EXHIBIT 10.5

AWARD AGREEMENT

Under The

Barrett Business Services, Inc.

2015 Stock Incentive Plan

NONQUALIFIED STOCK OPTION

Corporation maintains the Barrett Business Services, Inc., 2015 Stock Incentive Plan (the “Plan”).

This Award Agreement evidences the grant of a Nonqualified Option (the “Option”) to Participant under Article 7 of the Plan.

The parties agree as follows:

When used in this Agreement, the following terms have the meaning specified below:

(a) “Acquiring Person” means any person or related person or related persons which constitute a “group” for purposes of Section 13(d) and Rule 13d-5 under the Exchange Act, as such Section and Rule are in effect as of the Grant Date; provided, however, that the term Acquiring Person shall not include (i) Corporation or any of its Subsidiaries, (ii) any employee benefit plan of Corporation or any of its Subsidiaries, (iii) any entity holding voting capital stock of Corporation for or pursuant to the terms of any such employee benefit plan, or (iv) any person or group solely because such person or group has voting power with respect to capital stock of Corporation arising from a revocable proxy or consent given in response to a public proxy or consent solicitation made pursuant to the Exchange Act.

(b) “Change in Control” means:

(i) A change in control of Corporation of a nature that would be required to be reported in response to Item 6(e) of Schedule 14A of Regulation 14A as in effect on the Grant Date pursuant to the Exchange Act; provided that, without limitation, such a change in control shall be deemed to have occurred at such time as any Acquiring Person hereafter becomes the “beneficial owner” (as defined in Rule 13d-3 under the Exchange Act), directly or indirectly, of 40 percent or more of the combined voting power of Voting Securities; or

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(ii) During any period of 12 consecutive calendar months, individuals who at the beginning of such period constitute the Board cease for any reason to constitute at least a majority thereof unless the election, or the nomination for election, by Corporation stockholders of each new director was approved by a vote of at least a majority of the directors then in office who were directors at the beginning of the period; or

(iii) There shall be consummated (1) any consolidation or merger of Corporation in which Corporation is not the continuing or surviving corporation or pursuant to which Voting Securities would be converted into cash, securities, or other property, other than a merger of Corporation in which the holders of Voting Securities immediately prior to the merger have the same proportionate ownership of Common Stock of the surviving corporation immediately after the merger, or (2) any sale, lease, exchange, or other transfer (in one transaction or a series of related transactions) of all, or substantially all, of the assets of Corporation; or

(iv) Approval by the stockholders of Corporation of any plan or proposal for the liquidation or dissolution of Corporation.

(c) “Change in Control Date” means the first date following the Grant Date on which a Change in Control has occurred.

(d) “Employer” means Corporation or a Subsidiary of Corporation.

(e) “Grant Date” means the date the Option is granted, which is reflected as the date of this Agreement.

(f) “Voting Securities” means Corporation’s issued and outstanding securities ordinarily having the right to vote at elections for director.

Capitalized terms not otherwise defined in this Agreement have the meanings given them in the Plan.

Subject to the terms and conditions of this Agreement and the Plan, Corporation grants to Participant the Option to purchase 10,000 Shares of Corporation’s common stock at $39.80 per share.

The Option is subject to all the provisions of the Plan and to the following terms and conditions:

3.1 Term. The term of the Option is ten years from the Grant Date and will automatically terminate on July 1, 2026, to the extent not exercised, unless terminated earlier in accordance with this Agreement.

3.2 Time of Exercise. Unless the Option is otherwise terminated or the time of its exercisability is accelerated in accordance with this Agreement, the Option may be exercised from time to time to purchase Shares up to the following limits (based on years after the Grant Date and including any Shares previously purchased pursuant to the Option):

(a) During the first year - none;

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(b) During the second year - up to 25 percent of the total Shares;

(c) During the third year - up to 50 percent of the total Shares;

(d) During the fourth year - up to 75 percent of the total Shares; and

(e) After the fourth year - 100 percent.

3.3 Service Requirement. Except as otherwise provided in subsection 3.4 of this Agreement, the Option may not be exercised unless Participant is employed by or serves as a Non-Employee Board Director or Non-Employee Subsidiary Director for an Employer continuously for at least one year following the Grant Date, unless employment or service is terminated by death, Disability, or Retirement. For purposes of this Agreement, “employment” and “service” include periods of illness or other leaves of absence authorized by the Employer and any transfer(s) between employee and director status (whether as a Non-Employee Board Director or Non-Employee Subsidiary Director). If Participant ceases to be an active employee or active Non-Employee Board Director or Non-Employee Subsidiary Director, the right to exercise the Option, to the extent the Option had become exercisable on or before the date of termination of service, will expire at the end of the following periods:

3.4 Acceleration of Exercisability. Notwithstanding the schedule provided in subsection 3.2, the Option will become fully exercisable (unless Participant chooses to decline accelerated Vesting of all or any portion of the Option) upon the occurrence of either:

(a) Participant’s death or termination of employment or service by reason of Disability or Retirement; or

(b) A Change in Control Date.

