Gardner, Pacific Premier's president and chief executive officer, beneficially own an aggregate of approximately 29.5% of Pacific Premier's outstanding common stock. Pacific Premier is not aware of any agreements, arrangements or understandings between such shareholders with respect to the voting or disposition of any shares of Pacific Premier common stock. The 3,795,000 shares of Pacific Premier common stock issued in connection with its recent public offering of common stock are included in the calculation of these aggregate beneficial ownership percentages.

        Other than as publicly disclosed in their respective Schedule 13Ds, Schedule 13Gs or Schedule 13Fs filed with the Commission, Pacific Premier is not aware of any increase or decrease in the beneficial ownership of these seven shareholders, including as a result of the shares of common stock sold in Pacific Premier's recently completed public offering. To the extent that any of these seven shareholders purchased additional shares of Pacific Premier common stock in the offering or purchased or sold shares of Pacific Premier common stock in the open market, through privately negotiated transactions or otherwise, their collective beneficial ownership of shares of Pacific Premier's common stock could have changed from the percentages provided above.

Recent Developments Involving Pacific Premier

        On December 11, 2012, Pacific Premier completed an underwritten public offering of 3,300,000 shares of its common stock at a public offering price of $10.00 per share, and on January 9, 2013 Pacific Premier issued an additional 495,000 shares of its common stock at a public offering price of $10.00 per share in connection with the underwriters' exercise of the over-allotment option granted to them as part of the offering. The net proceeds from the offering, including the underwriters' exercise of the over-allotment option, after deducting underwriting discounts and commissions and estimated offering expenses were approximately $35.6 million. Pacific Premier intends to use the net proceeds of this offering for general corporate purposes, to support its ongoing and future anticipated growth and to augment the capitalization of the Bank. As of the date of this proxy statement/prospectus, the net proceeds from this offering have not been applied for any specific purpose other than being available to Pacific Premier and the Bank for general corporate purposes.

        Pacific Premier's principal executive offices are located at 17901 Von Karman Ave., Suite 1200, Irvine, California 92614 and its telephone number is (714) 431-4000.

        First Associations Bank.    FAB is a commercial bank that is exclusively focused on providing deposit and other services to homeowners associations, or HOAs, and HOA management companies nationwide. In providing the deposit services to HOAs and HOA management companies, FAB utilizes online technology tools that provide HOA management companies the ability to streamline their operations through data integration and seamless information reporting to their HOAs. FAB's deposit and treasury management products for HOAs include web based funds management, online automated clearing house, or ACH, services, online homeowner payment options, integrated third party lockbox services and remote deposit capture. FAB also offers term loans for projects undertaken by the HOA and lines of credit for short term or seasonal needs of HOAs. FAB does not accept retail or consumer deposits or provide other lending or other more traditional banking services to consumers or other type of commercial customers. The provision of financial services to HOAs and HOA management companies is highly competitive. FAB competes nationwide with a number of other financial institutions that provide banking services for HOA management companies and HOAs.

        FAB operates out of its headquarters in Dallas, Texas, which is its sole office. At September 30, 2012, FAB had total assets of $356.2 million, which was comprised of total investment securities of $313.9 million and total net loans of $18.6 million, total stockholders' equity of $45.9 million and total deposits of $305.5 million.

The Merger (Page 38)

        The merger agreement is attached to this proxy statement/prospectus as Appendix A, which is incorporated by reference into this proxy statement/prospectus. Please read the entire merger agreement. It is the legal document that governs the merger. Pursuant to the terms and conditions set forth in the merger agreement, FAB will be acquired by Pacific Premier in a two step transaction whereby FAB will ultimately merge with and into the Bank, with the Bank as the surviving institution. The first step consists of the subsidiary merger, in which a newly formed and wholly owned Texas-chartered subsidiary of the Bank, PPBI Interim Corporation, or Merger Subsidiary, will merge with and into FAB, with FAB as the surviving entity. Following the subsidiary merger, FAB will be a subsidiary of Pacific Premier for a moment in time before the second step of the transaction is completed. The bank merger will be the second step of the transaction, in which FAB will merge with and liquidate into the Bank, with the Bank as the surviving institution. The parties expect to complete the merger in the first quarter of 2013.

FAB's Reasons for Merger and Factors Considered by FAB's Board of Directors (Page 40)

        Based on FAB's reasons for the merger described herein, including the fairness opinion of SAMCO Capital Markets, Inc., or SAMCO, an independent investment banking firm, the FAB board of directors believes that the merger is fair to FAB shareholders and in their best interests, and unanimously recommends that FAB shareholders vote "FOR" approval of the merger agreement. For a discussion of the circumstances surrounding the merger and the factors considered by FAB's board of directors in approving the merger agreement, see page 40.

Pacific Premier's Reasons for Merger (Page 41)

        As part of Pacific Premier's business strategy, Pacific Premier evaluates opportunities to acquire bank holding companies, banks and other financial institutions. The acquisition of FAB is consistent with this strategy. Pacific Premier believes that the acquisition of FAB will generate additional revenue by leveraging the FAB deposit funding model and the Bank's commerical banking business model, create synergies as a result of the HOA customer base of FAB, improve and strengthen the Bank's deposit base, and allow Pacific Premier to utilize a portion of its capital to acquire FAB.

