Washington's new 9.9% income tax (ESSB 6346) takes effect January 1, 2028. For anyone who works remotely — or who splits time between Washington and another state — the question is immediate: will I owe this tax?
The answer depends on three things: where you're domiciled, where you maintain a home, and where you physically perform your work. Here's how the statute handles each scenario.
(For an overview of ESSB 6346, see Washington's New Income Tax: What Founders, Investors, Athletes, and High Earners Need to Know. For the full tax landscape, see Washington State Taxes.)
How the Statute Defines "Resident"
ESSB 6346's residency definition creates two independent paths to resident status:
Path 1 — Domicile (with a narrow escape hatch). You're a resident if you're domiciled in Washington during the taxable year — unless you satisfy all three conditions of the 30-day safe harbor:
- (A) You maintained no permanent place of abode in Washington during the entire year;
- (B) You maintained a permanent place of abode outside Washington throughout the entire year; and
- (C) You spent 30 or fewer days in aggregate in Washington during the year.
Failing a safe-harbor condition makes that exception unavailable; it does not by itself establish full-year residency. Determine domicile, any qualifying abode, and the resident portion of the year under ESSB 6346 §101(8). Ownership of Washington real estate alone does not answer every residency question.
Path 2 — Physical presence. Even if you're not domiciled in Washington, you become a resident if you maintained a place of abode in Washington and were physically present for more than 183 days during the year (ESSB 6346 §101(8)).
A "day" means any portion of a calendar day. Fly into SeaTac at 11:55 PM — that's a day. (See The 30-Day Rule for Washington Income Tax Residency (and Why It's Confusing) for a deeper look at how these tests work in practice.)
Residents: All Income Is Taxed, Regardless of Where You Work
Under the statute, if you're a Washington resident, all of your income must be allocated to this state. It doesn't matter that your employer is headquartered in San Francisco, or that you spend three weeks a year at the company's New York office. If you're a resident, Washington taxes your entire federal AGI (as modified), subject to the $1 million standard deduction.
This is a critical point for remote workers. Washington does not care where your employer is located. If you live in Seattle and work remotely for a California company, Washington considers all of your income to be Washington income.
But What About the Tax You Pay to California?
This is where the credit for taxes paid to other states comes in. Washington gives residents a credit for income taxes paid to another state on income that's also included in your Washington base income. The credit is the lesser of:
- The tax you actually paid to the other state on that income; or
- The Washington tax that would be due on that income.
Section 203 calculates the credit separately for each jurisdiction. It is capped at the smaller of qualifying tax paid and pre-credit Washington tax multiplied by federal AGI taxed in the other jurisdiction divided by total Washington base income, with the fraction capped at one. This formula does not guarantee complete relief from overlapping taxation.
Comparing headline rates is not enough to calculate the combined liability. Apply each state’s tax base, deductions, rates and credit rules. Washington allows no refund or carryover of unused Section 203 credit.
Nonresidents: Only Washington-Source Income
If you're not a Washington resident, you're only taxed on income from sources within Washington. For wage earners, "sources within Washington" means compensation from employment performed in the state — regardless of where the employer is located.
The Physical Presence Rule
The statute is explicit: wages from a nonresident's employment are allocated to Washington to the extent services are rendered within the state. If services are performed both within and outside Washington, the compensation is apportioned based on the ratio of days worked in Washington to total days worked, or by another reasonable method approved by the Department of Revenue.
This is a physical presence test. Washington did not adopt a "convenience of the employer" rule like New York, which taxes nonresidents on income earned for a New York employer even when the employee works from home in another state. Under ESSB 6346, if you live in Oregon and never set foot in Washington, you owe zero — even if your employer is a Seattle company.
The Five-Day Safe Harbor
The statute provides a practical safe harbor: if a nonresident individual performs services in Washington for five or fewer days cumulatively in any calendar year, no income from those services needs to be allocated to Washington.
This is a meaningful provision for cross-border workers. If you're an Oregon resident who visits the Seattle office a few times a year for meetings, you're protected — as long as you stay at or under five days.
But be careful. This safe harbor does not apply to professional athletes, student athletes, or nonresident entertainers. And "day" still means any portion of a calendar day.
The Scenarios Remote Workers Actually Face
Scenario 1: Washington Resident, Out-of-State Employer
You live in Seattle. You work remotely for a company based in Austin, Texas.
You're a Washington resident. All of your income is allocated to Washington as a resident. Texas has no income tax, so there's no credit to claim. Result: if your income exceeds the $1 million standard deduction, you owe Washington 9.9% on the excess.
Scenario 2: Washington Resident, Working Partly in Another State
You live in Bellevue. You work for a San Francisco company and fly to the office two weeks per month.
As a Washington resident, include the applicable income in Washington’s resident tax base. If California also taxes work performed there, calculate the available Washington credit under Section 203. The result depends on the actual tax and credit calculations; it is not automatically the higher headline rate on the overlapping income.
Scenario 3: Oregon Resident, Washington Employer
You live in Portland. You work remotely for a Redmond company. You visit the office about once a month.
You're not a Washington resident. Your income is only taxable in Washington to the extent you perform services here. If you visit 12 days per year, your Washington-source compensation is roughly 12/260 (assuming 260 work days) of your total pay — about 4.6%.
