Washington state payroll tax: A guide for contractors

Contractors operating in Washington state must comply with both federal and state payroll tax requirements. While Washington doesn’t impose state income tax, it has its share of complexities, like hours-based workers’ compensation reporting and social insurance programs. 

Contractors also face a wide range of compliance requirements, from employment verification to prevailing wage rates. And these elements impact every employer and employee working in Washington, regardless of their home state or headquarters location. 

This guide explains how Washington payroll taxes apply to construction wages and what additional points affect any companies operating in the state.

Does Washington have income tax? 5 other payroll taxes to consider

Washington doesn’t have a state income tax, and employers don’t calculate employee withholding using Washington state tax brackets. However, all standard federal payroll taxes still apply to construction companies in operating Washington, and construction companies must also manage several state-mandated payroll programs. 

Here are five common Washington employment taxes and programs to consider.

1. State unemployment insurance (SUI)

Employers fund the Washington Employment Security Department (ESD) unemployment insurance program through payroll taxes. 

Each employer receives an experience tax rating based on how many former employees claimed benefits, and this rating determines how much companies owe. New construction employers typically pay 115% of the average tax rate for their industry. Businesses generally stay in the “new” category for about two or three years before receiving an experience-based tax rate.

As of 2026, employers pay unemployment taxes on wages up to Washington state’s taxable wage base of $78,200. This figure changes annually, so check Washington’s Employment Security Department site for more details.

2. Paid Family and Medical Leave (PFML)

The PFML program provides paid time off for serious health conditions and caregiving. For 2026, the total PFML tax rate is 1.13% of gross wages. This rate applies up to the 2026 Social Security cap of $184,500.

The premium is split between employees (71.43%) and employers (28.57%). Companies with fewer than 50 employees don’t have to pay the employer portion, but they have to withhold the employee share through payroll deductions and remit it to the state.

Optionally, small employers can choose to pay the employee share on behalf of employees as a benefit. Smaller construction companies competing for workers can use this as an incentive to attract more candidates.

3. Washington Cares Fund

This long-term care insurance program provides services like nursing care and home modifications. Employers in Washington state withhold 0.58% payroll premium from staff wages. The WA Cares Fund has no wage cap.

4. Workers’ compensation premiums

Washington’s workers’ compensation system operates through the Washington State Department of Labor and Industries (L&I). Employers and employees pay premiums that fund benefits for workers who experience job-related injuries or illnesses.

The L&I determines insurance rates using specific risk classes for different trades, and they express rates as cents per hour worked rather than as a percentage of pay. Workers performing multiple trades may have different risk classifications, which directly affects premium calculation. 

5. Local payroll taxes

Some Washington cities impose local payroll taxes on employers. For example, large contractors performing work within Seattle city limits might pay the Seattle JumpStart Payroll Expense Tax. This applies if the total annual payroll exceeds $9.07 million and at least one employee earns $194,452 or more. Rates range from 0.7–2.5% depending on the payroll bracket.

Washington state payroll considerations for construction companies

Washington construction employers must account for additional payroll compliance requirements that influence wage calculations and reporting. Even though they aren’t taxes, these rules affect payroll processing. 

Here are a few examples:

• Prevailing wage compliance: For public works projects, contractors must pay the prevailing wage determined by the Department of Labor. This includes a base hourly rate plus fringe benefits. The prevailing wage rates depend on the trade classification and geographic location of the project.
• Paid sick leave requirements: WA law requires one hour of paid sick leave for every 40 hours worked. If a covered construction worker exits before they reach 90 days at the company, contractors must pay out accrued but unused sick leave. This applies to both voluntary exits and terminations. To find out whether an employee is classified as covered, reach out to a lawyer.
• Workers’ compensation reporting: L&I requires employers to report hours worked within each risk classification. Construction workers may perform tasks that fall into different classifications across jobsites, so companies must consider activities per person to ensure the correct premiums apply.
• State and local reporting rules: Construction payroll often depends on project location. In Washington state, contractors working on public projects have to submit an Intent to Pay Prevailing Wages and an Affidavit of Wages Paid to L&I. Payroll records must match these filings and reflect the correct trade classifications and hours worked. 

Construction-specific software like Miter can simplify a multi-location process by connecting time tracking with payroll reporting and worker classification. MJ Mechanical relied on Miter to manage payroll complexities during rapid workforce growth across multiple states. Miter helps them save time and maintain audit-ready accuracy in every county they operate in.

How to pay taxes in Washington state as a construction employer

Managing payroll taxes in Washington requires coordination across federal and state systems. Here are the steps:

• Register with the Washington Department of Revenue: Create a state business account, and obtain a Unified Business Identifier number for all state tax filings.
• Register with the Employment Security Department: Set up an account for SUI and PFML through the SecureAccess Washington portal.
• Establish L&I risk classifications: Workers in construction can shift between risk classifications within a single job, since risk class tracking happens at the activity level. This is especially relevant for companies with mixed-trade crews. Contact L&I to determine the correct risk classes for specific trades.
• Track hours by classification: Collect employee hours by jobsite and cost code. It’s easiest to use a platform like Miter Time Tracking that allows you to map cost codes to L&I risk classes and sync hours worked directly to payroll.
• Remit employee-funded deductions: Quarterly, remit withheld portions of PFML, WA Cares, and L&I Medical Aid funds.
• File required reports: Employers must submit quarterly tax and wage reports to the ESD for UI, PFML, and WA Cares. They must also file a separate quarterly report with L&I to disclose worker hours and pay premiums based on risk qualifications. Federally, employers also need to file Form 941 quarterly and Form 940 annually.

Simplify Washington state payroll with Miter.

Washington state payroll is intricate. Even though there’s no traditional state withholding tax on income in Washington, contractors still have a lot to handle. Construction employers juggle federal taxes and workforce programs, and have to factor in location-specific reports and classification-based pay rates.

Miter reduces the administrative burden by connecting hours worked to payroll processing. Contractors can automatically tie hours to classifications and locations, so time data flows into payroll and job costing with accurate project context. Miter Payroll manages pay and tax calculations and regulations across states, factoring in overtime, garnishments, and benefits.

Disclaimer: This article is for informational purposes only and is not intended as tax advice.