Table of Contents

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

WASHINGTON, D.C. 20549

FORM 10-Q

For the Quarterly Period Ended March 31, 2014

Commission File No. 0-21886

BARRETT BUSINESS SERVICES, INC.

(Exact name of registrant as specified in its charter)

(360) 828-0700

(Registrant’s telephone number, including area code)

Indicate by check mark whether the registrant (1) has filed all reports required to be filed by Section 13 or 15(d) of the Securities Exchange Act of 1934 during the preceding 12 months (or for such shorter period that the registrant was required to file such reports), and (2) has been subject to such filing requirements for the past 90 days.    Yes  x    No  ¨

Indicate by check mark whether the registrant has submitted electronically and posted on its corporate Website, if any, every Interactive Data File required to be submitted and posted pursuant to Rule 405 of Regulation S-T (§ 232.405 of this chapter) during the preceding 12 months (or such shorter period that the registrant was required to submit and post such files).    Yes  x    No  ¨

Indicate by check mark whether the registrant is a large accelerated filer, an accelerated filer, a non-accelerated filer or a smaller reporting company (as defined in Rule 12b-2 of the Exchange Act).

Indicate by check mark whether the registrant is a shell company (as defined in Rule 12b-2 of the Exchange Act).    Yes  ¨    No  x

Number of shares of common stock, $.01 par value, outstanding at April 30, 2014 was 7,175,847 shares.

Table of Contents

BARRETT BUSINESS SERVICES, INC.

INDEX

- 2 -

Table of Contents

Part I - Financial Information

BARRETT BUSINESS SERVICES, INC.

Consolidated Balance Sheets

(Unaudited)

(In thousands, except per share amounts)

The accompanying notes are an integral part of these financial statements

- 3 -

Table of Contents

BARRETT BUSINESS SERVICES, INC.

Consolidated Statements of Operations

(Unaudited)

(In thousands, except per share amounts)

The accompanying notes are an integral part of these financial statements

- 4 -

Table of Contents

BARRETT BUSINESS SERVICES, INC.

Consolidated Statements of Comprehensive Loss

(Unaudited)

(In thousands)

The accompanying notes are an integral part of these financial statements

- 5 -

Table of Contents

BARRETT BUSINESS SERVICES, INC.

Consolidated Statements of Stockholders’ Equity

Three Months Ended March 31, 2014 and 2013

(Unaudited)

(In thousands)

The accompanying notes are an integral part of these financial statements

- 6 -

Table of Contents

BARRETT BUSINESS SERVICES, INC.

Consolidated Statements of Cash Flows

(Unaudited)

(In thousands)

The accompanying notes are an integral part of these financial statements

- 7 -

Table of Contents

BARRETT BUSINESS SERVICES, INC.

Notes to Consolidated Financial Statements (Unaudited)

Note 1 - Basis of Presentation of Interim Period Statements

The accompanying consolidated financial statements are unaudited and have been prepared by Barrett Business Services, Inc. (“Barrett”, “BBSI”, the “Company”, “our” or “we”), pursuant to the rules and regulations of the Securities and Exchange Commission. Certain information and note disclosures typically included in financial statements prepared in accordance with accounting principles generally accepted in the United States of America have been condensed or omitted pursuant to such rules and regulations. In the opinion of management, the consolidated financial statements include all adjustments, consisting only of normal recurring adjustments, necessary for a fair statement of the results for the interim periods presented. The preparation of financial statements in conformity with generally accepted accounting principles (“GAAP”) requires management to make estimates and assumptions that affect the amounts reported in the financial statements and accompanying notes. Actual results may differ from such estimates and assumptions. The consolidated financial statements should be read in conjunction with the audited financial statements and notes thereto included in the Company’s 2013 Annual Report on Form 10-K at pages F1 – F29. The results of operations for an interim period are not necessarily indicative of the results of operations for a full year.

Revenue recognition

We recognize revenue as services are rendered by our workforce. Professional employer services are normally used by organizations to satisfy ongoing human resource management needs and typically involve contracts with a minimum term of one year, which cover all employees at a particular work site. Our client services agreements are renewable on an annual basis and typically require 30 days’ written notice to cancel or terminate the contract by either party. Our client services agreements provide for immediate termination upon any default of the client regardless of when notice is given. We report professional employer services revenues on a net basis because we are not the primary obligor for the services provided by our co-employed clients to their customers pursuant to our client services agreements. Consequently, our professional employer service revenues represent the gross margin generated from our professional employer services after deducting the amounts invoiced to clients for direct payroll expenses such as salaries and wages and safety incentives. These amounts are also excluded from cost of revenues. Professional employer service revenues also include amounts invoiced to our clients for employer payroll-related taxes and workers’ compensation coverage. Staffing services are engaged by customers to meet short-term and long-term personnel needs.