FAB's Financial Advisor Believes that the Merger Consideration is Fair, From a Financial Point of View, to FAB Shareholders (Page 42)

        SAMCO delivered its written opinion to FAB's board of directors that, as of October 11, 2012, and based upon and subject to the factors and assumptions set forth in the opinion, the merger consideration to be received by the holders of the outstanding FAB common stock pursuant to the merger agreement was fair from a financial point of view to such holders.

        The full text of the written opinion of SAMCO, dated October 11, 2012, which sets forth assumptions made, procedures followed, matters considered and limitations and qualifications on the review undertaken in connection with the opinion, is attached as Appendix B to this proxy statement/prospectus. FAB's shareholders should read the opinion in its entirety. SAMCO provided its opinion for the information and assistance of FAB's board of directors in connection with its consideration of the transaction. The SAMCO opinion does not address the underlying business decision to proceed with the merger and is not a recommendation as to how any holder of FAB common stock should vote or make any election with respect to the merger agreement or any related matter.

        FAB engaged the services of SAMCO as its exclusive financial advisor in June 2012 for the primary purpose of identifying a potential strategic merger partner, which led to contacting Pacific Premier in August 2012 and eventually entering into the merger agreement. Pursuant to the terms of SAMCO's engagement as financial advisor and other advisory services, FAB agreed to pay SAMCO (i) upon consummation of the merger, an amount equal to 1.0% of the aggregate merger consideration, plus consideration paid regarding outstanding or cashed out options, warrants or rights to purchase shares as of the date of the merger agreement, plus the value of the contingent payments to be received, including payments to executive personnel, plus any extraordinary dividends or distributions paid on or prior to the merger's closing and (ii), upon delivering the opinion, a $10,000 fee for providing the fairness opinion, plus an additional $15,000 upon closing of the merger. As of the date of this proxy statement/prospectus, FAB has paid $10,000 in fees to SAMCO in connection with the merger. FAB estimates that the remaining fee payable to SAMCO in connection with the merger will be approximately $582,000, which assumes aggregate merger consideration of $51.2 million is paid to FAB shareholders, an aggregate of $3.5 million is paid to holders of FAB stock options and FAB warrants and an aggregate of $2.25 million is paid to officers and directors of FAB in consideration for their respective non-compete and non-solicitation covenants with Pacific Premier in connection with the merger.

FAB Shareholders Will Receive a Cash Payment in Exchange for Each Share of FAB Common Stock and Whole Shares of Pacific Premier Common Stock (Page 48)

        At the effective time of the merger, each outstanding share of FAB common stock (subject to certain exceptions) will, by virtue of the merger and without any action on the part of a FAB shareholder, be converted into the right to receive the per share cash consideration and the per share stock consideration, each of which is described below. The aggregate per share cash consideration together with the aggregate per share stock consideration is referred to as the merger consideration. Upon completion of the merger, $51.2 million of merger consideration will be payable to the FAB shareholders, or $25.84 per share of FAB common stock, which assumes the per share cash consideration is not adjusted and is therefore $19.00, the implied value of the per share stock consideration is $6.84 (based on the closing price per share of Pacific Premier's common stock on January 11, 2013) and that there are 1,980,229 shares of FAB common stock outstanding. Upon completion of the merger, and based on 1,980,229 shares of FAB common stock outstanding as of the date of this proxy statement/prospectus, FAB shareholders are expected to receive 1,279,228 shares of Pacific Premier common stock. Following the completion of the merger, and based on 14,156,648 shares of Pacific Premier common stock outstanding as of January 11, 2013, the former FAB shareholders will own approximately 8.3% of the outstanding shares of Pacific Premier common stock and the current shareholders of Pacific Premier will own the remaining approximately 91.7% of the outstanding shares of Pacific Premier common stock.

        Per Share Cash Consideration.    As part of the merger consideration, holders of FAB common stock will be entitled to receive a cash payment in exchange for each share of FAB common stock. The per share cash consideration will be calculated upon consummation of the merger by taking the sum of (i) $19.00 and (ii) the amount equal to the quotient of (A) the increase or decrease in the sum of (1) the aggregate realized gains (net of any losses) on the sale of any or all of FAB's mortgage-related securities portfolio that occur between the date of the merger agreement and the closing date of the merger and (2) the unrealized gains or losses on FAB's mortgage-related securities portfolio through the month-end prior to closing of the merger that are greater or less than $4,577,406, excluding any subsequent gains realized and included in subclause (1), divided by (B) the number of issued and outstanding shares of FAB common stock. For purposes of the formula used to calculate the per share cash consideration in accordance with the merger agreement, the value of the unrealized gains in the FAB mortgage-related securities portfolio as of August 31, 2012 was used, which unrealized gains amounted to $4,577,406. The FAB mortgage-related securities portfolio is comprised of government agency-issued mortgage-backed securities and collateralized mortgage obligations, which securities have an aggregate duration of approximately 2.2 years. As of August 31, 2012, the FAB mortgage-related securities portfolio was valued at $192,199,340, which was comprised of $141,827,766 of government agency-issued mortgage-backed securities and $50,371,575 of government agency-issued collateralized mortgage obligations. As of January     , 2013, the latest practicable date before the filing of this proxy statement/prospectus, the FAB mortgage-related securities portfolio was valued at $            , which was comprised of $            of government agency-issued mortgage-backed securities and $            of government agency-issued collateralized mortgage obligations.