3.5 Method of Exercise. The Option, or any portion thereof, may be exercised, to the extent it has become exercisable pursuant to this Agreement, by delivery of written notice to Corporation stating the number of Shares, form of payment, and proposed date of closing.

3.6 Other Documents. Participant will be required to furnish to Corporation before closing such other documents or representations as Corporation may require to assure compliance with applicable laws and regulations.

3.7 Payment. The exercise price for the Shares purchased upon exercise of the Option must be paid in full at or before closing by one or a combination of the following:

(a) Payment in cash;

(b) Delivery of previously acquired Shares having a Fair Market Value equal to the exercise price;

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(c) Withholding of Shares issuable to Participant upon exercise of the Option, with a Fair Market Value on the date of delivery equal to the aggregate purchase price of the Shares as to which the Option is exercised; or

(d) Delivery (in a form approved by the Committee) of an irrevocable direction to a securities broker acceptable to the Committee:

(i) To sell Shares subject to the Option and to deliver all or a part of the sales proceeds to Corporation in payment of all or a part of the exercise price, as well as withholding taxes due, if any; or

(ii) To pledge Shares subject to the Option to the broker as security for a loan and to deliver all or a part of the loan proceeds to Corporation in payment of all or a part of the exercise price, as well as withholding taxes due, if any.

3.8 Previously Acquired Shares. Delivery of previously acquired Shares in full or partial payment for the exercise of the Option will be subject to the following conditions:

(a) The Shares tendered must be in good delivery form;

(b) The Fair Market Value of the Shares tendered, together with the amount of cash, if any, tendered must equal or exceed the exercise price of the Option;

(c) Any Shares remaining after satisfying the payment for the Option will be reissued in the same manner as the Shares tendered; and

(d) No fractional Shares will be issued and cash will not be paid to the Participant for any fractional Share value not used to satisfy the Option exercise price.

Participant will be responsible for payment of federal, state and local withholding taxes and Participant’s portion of applicable payroll taxes, if any, imposed in connection with the exercise of the Option and the issuance of Shares (collectively, the “Applicable Taxes”). Corporation’s obligation to issue Shares is expressly conditioned on Participant’s making arrangements satisfactory to Corporation, in its sole and absolute discretion, for the payment of all Applicable Taxes. Participant may satisfy his or her obligation to pay the Applicable Taxes by electing in Participant’s sole discretion (a) to pay to Corporation (in cash or by check) an amount equal to the Applicable Taxes, (b) to authorize Corporation to withhold a number of unrestricted Shares (thus reducing the number of unrestricted Shares to be issued to Participant) having a Fair Market Value (as of the Settlement Date) equal to the remaining balance of the Applicable Taxes, or (c) to authorize Corporation to withhold an amount equal to the Applicable Taxes from Participant’s payroll check or deposit to be made on or about the Settlement Date, provided such withholding is permissible under applicable state law. In no event will the amount withheld exceed the minimum amount of tax required to be withheld by law in connection with settlement of the Award.

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Corporation will not be required to issue any Shares upon exercise of the Option, or any portion thereof, until Corporation has taken any action required to comply with all applicable laws. Such action may include, without limitation, (a) registering or qualifying such Shares under any state or federal law or under the rules of any securities exchange or association, (b) satisfying any law or rule relating to the transfer of unregistered securities or demonstrating the availability of an exemption from any such law, (c) placing a restrictive legend or stop-transfer instructions on the Shares issued upon settlement of the Award, or (d) obtaining the consent or approval of any governmental or regulatory body.

Subject to restrictions on transferability set forth in the Plan, this Agreement will be binding upon and benefit the parties, their successors and assigns.

Any notices under this Agreement must be in writing and will be effective when actually delivered personally or, if mailed, when deposited as registered or certified mail directed to the address of Corporation’s records or to such other address as a party may certify by notice to the other party.

Any dispute or claim that arises out of or that relates to this Agreement or to the interpretation, breach, or enforcement of this Agreement, must be resolved by mandatory arbitration administered by and in accordance with the then effective arbitration rules of Arbitration Service of Portland, Inc. The place of arbitration will be Multnomah County, Oregon. The award rendered by the arbitrator will be final and binding, and judgment may be entered on the award in any court having jurisdiction.