Marketable securities

As of March 31, 2014, the Company’s marketable securities consisted of tax-exempt municipal securities, U.S. Treasuries, variable rate demand notes (VRDN) and corporate bonds. The Company classifies municipal securities, U.S. Treasuries, VRDN and corporate bonds as available for sale; they are reported at fair value with unrealized gains and losses, net of taxes, shown as a component of accumulated other comprehensive income (loss) in stockholders’ equity. In the event a loss is determined to be other-than-temporary, the loss will be recognized in the statement of operations.

- 8 -

Table of Contents

BARRETT BUSINESS SERVICES, INC.

Notes to Consolidated Financial Statements (Unaudited) (Continued)

Note 1 - Basis of Presentation of Interim Period Statements (Continued)

Allowance for doubtful accounts

The Company had an allowance for doubtful accounts of $264,000 and $242,000 at March 31, 2014 and December 31, 2013, respectively. The Company must make estimates of the collectability of accounts receivable. Management analyzes historical bad debts, customer concentrations, customer creditworthiness, current economic conditions and changes in customers’ payment trends when evaluating the adequacy of the allowance for doubtful accounts. The Company deems an account balance uncollectible only after it has pursued all available assets of the customer and, where applicable, the assets of the personal guarantor.

Workers’ compensation claims

The Company is a self-insured employer with respect to workers’ compensation coverage for all of its employees (including employees co-employed through our client service agreements) working in California, Oregon, Maryland, Delaware and Colorado, except as described below. In the state of Washington, state law allows only the Company’s staffing services and internal management employees to be covered under the Company’s self-insured workers’ compensation program. Additionally, the Company operates a wholly-owned fully licensed insurance company, Ecole Insurance Company (“Ecole”), in Arizona to provide workers’ compensation coverage to our employees in Arizona.

To manage our financial exposure, in the event of catastrophic injuries or fatalities, the Company maintains excess workers’ compensation insurance through our wholly owned captive insurance company, Associated Insurance Company for Excess (“AICE”), with a per occurrence retention of $5.0 million, except in Maryland and Colorado, where our per occurrence retention is $1.0 million and $2.0 million, respectively. AICE maintains excess workers’ compensation insurance coverage with ACE Group (“ACE”), between $5.0 million and $15.0 million per occurrence, except in Maryland, where coverage with ACE is between $1.0 million and $25.0 million per occurrence, and in Colorado, where the coverage with ACE is between $2.0 million and statutory limits per occurrence. The Company continues to evaluate the financial capacity of its insurers to assess the recoverability of the related insurer receivables.

The Company has provided a total of $120.1 million and $112.4 million at March 31, 2014 and December 31, 2013, respectively, as an estimated future liability for unsettled workers’ compensation claims liabilities. The estimated liability for unsettled workers’ compensation claims represents management’s best estimate, which includes an evaluation of information provided by the Company’s internal claims adjusters and our third-party administrators for workers’ compensation claims coupled with management’s evaluations of historical claims development and other trends. Included in the claims liabilities are case reserve estimates for reported losses, plus additional amounts based on projections for incurred but not reported claims and anticipated increases in case reserve estimates. Also included in these estimates are amounts for unallocated loss adjustment expenses, including legal costs. These estimates are continually reviewed and adjustments to liabilities are reflected in current operating results as they become known.

- 9 -

Table of Contents

BARRETT BUSINESS SERVICES, INC.

Notes to Consolidated Financial Statements (Unaudited) (Continued)

Note 1 - Basis of Presentation of Interim Period Statements (Continued)

Workers’ compensation claims (Continued)

In February, 2014, the Company entered into a workers’ compensation insurance arrangement with ACE to provide coverage to BBSI employees in California beginning in the first quarter of 2014. The agreement will be effective through January 2015 with the potential for annual renewals thereafter.

The arrangement, typically known as a fronted program, provides BBSI a licensed, admitted insurance carrier in California to issue policies on behalf of BBSI without the intention of transferring any of the worker’s compensation risk for the first $5.0 million per claim. The risk of loss up to the first $5.0 million per claim is retained by BBSI through an indemnity agreement. While this portion of the risk of loss remains with BBSI, ACE assumes credit risk should BBSI be unable to satisfy its indemnification obligations to ACE. ACE also bears the economic burden for all costs in excess of $5.0 million per claim. The arrangement with ACE addresses the requirements of legislation enacted in California in 2012 (Senate Bill 863) under which the Company cannot continue its self-insurance program in California beyond January 1, 2015.