        The cash portion of the merger consideration is subject to change and will depend on the realized and unrealized gains and losses on FAB's mortgage-related securities between the date of the merger agreement as of the closing date of the merger. In addition, the per share cash consideration is subject to downward adjustment if FAB's aggregate transaction-related expenses exceed $3.9 million, with any excess reducing the per share cash consideration by the quotient of (i) such excess amount divided by (ii) the total number of shares of issued and outstanding FAB common stock. Under the terms of the merger agreement, FAB's transaction-related expenses consist of FAB's accounting, legal and advisory fees (including an estimated $592,000 fee payable to SAMCO), termination fees associated with third party vendor contracts and an aggregate of $2.25 million payable to FAB executive officers, FAB board

members and a FAB advisory board member for their respective non-compete and non-solicitation covenants. Because the cash portion of the merger consideration is subject to adjustment, the amount of cash consideration to be received will not be known at the time you vote on the merger agreement.

        To the extent that no adjustment to the cash consideration occurs as a result of unrealized gains or losses on the FAB mortgage-related securities portfolio between the date of the merger agreement and the closing date of the merger or as a result of the transaction-related expenses and assuming that there are 1,980,229 shares of FAB common stock issued and outstanding, the cash portion of the merger consideration would be $37,624,351, or $19.00 for each share of FAB common stock.

        To the extent that there are realized or unrealized gains or losses with respect to FAB's mortgage-related securities portfolio between the signing of the merger agreement and the closing of the merger which exceed or are less than $4,577,406, the cash portion of the merger consideration will be adjusted accordingly. As of December 31, 2012, FAB had unrealized gains of approximately $1,951,232 on its mortgage-related securities portfolio and, as of January 11, 2013, which is the latest practicable date before the filing of this proxy statement/prospectus, FAB had realized gains from the sale of its mortgage-related securities in its portfolio of approximately $2,343,250. Based on these amounts, FAB would have had an aggregate amount of unrealized and realized gains of $4,294,482 which, when applying the formula for calculating the per share cash consideration as provided in the merger agreement, would have resulted in a per share cash consideration of $18.86 for each share of FAB common stock. This calculation of the per share merger consideration assumes no reduction in the cash portion of the merger consideration for transaction-related expenses.

        To illustrate how further changes in the value of FAB's mortgage-related securities portfolio would impact the per share cash consideration, for each $100,000 of realized or unrealized gains on the FAB mortgage-related securities portfolio that occur between the signing of the merger agreement and the closing of the merger, if any, holders of FAB common stock will receive an additional $0.05 per share of FAB common stock. Similarly, for each $100,000 of realized or unrealized losses on the FAB mortgage-related securities portfolio that occur between the signing of the merger agreement and the closing of the merger, if any, the per share cash consideration received by holders of FAB common stock will be reduced by $0.05 per share of FAB common stock.

        Per Share Stock Consideration.    As part of the merger consideration, holders of FAB common stock also will be entitled to receive Pacific Premier common stock in exchange for their shares of FAB common stock. The exchange ratio for each share of FAB common stock is fixed at 0.646 of a share of Pacific Premier common stock, which is the per share stock consideration. Because the exchange ratio for the stock portion of the merger consideration is fixed, the implied value will fluctuate based on the market price of Pacific Premier common stock and will not be known at the time you vote on the merger agreement. The value implied by the per share stock consideration exchange ratio for one share of FAB common stock on January 11, 2013 was $6.84, based on the closing price per share of Pacific Premier common stock on that date, which was the last practicable trading-day before the filing of this proxy statement/prospectus. Pacific Premier's common stock is listed on the Nasdaq Global Market under the symbol "PPBI."

Merger Consideration Example

        As discussed above, the merger consideration to be received by FAB shareholders will be subject to change and likely fluctuate prior to closing based on the amount of realized and unrealized gains, if any, on securities in FAB's mortgage-related securities portfolio, as well as the future market value of Pacific Premier common stock. Assuming for illustrative purposes only that the merger closed on January 11, 2013, FAB realizing gains on the sale of securities in its mortgage-related securities portfolio of $2,343,250 as of that date and the value of the unrealized gains of the securities remaining in FAB's mortgage-related securities portfolio as of December 31, 2012, the month end prior to the

assumed closing date, of approximately $1,951,232, the aggregate realized and unrealized gains on the FAB mortgage-related securities portfolio for purposes of calculating the per share cash consideration would be approximately $4,294,482. Based on these unrealized and realized gains on FAB's mortgage-related securities and assuming no reduction in the per share cash consideration for transaction-related expenses, the amount of the per share cash consideration would have been $18.86 for each share of FAB common stock.