Here's the part that surprises people: you do not get the full $1 million deduction against that slice. For nonresidents, the standard deduction is prorated — the same ratio mechanism that applies to part-year residents (Washington base income over total federal AGI). Above five Washington service days, calculate Washington-source income, the prorated standard deduction, and other applicable exclusions, deductions and credits; tax is not automatic. Assuming Washington base income consists solely of Washington-source wages, total income means federal AGI exceeding $1 million, and no other adjustments, deductions or credits apply, the simplified calculation is approximately: 9.9% × Washington-source wages × (1 − $1 million ÷ federal AGI).
Run the numbers. A worker earning $2 million total who spends 12 days a year in the Redmond office has about $92,000 of Washington-source pay and a prorated deduction of about $46,000 — roughly $4,600 of Washington tax. A senior executive earning $5 million who's in the Seattle office 60 days a year has about $1.15 million allocated to Washington, a prorated deduction of about $231,000, and a Washington bill of roughly $91,000. (And you'd owe Oregon tax on everything, with Oregon's credit rules determining the overlap.)
The five-day rule is important for cross-border workers, but it is not the only statutory exclusion. Above five days, calculate allocated income, the prorated deduction and any other applicable relief before concluding that tax is owed.
Scenario 4: Oregon Resident, Occasional Visits Only
You live in Portland. You visit the Seattle office three times a year for planning meetings.
Three days is within the five-day safe harbor. Zero Washington income tax, regardless of your income level.
Scenario 5: You Move Out of Washington Mid-Year
You've been living in Seattle, earning $2 million per year. On July 1, you move to Nevada.
Section 406 controls: you're a part-year resident. Your income is split into the resident portion (all income earned January through June) and the nonresident portion (only Washington-source income earned July through December). If you don't perform any services in Washington after you move, your nonresident portion is zero.
But the $1 million standard deduction is prorated based on the ratio of your Washington base income to your total federal AGI. If your income was evenly distributed, roughly half your total income is Washington base income, so your effective deduction is approximately $500,000. On $1 million of Washington income, you'd owe 9.9% on $500,000 — about $49,500.
Scenario 6: The "Digital Nomad" Who's Still Domiciled Here
You're domiciled in Washington. You travel constantly and work from co-working spaces around the country. You still own a condo in Seattle.
On these facts, if Seattle remains your domicile and the retained home is a permanent place of abode, the 30-day safe harbor is unavailable. Income during your resident period is allocated to Washington, subject to the tax’s modifications, deductions and credits. If domicile changes during the year, analyze the part-year rule separately.
A genuine change of domicile can end the domicile basis for residency; the full-year 30-day safe harbor is a separate route for someone still treated as a Washington domiciliary. After a move, examine the abode-plus-more-than-183-day test and any Washington-source income. See the domicile guide.
What Washington Did Not Do
Several things are notably absent from the statute:
No convenience-of-the-employer rule. New York famously taxes nonresidents on income earned for a New York employer even when the employee works remotely from home in New Jersey. Washington rejected this approach. Under the statute's sourcing rule, nonresident compensation is sourced based on where the services are physically performed, not where the employer is located. This is a significant and deliberate policy choice.
No telecommuting carve-out. Some states have created special rules for pandemic-era remote work arrangements. Washington's statute contains none. The rules are simple: where you physically sit when you do the work is where the income is sourced.
No reciprocal agreements (yet). The statute authorizes the Department of Revenue to enter reciprocal agreements with other states exempting each other's residents from tax on personal service income. As of now, no such agreements exist. Oregon does not currently exempt Washington residents from Oregon income tax on days they work in Oregon, and vice versa. This could change — but don't count on it.
What This Means for Employers
Section 403’s employment definition requires the employer to be subject to RCW 50.24.010 on compensation paid to that individual. Do not assume every independent contractor falls under the employee workday rule. Contractor business income requires separate analysis under the applicable business allocation rules.
Employers with remote workers scattered across state lines will need to track days worked in Washington for employees earning above the threshold. Section 404 also requires entities that pay wages or bonuses to professional athletic team members in Washington to file annual reports — but the broader principle extends conceptually: if you're paying people who sometimes work from Washington, the allocation question is real.
Planning Takeaways
If you're a Washington resident working remotely for an out-of-state company: your income is taxed by Washington. Claim credits for any income tax paid to states where you physically work.
If you live in another state and work for a Washington company: only your days physically present in Washington matter. At five or fewer service days in a calendar year, no income is allocated to Washington. Above five days, calculate the Washington-source income, the prorated standard deduction, and other applicable exclusions, deductions and credits — the deduction is prorated for nonresidents, so there is no full $1 million cushion against Washington-source income alone, but tax is not automatic.
If you are thinking about leaving Washington: distinguish an actual domicile change from the full-year 30-day safe harbor. Retaining a Washington abode matters, but does not automatically make every non-domiciliary a resident. Apply the separate day-count test, part-year rules and income sourcing. See the 30-day rule guide.
If you split time between states: start tracking your days now. The statute takes effect January 1, 2028, but building the habit and documentation practice before then will save you significant headaches. A calendar log showing which state you were in each day, supported by travel records, is the single most important piece of evidence in any residency or sourcing dispute.
Need help assessing how Washington's income tax will apply to your specific work arrangement? Book a 20-minute intro call to discuss your situation. Also see: Washington State Taxes Guide | Income Tax Planning Guide for High Earners
This post is for educational purposes only and is not legal or tax advice. Consult a qualified attorney about your specific situation.