During the first quarter of 2014, the Company made an initial deposit of $20.0 million into a trust account established between the Company and ACE related to the new ACE fronted insurance program. The Company will begin making monthly payments in April 2014 into the trust account comprised of premium costs to be set aside for payment of future claims.

Safety incentives liability

Safety incentives represent cash incentives paid to certain client companies under client service agreements for maintaining safe-work practices in order to minimize workplace injuries, thereby meeting agreed-upon loss objectives. The Company has provided $12.2 million at March 31, 2014 and $13.1 million at December 31, 2013 as an estimate of the liability for unpaid safety incentives. The incentive is based on a percentage of annual payroll and is paid annually to customers who meet predetermined workers’ compensation claims cost objectives. Safety incentive payments are made only after closure of all workers’ compensation claims incurred during the customer’s contract period. The liability is estimated and accrued each month based upon the incentive earned less the then-current amount of the customer’s estimated workers’ compensation claims reserves as established by the Company’s internal and third-party claims administrators, and the expected payout as determined by historical incentive payment trends. Safety incentive expense is netted against professional employer services revenue in our consolidated statements of operations.

Statements of cash flows

Interest paid during the three months ended March 31, 2014 and 2013 did not materially differ from interest expense. Income taxes paid by the Company during the three months ended March 31, 2014 and 2013 totaled $1.2 million and $5.9 million, respectively.

- 10 -

Table of Contents

BARRETT BUSINESS SERVICES, INC.

Notes to Consolidated Financial Statements (Unaudited) (Continued)

Note 1 - Basis of Presentation of Interim Period Statements (Continued)

Reclassifications

Certain prior year amounts have been reclassified to conform with the 2014 presentation. Such reclassifications had no impact on the Company’s financial condition, operating results, cash flows, working capital or stockholders’ equity.

Note 2 - Revolving Credit Facility

The Company maintains a credit agreement (the “Agreement”) with its principal bank, Wells Fargo Bank, National Association (the “Bank”). The Agreement, which expires October 1, 2017, provides for a revolving credit facility with a current borrowing capacity of up to $19.0 million. The Company had no outstanding borrowings on its revolving credit facility at March 31, 2014 or at December 31, 2013. The Agreement also provides for the continuance of existing standby letters of credit in connection with various surety deposit requirements for workers’ compensation purposes, as to which the amount outstanding totaled approximately $19.4 million at March 31, 2014.

Advances under the revolving credit facility bear interest, at the Company’s option, at either (a) a fixed rate for a term selected by the Company from time-to-time or (b) a fluctuating rate. In each case, the rate is calculated based on LIBOR plus 1.75%. The Agreement also provides for an unused commitment fee of 0.25% per annum on the average daily unused amount of the revolving credit facility.

The credit facility is collateralized by the Company’s accounts receivable and other rights to receive payment, general intangibles and equipment. Under the Agreement, the maximum principal amount available is reduced by $2.5 million every six months commencing April 1, 2013.

The Agreement, as amended, requires the satisfaction of certain financial covenants as follows:

- 11 -

Table of Contents

BARRETT BUSINESS SERVICES, INC.

Notes to Consolidated Financial Statements (Unaudited) (Continued)

Note 2 - Revolving Credit Facility (Continued)

The Agreement also contains customary events of default. If an event of default under the Agreement occurs and is continuing, the Bank may declare any outstanding obligations under the Agreement to be immediately due and payable. The Company was in compliance with all applicable financial covenants at March 31, 2014.

Note 3 - Basic and Diluted Earnings Per Share

Basic earnings per share are computed based on the weighted average number of common shares outstanding during the period. Diluted earnings per common share reflect the potential effects of the exercise of outstanding stock options and vesting of restricted stock units. Basic and diluted common shares outstanding are summarized as follows (in thousands):

As a result of the net loss reported for the three months ended March 31, 2014 and 2013, 298 and 291 potential common shares, respectively, have been excluded from the calculation of diluted loss per common share because their effect would be anti-dilutive.

- 12 -

Table of Contents

BARRETT BUSINESS SERVICES, INC.

Notes to Consolidated Financial Statements (Unaudited) (Continued)

Note 4 - Workers’ Compensation

The following table summarizes the aggregate workers’ compensation reserve activity (in thousands):

- 13 -

Table of Contents

BARRETT BUSINESS SERVICES, INC.

