Washington Sales Tax for Ecommerce Sellers (2026 Guide)

Washington sales tax starts at 6.5% and climbs past 10% in much of the Seattle metro once local rates stack on. Remote sellers owe collection once they pass $100,000 in gross Washington sales. And then comes the part almost every out-of-state seller misses: Washington also charges a business and occupation (B&O) tax on your gross receipts, and it's your bill even when Amazon collected every cent of the sales tax. Sellers who learn about B&O from a Department of Revenue letter are the rule, not the exception. Let's make sure you're not one of them.

The rates: 6.5% state, up to 10.6% combined

The state rate is 6.5%. Cities, counties and transit districts add local rates on top, producing combined rates from about 7.5% in rural areas to 10.35% in Seattle and 10.6% in a few King and Snohomish County cities, among the highest in the country. There is no Washington equivalent of Florida's surtax cap; the full combined rate applies to the whole price.

Washington is strictly destination-based for interstate sellers: you charge the rate where the customer takes delivery, down to the specific address, because rates change at city and district lines. The state's Tax Rate Lookup tool (and its free GIS API) resolves any address to the right rate and location code. That location code matters later: your return reports collected tax by code so the state can route the local share, which is why Washington returns are genuinely tedious by hand and why an automated tax engine earns its fee here faster than in most states.

Shipping is taxable here

Unlike states with carve-outs for separately stated freight, Washington taxes delivery charges whenever the sale itself is taxable. The $5.99 shipping line on a taxable order into Tacoma gets taxed at Tacoma's full combined rate, separately stated or not. If your cart's Washington settings exempt shipping, you're under-collecting on every order, and the shortfall is yours to absorb. Sales for resale and other exempt sales carry their shipping exemption with them, so wholesale freight stays untaxed.

Economic nexus: $100,000, measured on gross

You establish economic nexus once your cumulative gross receipts into Washington exceed $100,000 in the current or prior calendar year. Note the word gross: unlike Florida, which counts only taxable sales, Washington counts everything, including marketplace sales, wholesale sales and exempt sales. Amazon doing $90,000 of your Washington volume plus $15,000 through your Shopify store puts you over the line even though your direct channel alone never would.

Washington dropped its old 200-transaction test back in 2019, so dollars are the only trigger. Crossing the threshold obligates you to register, collect sales tax on your direct retail sales, and, this is the trap, pay B&O on the whole gross.

The B&O tax: the bill nobody expects

Washington has no corporate or personal income tax. Instead it taxes gross receipts through the B&O tax. Not profit. Gross. There are no deductions for inventory cost, ad spend, marketplace fees or anything else, which makes it a fundamentally different animal from income tax: you can lose money and still owe it.

The classifications that matter to sellers:

Classification	Rate	Applies to
Retailing	0.471%	Sales to consumers, including your marketplace and direct-channel retail sales
Wholesaling	0.484%	Sales for resale, with a reseller permit on file
Service & other activities	1.5% and up	Services; 2025 legislation pushed rates higher for larger service businesses

Run the numbers and B&O is small per dollar: $500,000 of Washington retail sales owes about $2,355 under retailing. What makes it dangerous is that nobody budgets for it, it applies to marketplace sales you thought were "handled," and unfiled periods pile up penalties (up to 29% of the tax) plus interest until the total stops being small. We've seen sellers open a DOR letter covering four years of unreported marketplace gross; none of the individual years hurt, the stack did.

The relief valve: Washington's small business B&O credit phases out the tax for low gross volumes, roughly the first $7,000-and-change per month of retailing gross for a monthly filer. Below that, the return still gets filed but the B&O line nets to zero. Above it, you pay. Either way, the obligation to file exists, and "I owed nothing so I didn't file" is not a position the DOR accepts.

Marketplace sales: Amazon collects the sales tax, you still owe the B&O

Washington was the first state in the country to force marketplace collection: Amazon has been collecting Washington sales tax on marketplace orders since January 1, 2018, and every major platform followed. So the sales tax on your FBA, Walmart, eBay, Etsy and TikTok Shop orders into Washington genuinely is collected and remitted by the platform.

Here's how it actually flows on your combined excise return, because this is where sellers file wrong:

• Retailing B&O: report your full Washington gross, including marketplace sales. This tax is yours; no facilitator pays it for you.
• Retail sales tax: report the same gross, then take the deduction for "retail sales tax collected by facilitator" so you're not remitting tax the platform already remitted. Your direct-channel sales get no such deduction; you collect and remit those yourself.