        To illustrate the calculation of the per share cash consideration based on the assumed amounts of unrealized and realized gains in the FAB mortgage-related securities portfolio described above, the following formulaic example is provided:

        If the closing stock price of Pacific Premier common stock was $10.59 per share on the closing date, which was the closing price of Pacific Premier's common stock on January 11, 2013, then the implied value for the per share stock consideration on that date would be $6.84 based on the fixed exchange ratio of 0.646 of a share of Pacific Premier common stock for each share of FAB common stock.

        Based on these assumptions, the combined per share merger consideration payable for each share of FAB common stock would be valued at $25.70.

        FAB shareholders should be aware that the above per share amounts are estimates only and are based on the assumptions indicated. There is no assurance that the level of realized and unrealized gains included in the example achieved, if any, or that the market price of the Pacific Premier common stock will not decrease prior to the closing. Therefore, the actual value of the per share merger consideration that each FAB shareholder will receive in exchange for its FAB common stock may be more, less or the same as this example above.

        No fractional shares of Pacific Premier common stock will be issued, and in lieu thereof, each holder of FAB common stock who would otherwise be entitled to a fractional share interest will receive an amount in cash, without interest, determined by multiplying such fractional interest by $9.80, which amount reflects the average closing price of Pacific Premier common stock for the five (5) trading days prior to signing the merger agreement, rounded to the nearest whole cent.

What Will Happen to Outstanding FAB Stock Options and Warrants (Page 51)

        Each outstanding stock option to acquire shares of FAB common stock, or FAB stock option, and each outstanding warrant to purchase shares of FAB common stock, or FAB warrant, that is vested and unexercised immediately prior to consummation of merger will be canceled in exchange for the right to receive a cash payment from Pacific Premier or the Bank. The aggregate cash payment for all of the FAB stock options and FAB warrants is approximately $3.5 million.

        The cash payment for the cancellation of each vested and outstanding FAB stock option and FAB warrant is fixed pursuant to the merger agreement. The amount payable for each FAB stock option and FAB warrant is based on a fixed per share merger consideration of $25.33, less the applicable exercise price for the FAB stock option or FAB warrant, and then adding a tax gross up amount (which is intended to compensate holders of FAB stock options and FAB warrants for the less favorable income tax treatment afforded to them as compared to shareholders of a subchapter-"S" corporation, such as FAB). The fixed per share merger consideration of $25.33 reflects an assumed $19.00 per share cash consideration, plus an assumed $6.33 per share stock consideration, which was the value of 0.646 share of Pacific Premier common stock based on the average closing price of Pacific Premier common stock for the five (5) trading days prior to signing the merger agreement. For example, each FAB stock option and FAB warrant with an exercise price of $10.00 per share will entitle the holder to receive

$23.23, which amount was calculated by taking the sum of (i) the difference between (A) $25.33 and (B) $10.00 (the exercise price) plus (ii) $7.90 (the calculated tax gross up amount). All of the FAB warrants, which are held by directors of FAB and are exercisable for 64,564 shares of FAB common stock, have an exercise price of $10.00 per share. As of the date of this proxy statement/prospectus, there were 96,000 FAB stock options outstanding, of which 70,000 FAB stock options have an exercise price of $10.00 per share, with the remaining 26,000 FAB stock options having exercise prices of $12.00, $16.00 or $17.00 per share. The officers of FAB hold an aggregate of 80,000 FAB stock options. See "The Merger—FAB Options and Warrants" and "The Merger—Interests of Certain FAB Officers and Directors in the Merger" in this proxy statement/prospectus for more information. In addition to the tax gross up payment described above, the cash payment by Pacific Premier in consideration for the cancellation of the FAB stock options and FAB warrants is different than the merger consideration to be paid to FAB shareholders for their FAB common stock, since the payment for each FAB stock option and FAB warrant is fixed and will not be subject to either upward or downward adjustment and is payable in all cash. In contrast, the aggregate value of the merger consideration to be paid to the holders of FAB common stock will vary, depending on the value of the FAB mortgage-related securities portfolio, whether transaction-related expenses exceed $3.9 million and changes in the stock price of Pacific Premier common stock.

Shareholders Should Wait to Surrender their FAB Common Stock Certificates (Page 52)

        At least thirty (30) days prior to the closing of the merger (or such later date mutually agreed to by Pacific Premier and FAB), FAB shareholders or, if applicable, the record holder of the shares of FAB common stock, will be sent a letter of transmittal advising of the proposed effective date of the merger and instructions for surrendering certificates representing shares of FAB common stock in exchange for the merger consideration payable to FAB shareholders. The letter of transmittal should be completed and returned to American Stock Transfer and Trust Company, or the exchange agent, along with your stock certificates representing shares of FAB common stock. After the letter of transmittal and certificates have been received and the letter of transmittal processed, FAB shareholders will be sent the number of whole shares of Pacific Premier common stock and the amount of cash consideration to which FAB shareholders are entitled, in each case without interest. If any FAB shareholders hold shares in street name, he or she will receive information from his or her broker or other holder of record advising of the process for receiving the per share stock consideration and per share cash consideration to which he or she is entitled.