Notes to Consolidated Financial Statements (Unaudited) (Continued)

Note 5 - Fair Value Measurement

Marketable securities consist of the following investments (in thousands):

The Company’s long-term restricted marketable securities component of restricted marketable securities and workers’ compensation deposits consists of the following (in thousands):

The Company’s long-term restricted certificates of deposit are summarized as follows (in thousands):

- 14 -

Table of Contents

Overview

Barrett Business Services, Inc. (“BBSI,” the “Company,” “our” or “we”), is a leading provider of business management solutions for small-and mid-sized companies. The Company has developed a management platform that integrates tools from the human resource outsourcing industry and a knowledge-based approach from the management consulting industry. This platform, through the effective leveraging of human capital, assists our business owner clients in more effectively running their business. We believe this platform, delivered through local teams of professionals, differentiates BBSI from our competitors. BBSI was incorporated in Maryland in 1965.

Business Strategy.

Our strategy is to align with the mission of small-and mid-sized business owners, driving value to their business. To do so, BBSI:

Business Organization.

We operate a decentralized delivery model using locally based teams, typically located within 50 miles of our client companies. We recruit senior level managers to oversee, develop and expand our business at the branch-office level. Additionally, we recruit professionals with expertise in human resources, risk management and workplace safety and various types of administration, including payroll, to field our client delivery teams. This structure fosters autonomous decision-making, allowing local teams of professionals to deliver plans that most closely align with the needs of each business owner client. It also assists us by incubating talent to support increased growth and capacity. We have clients with employees located in 22 states and the District of Columbia, through a network of 52 branch locations in California, Oregon, Washington, Idaho, Arizona, Nevada, Utah, Colorado, Maryland, Delaware and North Carolina. We also have several smaller recruiting locations in our general market areas, which are under the direction of a branch office.

BBSI believes that making significant investments in the best talent available allows us to leverage the value of this investment many times over. We motivate our management employees through a compensation package that includes a competitive base salary and the opportunity for profit sharing. At the branch level, profit sharing is in direct correlation to client performance, reinforcing a culture focused on achievement of client goals.

- 15 -

Table of Contents

Our Services

BBSI’s core purpose is to advocate for business owners, particularly in the small-and mid-sized business segment. Our evolution from an entrepreneurially run company to a professionally managed organization has helped to form our view that all businesses experience inflection points at key stages of growth. The insights gained through our own growth, along with the trends we see in working with more than 3,000 companies each day, define our approach to guiding business owners through the challenges associated with being an employer.

BBSI’s business teams align with each business owner client through a structured three-tiered progression. In doing so, business teams focus on the objectives of each business owner and deliver planning, guidance and resources in support of those objectives.

Tier 1: Tactical Alignment

The first stage focuses on the mutual setting of expectations and is essential to a successful client relationship. It begins with a process of assessment and alignment in which the business owners’ attitudes, objectives and culture are aligned with BBSI’s processes, controls and culture. This stage includes an implementation process, which addresses the administrative components of managing employees.

Tier 2: Dynamic Relationship

The second stage of the relationship focuses on the development of the client’s organization. There is a focus on process improvement, development of best practices, supervisor development and leadership training.

Tier 3: Strategic Counsel

With a focus on advocating for the business owner, activities in the third stage of the relationship are more strategic and forward-looking with a goal of cultivating an environment in which all efforts are directed by the mission and objectives of the business owner.

In addition to serving as resource and guide, BBSI has the ability to provide workers’ compensation coverage as a means of meeting statutory requirements and protecting our clients from employment-related injury claims. Through our internal claims managers and our third-party administrators, we provide claims management services for our co-employed clients. We work aggressively to manage and reduce job injury claims, identify fraudulent claims and structure optimal work programs, including modified duty employees.

Results of Operations

The following table sets forth percentages of total revenues represented by selected items in the Company’s Consolidated Statements of Operations for the three months ended March 31, 2014 and 2013.

- 16 -

Table of Contents

Results of Operations (Continued)

We report professional employer services revenues on a net basis because we are not the primary obligor for the services provided by our co-employed clients to their customers pursuant to our client service agreements. The presentation of revenues on a net basis and the relative contributions of staffing and professional employer services revenues can create volatility in our gross margin percentage. The general impact of fluctuations in our revenue mix is described below.

- 17 -

Table of Contents

Results of Operations (Continued)

We present for comparison purposes the gross revenues and cost of revenues information set forth in the table below. Although not in accordance with GAAP, management believes this information is more informative as to the level of our business activity and more illustrative of how we manage our operations, including the preparation of our internal operating forecasts, because it presents our professional employer services on a basis comparable to our staffing services.

- 18 -

Table of Contents

Results of Operations (Continued)

A reconciliation of non-GAAP gross professional employer services revenues to net professional employer services revenues is as follows: