Short answer: Federal deposits and returns, plus filings with three separate Washington agencies — Employment Security, Labor & Industries, and Paid Family and Medical Leave. Washington has no state income tax, so there is no state withholding, which is the one thing that makes it simpler than most states.
On the federal side you are withholding income tax, Social Security and Medicare from each paycheck, matching the Social Security and Medicare portions as the employer, and depositing all of it on a schedule the IRS assigns you. Those deposits are reported quarterly on Form 941, with federal unemployment reported annually on Form 940. At year end, W-2s go to employees and 1099s to qualifying contractors.
On the state side there are three separate relationships, and this is where new employers most often get tripped up, because each has its own account number and its own login.
Employment Security handles unemployment insurance. Your rate is experience-rated, so it moves over time based on your own claim history.
Labor & Industries handles workers’ compensation. Washington runs its own state fund rather than letting you buy private coverage for most classifications, and premiums are calculated on hours worked rather than wages — which means your payroll system has to be tracking hours correctly, not just dollars.
Paid Family and Medical Leave is premium-based and shared between employer and employee, with the employer share depending on business size. Quarterly reports and premium payments go to that program directly.
Because there is no state income tax withholding, employees here see a simpler paycheck than in Idaho or Oregon — worth knowing if you have staff across the border, because those employees do have state withholding and the rules follow where the work is performed.
Rates and thresholds for all three state programs are reset periodically. Confirm current figures for your business rather than working from last year’s numbers.
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