        FAB shareholders will need to surrender their FAB common stock certificates prior to receiving the merger consideration, but should not send FAB any certificates now. FAB shareholders will receive detailed instructions on how to exchange their shares of FAB common stock along with their letter of transmittal.

Per Share Market Price and Dividend Information (Page 74)

        Shares of Pacific Premier common stock currently trade on the Nasdaq Global Market under the symbol "PPBI." FAB common stock is not listed on an exchange or quoted on any automated services, and there is no established trading market for shares of FAB common stock. The table below sets forth the closing sale prices of Pacific Premier common stock as reported on the Nasdaq Stock Market on October 15, 2012, the last trading-day before the merger was announced, and on January       , 2013, the last practicable trading-day before the filing of this proxy statement/prospectus.

        To help illustrate the market value of the stock portion of the merger consideration to be received by FAB's shareholders, the following table also presents the equivalent market value per share of FAB common stock on October 15, 2012 and January       , 2013, which were determined by multiplying the closing price of the Pacific Premier common stock on those dates by the exchange ratio of 0.646 of a share of Pacific Premier common stock for each share of FAB common stock. The equivalent market

value per share of FAB common stock presented below does not reflect the per share cash consideration that also will be received by holders of FAB common stock.

        The market price of Pacific Premier common stock will fluctuate prior to the merger. FAB shareholders should obtain a current price quotation for the shares of Pacific Premier common stock.

        Pacific Premier has never declared or paid dividends on its common stock and does not anticipate declaring or paying any cash dividends in the foreseeable future. It is Pacific Premier's current policy to retain earnings to provide funds for use in its business.

        FAB historically has paid dividends on its common stock that serve as "tax distributions" related to its status as an S corporation. These "tax distributions" are designed to provide FAB shareholders with funds to enable them to pay the federal income taxes on their pro rata portion of FAB's taxable net income.

Material Federal Income Tax Consequences of the Merger (Page 67)

        The exchange of FAB common stock for Pacific Premier common stock and cash pursuant to the merger will be a taxable transaction for U.S. federal income tax purposes. Accordingly, a U.S. Holder (as defined in "The Merger—Material Federal Income Tax Consequences") of FAB common stock who receives Pacific Premier common stock and cash in exchange for such U.S. Holder's shares of FAB common stock generally will recognize taxable gain or loss in an amount equal to the difference, if any, between the sum of the fair market value of the Pacific Premier common stock and cash received and such U.S. Holder's adjusted tax basis in the shares of FAB common stock exchanged therefor. Such gain or loss will constitute capital gain or loss, and will constitute long-term capital gain or loss if the U.S. Holder's holding period for the FAB common stock exchanged is greater than one year as of the date such U.S. Holder's FAB common stock is exchanged pursuant to the merger.

        Tax matters are complicated, and the tax consequences of the merger to a particular FAB shareholder will depend in part on such shareholder's individual circumstances. Accordingly, FAB shareholders are advised to consult their own tax advisors for a full understanding of the tax consequences of the merger to them, including the applicability and effect of federal, state, local and foreign income and other tax laws.

Date, Time and Location of the Special Meeting (Page 34)

        The special meeting will be held at            .m., Central Time, on                , 2013, at the First Floor Conference Room, Coit Central Tower, 12001 North Central Expressway, Dallas, Texas 75243. At the special meeting, FAB shareholders will be asked to:

•

approve the merger agreement; and



•

approve a proposal to adjourn the special meeting if necessary to permit further solicitation of proxies if there are not sufficient votes at the time of the special meeting to approve the merger agreement.

Record Date and Voting Rights for the Special Meeting (Page 35)

        Each FAB shareholder is entitled to vote at the special meeting if he or she owned shares of FAB common stock as of the close of business on                    , 2013. Each FAB shareholder will have one vote at the special meeting for each share of FAB common stock that he or she owned on that date.

        Shareholders of record may vote by mail or by attending the special meeting and voting in person. Each proxy returned to FAB by a holder of FAB common stock, which is not revoked, will be voted in accordance with the instructions indicated thereon. If no instructions are indicated on a signed proxy that is returned, such proxy will be voted "FOR" approval of the merger agreement and "FOR" the proposal to adjourn the special meeting if necessary to permit further solicitation of proxies on the proposal to approve the merger agreement.

Approval of the Merger Agreement Requires the Affirmative Vote of Two-Thirds of the FAB Shareholders (Page 36)

        The affirmative vote of the holders of two-thirds of the outstanding shares of FAB common stock is necessary to approve the merger agreement on behalf of FAB. At the close of business on the record date, there were 1,980,229 shares of FAB common stock outstanding held by 78 holders of record. Each holder of record of FAB common stock on the record date is entitled to one vote for each share held on all matters to be voted upon at the special meeting. If a FAB shareholder does not vote, it will have the same effect as a vote against the merger agreement.

        Holders of 708,255 shares of FAB common stock, representing approximately 36.0% of the outstanding shares of FAB common stock, have signed shareholder agreements with Pacific Premier agreeing to vote in favor of the merger agreement.

        Due to the structure of the merger and the number of shares of Pacific Premier common stock to be issued to FAB shareholders pursuant to the merger agreement, Pacific Premier shareholders are not required by law or Pacific Premier's amended and restated certificate of incorporation and amended and restated bylaws to adopt the merger agreement or approve the merger or the issuance of the Pacific Premier common stock in connection with the merger.

Management of FAB Owns Shares Which May Be Voted at the Special Meeting (Page 70)

        As of the record date, the executive officers and directors of FAB and an advisory director of FAB, as a group, held 708,255 shares of FAB common stock, or approximately 36% of the outstanding FAB common stock and have each entered into shareholder agreements with Pacific Premier and FAB pursuant to which they have agreed, among other things, in their capacity as shareholders of FAB, to vote their shares of FAB common stock in favor of the merger agreement. The form of shareholder agreement is attached as Annex A to the merger agreement, which is attached as Appendix A to this proxy statement/prospectus.

FAB's Shareholders Have Dissenters' Rights (Page 71)

        Under the Texas Business Organizations Code, or TBOC, holders of FAB common stock have the right to demand appraisal of their shares of FAB common stock in connection with the merger and to receive, in lieu of the merger consideration, payment in cash, for the fair value of their shares of FAB common stock. Any shareholder electing to exercise dissenters' rights must vote against the merger proposal and must comply with the provisions of the TBOC in order to perfect its rights of dissent and appraisal. Strict compliance with the statutory procedures is required to perfect dissenters' rights. These procedures are described later in this proxy statement/prospectus, and a copy of the relevant provisions of Texas law is attached as Appendix C.

FAB is Prohibited from Soliciting Other Offers (Page 59)

        FAB has agreed that, while the merger is pending, it will not solicit, initiate, encourage or engage in discussions with any third party other than Pacific Premier regarding extraordinary transactions such as a merger, business combination or sale of a material amount of assets or capital stock.

Pacific Premier and FAB Must Meet Several Conditions to Complete the Merger (Page 53)

        Completion of the merger depends on meeting a number of conditions, including the following:

•

shareholders of FAB must approve the merger agreement;



•

Pacific Premier and FAB must receive all required regulatory approvals for the merger, and any waiting periods required by law must have passed and no such approval may contain any condition that Pacific Premier's board of directors reasonably determines in good faith would materially reduce the benefits of the merger to such a degree that, had such condition been known, Pacific Premier would not have entered into the merger agreement;



•

there must be no law, injunction or order enacted or issued preventing completion of the merger;



•

the Pacific Premier common stock to be issued in the merger must have been approved for trading on the Nasdaq Global Market;



•

the representations and warranties of each of Pacific Premier and FAB in the merger agreement must be true and correct, subject to the materiality standards provided in the merger agreement;



•

Pacific Premier and FAB must have complied in all material respects with their respective obligations in the merger agreement;



•

the employment agreements entered into between the Bank and the key executive officers of FAB must not have been terminated and remain in full force and effect;



•

as of the closing date, FAB's average total deposits during a specified period and Tier 1 capital must not be less than $313,360,617.90 and $36,786,292.65, respectively;



•

the Depository Services Agreement, dated October 1, 2011, as amended, or the Depository Services Agreement, between FAB and Associations, Inc., or Associa, must be amended in the form attached as Annex E to the merger agreement; and



•

dissenting shares must not represent 10% or more of the outstanding shares of FAB common stock.

        Unless prohibited by law, either Pacific Premier or FAB could elect to waive a condition that has not been satisfied and complete the merger anyway. The parties cannot be certain whether or when any of the conditions to the merger will be satisfied, or waived where permissible, or that the merger will be completed.

Pacific Premier and FAB Have Received Regulatory Approvals to Complete the Merger (Page 55)

        To complete the merger, the parties need the prior approval of or waiver from the Board of Governors of the Federal Reserve System, or the Federal Reserve, the California Department of Financial Institutions, or CA DFI, and the Texas Department of Banking, or the TDB. Pacific Premier and FAB have received approval from each of the banking regulators for the merger and a waiver from the Federal Reserve from the application requirements under the Bank Holding Company Act of 1956, as amended, or BHC Act.

Pacific Premier, the Bank and FAB may Terminate the Merger Agreement (Page 61)

        Pacific Premier, the Bank and FAB can mutually agree at any time to terminate the merger agreement before completing the merger, even if shareholders of FAB have already voted to approve it.

        Pacific Premier and the Bank on one hand or FAB on the other hand can also terminate the merger agreement:

•

if the other party breaches any of its representations, warranties, covenants or agreements under the merger agreement that (i) cannot be or has not been cured within thirty (30) days of the giving of written notice to the breaching party or parties and (ii) would entitle the non-breaching party or parties not to consummate the merger;



•

if the merger is not consummated by March 31, 2013, except to the extent that the failure to consummate by that date is due to (i) the terminating party's failure to perform or observe its covenants and agreements in the merger agreement, or (ii) the failure of any of the FAB shareholders (if FAB is the party seeking to terminate) to perform or observe their respective covenants under the relevant shareholder agreement; or



•

if any required governmental approval of the merger has been denied by final non-appealable action or an application for approval of the merger has been permanently withdrawn at the request of a governmental authority, provided that no party has the right to terminate the merger agreement if the denial is due to the terminating party's failure to perform or observe its covenants in the merger agreement.