In the event of any suit or action or arbitration proceeding to enforce or interpret any provision of this Agreement (or which is based on this Agreement), the prevailing party will be entitled to recover, in addition to other costs, reasonable attorney fees in connection with such suit, action, or arbitration, and in any appeal. The determination of who is the prevailing party and the amount of reasonable attorney fees to be paid to the prevailing party will be decided by the arbitrator or arbitrators (with respect to attorney fees incurred prior to and during the arbitration proceedings) and by the court or courts, including any appellate courts, in which the matter is tried, heard, or decided, including the court which hears any exceptions made to an arbitration award submitted to it for confirmation as a judgment (with respect to attorney fees incurred in such confirmation proceedings).

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Compensation paid to the Participant under this Award is subject to recoupment in accordance with any clawback policy of Corporation in effect from time to time, including any such policy adopted after the date of this Agreement, as well as any similar requirement of applicable law, including without limitation the Dodd-Frank Wall Street Reform and Consumer Protection Act and the Sarbanes-Oxley Act of 2002, and rules adopted by a governmental agency or applicable securities exchange under any such law. Participant agrees to promptly repay or return any such compensation as directed by Corporation under any such clawback policy or requirement, including the value received from a disposition of Shares acquired pursuant to this Award.

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Attachment A

NOTICE OF STOCK OPTION EXERCISE

BARRETT BUSINESS SERVICES, INC.

2015 STOCK INCENTIVE PLAN

Option:          The option evidenced by an Award Agreement dated             ,         .

OPTION EXERCISE

I hereby elect to exercise the Option to purchase shares of common stock (“Shares”) of Barrett Business Services, Inc. (“BBSI”) covered by the Option as follows:

Instructions:

(1) If payment is to be by check, a check for the amount of the Aggregate Purchase Price payable to Barrett Business Services, Inc., should be submitted with this Notice.

(2) If payment is to be by surrender of previously owned shares or by attestation of ownership (see Attestation Form below), either a certificate for the shares accompanied by a stock power endorsed in blank or the completed Attestation Form should be submitted with this Notice. If applicable, a certificate for any shares in excess of those needed to satisfy the Aggregate Purchase Price and withholding taxes, if applicable, will be returned to you with the certificate for your option shares. Any change in registration between the payment shares and the new shares will require a properly executed stock power that is guaranteed by an institution participating in a recognized medallion signature guarantee program.

(3) No withholding tax is due upon exercise of an incentive stock option. Withholding tax is due immediately upon exercise of a nonqualified option by an employee. If withholding tax is due at the time of exercise, you will be notified of the amount and satisfactory arrangements must be made for payment before a stock certificate for your option shares will be delivered to you (or your broker, if applicable). Among other alternatives, amounts necessary to satisfy withholding obligations may be deducted from compensation otherwise payable to you.

ISSUANCE INSTRUCTIONS FOR STOCK CERTIFICATES

Please register the stock certificate(s) in the following name(s):

If applicable, please check one: ¨  JT TEN    ¨  TEN COM    ¨  Other

Please deliver the stock certificate(s) to (check one):

¨  My brokerage account

¨  My mailing address set forth above.

ATTESTATION FORM

As indicated above, I have elected to use shares of BBSI common stock that I already own to pay the Aggregate Purchase Price of the Option (and withholding taxes, if applicable).

I attest to the ownership of the shares represented by the certificate(s) listed below or to the beneficial ownership of the shares held in the name of my broker, as indicated in the attached copy of my brokerage statement. I will be deemed to have delivered such shares to BBSI in connection with the exercise of my Option.

I understand that, because I (and any joint owner) will retain ownership of the shares (the “Payment Shares”) deemed delivered to pay the Aggregate Purchase Price (and withholding taxes, if applicable), the number of shares to be issued to me upon exercise of my Option will be reduced by the number of Payment Shares. I represent that I have full power to deliver and convey certificates representing the Payment Shares to BBSI and by such delivery and conveyance could have caused BBSI to become sole owner of the Payment Shares. The joint owner of the Payment Shares, if any, by signing this Form, consents to these representations and to the exercise of the Option by this attestation.

I certify that any Payment Shares originally issued to me as restricted shares are now fully vested.

List certificate(s) and number of shares covered, or attach a copy of your brokerage statement:

If you are attaching a copy of your brokerage statement, you must have your securities broker complete the following:

The undersigned hereby certifies that the foregoing attestation is correct.