        In addition, Pacific Premier and the Bank may terminate the merger agreement if the shareholders of FAB do not approve the merger agreement.

Pacific Premier, the Bank and FAB May Amend the Merger Agreement (Page 61)

        The parties may amend or supplement the merger agreement by written agreement at any time before the merger actually takes place; provided, however, no amendment may be made after the special meeting which by law requires further approval by the shareholders of FAB without obtaining such approval.

FAB's Directors and Officers Have Some Interests in the Merger that Are in Addition to or Different than Your Interests (Page 62)

        FAB's directors and officers have interests in the merger as individuals that are in addition to, or different from, their interests as shareholders of FAB, which are:

•

the employment agreements the Bank entered into with each of Michael Kowalski, Greg Smith and Cathleen Coltrell in connection with the signing of the merger agreement, which will become effective upon consummation of the merger. Each of the employment agreements provides for non-competition and non-solicitation covenants that Messrs. Kowalski and Smith and Ms. Coltrell agreed to. As consideration for their respective non-competition and non-solicitation covenants, Messrs. Kowalski and Smith and Ms. Coltrell will receive a cash payment in the amount of $250,000, $250,000 and $200,000, respectively, in connection with their employment with the Bank as of the closing of the merger;



•

the officers of FAB hold outstanding FAB stock options and the directors of FAB hold FAB warrants that will be canceled in connection with the closing of the merger in exchange for the right to receive a cash payment from Pacific Premier or the Bank. The aggregate cash payment for all of the FAB stock options and FAB warrants held by FAB's directors and officers is approximately $3.2 million. The amount payable for each FAB stock option and FAB warrant is based on a fixed per share merger consideration of $25.33, less the applicable exercise price for

the FAB stock option or FAB warrant, and then adding a tax gross up amount (which is intended to compensate the holders of FAB stock options and FAB warrants for the less favorable income tax treatment afforded to them when compared to shareholders of a subchapter-S corporation, such as FAB). Accordingly, since all vested FAB stock options and FAB warrants held by FAB directors and executive officers had an exercise price of $10.00, each such holder will be entitled to receive for the cancellation of each FAB stock option and FAB warrant $23.23, which amount was calculated by taking the sum of (i) the difference between (A) $25.33 and (B) $10.00 (the exercise price) plus (ii) a $7.90 (the calculated tax gross up amount). In addition to the tax gross up payment described above, the cash payment by Pacific Premier in consideration for the cancellation of the FAB stock options and FAB warrants is different than the merger consideration to be paid to FAB shareholders for their FAB common stock, since the payment for each FAB stock option and FAB warrant is fixed and will not be subject to either upward or downward adjustment and is payable in all cash. In contrast, the aggregate value of the merger consideration to be paid to the holders of FAB common stock will vary, depending on the value of the FAB mortgage-related securities portfolio, whether transaction-related expenses exceed $3.9 million and changes in the stock price of Pacific Premier common stock;

•

the shareholders agreements that Pacific Premier entered into with each of John Carona, Joe Alcantar, James Hyatt, Glenn Thurman and Joey Carona in connection with the execution of the merger agreement include non-competition and non-solicitation covenants. As consideration for their respective non-competition and non-solicitation covenants, Mr. John Carona will receive a cash payment in the amount of $1.0 million, each of Messrs. Alcantar, Hyatt and Thurman will receive a cash payment in the amount of $150,000 and Mr. Joey Carona will receive a cash payment in the amount of $100,000 payable as of the closing of the merger;



•

each of Michael Kowalski and Greg Smith has a deferred compensation agreement with FAB that enables them to save for retirement on a tax deferred basis, which agreements will be terminated by FAB in connection with a change in control of FAB. The merger qualifies as a change in control under these agreements and FAB will terminate the deferred compensation agreements in connection with the closing of the merger, which will result in Messrs. Kowalski and Smith receiving lump sum amounts of $686,428 and $185,773, respectively;



•

the remaining $40,000 of Cathleen Coltrell's signing bonus will become payable upon the closing of the merger pursuant to the terms of Ms. Coltrell's employment letter with FAB;



•

the agreement of Pacific Premier to appoint John Carona, a current director of FAB and the Chief Executive Officer and majority owner of Associa, to serve on the boards of directors of Pacific Premier and the Bank following completion of the merger; and



•

the agreement of Pacific Premier to honor indemnification obligations of FAB for a period of six (6) years, as well as to purchase liability insurance for FAB's directors and officers for three (3) years following the merger, subject to the terms of the merger agreement.

        The aggregate cash amount payable to the FAB officers, the FAB directors and a FAB advisory director in connection with the consummation of the merger is approximately $5.5 million. The three largest cash payments that will be made to officers and directors of FAB upon completion of the merger are approximately:

•

$1.4 million to Mr. Kowalski as payment for the cancellation of his FAB stock options and FAB warrants and for his non-compete and non-solicitation covenants in his employment agreement with Pacific Premier;



•

$1.3 million to Mr. John Carona as payment for the cancellation of his FAB warrants and for his non-compete and non-solicitation covenants; and

•

$715,000 to Mr. Smith as payment for the cancellation of his FAB stock options and for his non-compete and non-solicitation covenants in his employment agreement with Pacific Premier.

        The cash payments that will be made to Messrs. Kowalski and Smith exclude the deferred compensation payments described in the fourth bullet point above because these amounts consist solely of compensation previously earned by each of them. To the extent that FAB's transaction-related expenses exceed $3.9 million and the cash portion of the merger consideration is reduced by such excess, the payments made to the FAB officers, the FAB directors and the FAB advisory director for their respective non-compete and non-solicitation covenants will have the effect of reducing the merger consideration payable to FAB shareholders because these payments are included in FAB's transaction-related expenses.

        The board of directors of FAB was aware of the foregoing interests and considered them, among other matters, in approving the merger agreement and the merger.

Accounting Treatment of the Merger (Page 69)

        The merger will be accounted for under the purchase method of accounting under generally accepted accounting principles, or GAAP.

Shareholders of Pacific Premier and FAB Have Different Rights (Page 112)

        The rights of shareholders of Pacific Premier differ from the rights of shareholders of FAB. Pacific Premier is incorporated under the laws of the State of Delaware and FAB is incorporated under the laws of the State of Texas. The rights of holders of Pacific Premier common stock are governed by the Delaware General Corporation Law, or DGCL, as well as its amended and restated certificate of incorporation and amended and restated bylaws, and the rights of holders of FAB common stock are governed by the Texas Finance Code and the TBOC, as well as its amended articles of association and bylaws. Upon consummation of the merger, shareholders of FAB will receive shares of Pacific Premier common stock in exchange for their shares of FAB common stock and become shareholders of Pacific Premier and their rights as shareholders of Pacific Premier will be governed by Pacific Premier's amended and restated certificate of incorporation and amended and restated bylaws and the DGCL.

SELECTED HISTORICAL FINANCIAL DATA

        The following tables present selected consolidated historical financial data of Pacific Premier and selected historical financial data of FAB.

Selected Consolidated Historical Financial Data of Pacific Premier

        Set forth below are selected historical financial data derived from Pacific Premier's audited consolidated financial statements as of and for the years ended December 31, 2011, 2010, 2009, 2008 and 2007 and Pacific Premier's unaudited interim consolidated financial statements as of and for the nine months ended September 30, 2012 and 2011. The results of operations for the nine months ended September 30, 2012 are not necessarily indicative of the results of operations for the full year or any other interim period and, in the opinion of Pacific Premier's management, this information reflects all adjustments, consisting of only normal recurring adjustments, necessary for a fair presentation of this data for those dates. You should read the information set forth below together with Pacific Premier's consolidated financial statements and related notes included in Pacific Premier's Annual Report on Form 10-K for the year ended December 31, 2011 and Quarterly Report on Form 10-Q for the quarter ended September 30, 2012. Pacific Premier's Annual Report on Form 10-K for the year ended December 31, 2011 was filed with the Commission on March 30, 2012 and its Quarterly Report on Form 10-Q for the quarter ended September 30, 2012 was filed with the Commission on November 8, 2012. Both reports are incorporated by reference in this document. See "Where You Can Find More Information" beginning on page 121.

        On December 11, 2012, Pacific Premier completed an underwritten public offering of 3,300,000 shares of its common stock at a public offering price of $10.00 per share, and on January 9, 2013, Pacific Premier issued an additional 495,000 shares of its common stock at a public offering price of $10.00 per share in connection with the underwriters' exercise of the over-allotment option granted to them as part of the offering. The net proceeds from the offering, including the underwriters' exercise of the over-allotment option, after deducting underwriting discounts and commissions and estimated offering expenses, were approximately $35.6 million. The selected historical financial data in the table below does not reflect the shares of common stock issued or the net proceeds received by Pacific Premier in connection with this offering. See "Summary—Selected Unaudited Pro Forma Financial Data Reflecting Proposed Merger and Recent Offering" on page 26 and "Unaudited Pro Forma Combined Consolidated Financial Data" beginning on page 102.

Selected Historical Financial Data of FAB

        Set forth below are selected historical financial data derived from FAB's audited financial statements as of and for the years ended December 31, 2011 and 2010 and FAB's unaudited financial data as of and for the nine months ended September 30, 2012 and 2011. The results of operations for the nine months ended September 30, 2012 are derived from FAB's unaudited interim financial statements and are not necessarily indicative of the results of operations for the full year or any other interim period. In the opinion of FAB's management, this information reflects all adjustments, consisting of only normal recurring adjustments, necessary for a fair presentation of this data for those dates.

        FAB shareholders should read this information in conjunction with the section of this proxy statement/prospectus entitled "Management's Discussion and Analysis of Financial Condition and Results of Operations of FAB" beginning on page 79 and the audited financial statements and the unaudited interim financial statements of FAB which appear in this proxy statement/prospectus following the "Index to FAB Financial Statements" beginning on page F-1. The historical results presented in the following summary do not necessarily indicate expected results for future periods.