Getting this right requires knowing your Washington gross by channel, which is a bookkeeping question before it's a tax question. Books that post settlement-level detail (the fix for the deposit-as-revenue problem) produce state-by-state gross from a report. Books built on bank deposits can't, and reconstructing Washington gross from two years of settlement CSVs at letter time is exactly as fun as it sounds. The same discipline is what keeps your federal numbers tied to the 1099-K, so it pays for itself twice.

FBA inventory in Washington

Amazon's home state is dense with fulfillment centers (Kent, Sumner, DuPont, Spokane and more), and inventory in any of them is physical presence, with no dollar threshold attached. The practical consequence mirrors the economic-nexus one: register, pay B&O on your Washington gross, and collect on direct sales from dollar one. If FBA has been placing your inventory in Washington for years and you've never registered, don't just quietly start filing; Washington runs a voluntary disclosure program that limits lookback to four years and waives the 29% penalty, and it's the better door to walk through. That's a conversation for our tax services team before it's a form.

Registering, including without an SSN

Registration is a Business License Application with the Department of Revenue (about $90, one time), which issues your UBI number and opens your excise tax account. You'll declare your estimated volume, and the DOR assigns a filing frequency from it.

International sellers can register: the application accepts an EIN in place of an SSN, and a foreign entity without any US tax ID should get the EIN first via the fax-and-phone route in our tax ID guide. Expect the process to take a few weeks end to end. If you're a foreign-owned LLC, keep the federal side in view too; Washington registrations have a way of surfacing during the diligence our international sellers page describes, usually right next to a missed Form 5472.

Physical presence works the old-fashioned ways too, not just through FBA racks. An employee working from a Spokane home office, a rep who visits Washington retail buyers, inventory at a Kent 3PL, even regular trade-show selling in Seattle can each establish nexus on their own, threshold or no threshold. Remote teams make this one sneaky: plenty of sellers acquired Washington nexus the day a customer-service hire moved to Vancouver, and found out two years later. Keep a simple state-by-state list of where your people, inventory and property sit, and revisit it when anything moves.

Registered businesses also get a reseller permit, Washington's version of a resale certificate, so you can buy inventory tax-free for resale. Unlike most states, the DOR issues it (you apply, they can decline), and it renews on a two-or-four-year cycle. Use tax applies when you pull inventory for personal use or promo giveaways, same as everywhere.

Filing: the combined excise tax return

Washington bundles sales tax and B&O into one combined excise tax return, filed through MyDOR. Frequencies and due dates:

Frequency	Due date
Monthly	25th of the following month
Quarterly	Last day of the month after the quarter ends
Annual	April 15

The DOR assigns your frequency based on estimated tax and adjusts it as your volume changes. Returns are due even for zero-activity periods once the account is open; skipping "nothing happened" periods is the most common way small sellers rack up late-filing penalties on tax they never owed. E-filing is required, and the return wants that by-location-code breakdown of collected tax, which your tax engine or settlement-level books should be producing for you.

One more small levy for completeness: Washington's litter tax (0.015%) applies to sellers of certain product categories like food, beverages and toiletries. It's pocket change, it lives on the same return, and knowing it exists is most of the work.

Keep your support records five years: settlement reports, the by-state sales detail behind each return, reseller permits from wholesale customers, and the location-code breakdowns. Washington's standard audit window is four years plus the current year, and DOR audits are famously data-driven; they'll ask for your marketplace reports and run the math themselves. An audit where your filed numbers regenerate from your books in an afternoon ends quickly. The other kind doesn't.

A worked example: what a typical seller actually owes

Say you're a Texas-based brand doing $900,000 a year nationally: $70,000 of Washington marketplace sales through Amazon and $15,000 direct through Shopify, so $85,000 of Washington gross this year, but $102,000 last year. Last year's number put you over the threshold, so you're in the system. Here's the annual damage:

• Sales tax on marketplace orders: $0 out of pocket. Amazon collected and remitted it.
• Sales tax on the $15,000 of Shopify orders: collected from customers at each delivery address, roughly $1,400 at typical combined rates, remitted on your returns. Cost to you if you collected properly: nothing. Cost if your cart wasn't set up: the full $1,400 out of margin.
• Retailing B&O on $85,000 gross: about $400 before the small business credit, likely less after it.
• The filing itself: four quarterly combined excise returns, maybe an hour each with clean books.

Total real cost: a few hundred dollars and a few hours, if handled on time. The same facts discovered by the DOR after three silent years: back B&O, uncollected direct-channel sales tax you now eat yourself, penalties near 29%, and interest. Washington compliance is cheap; Washington non-compliance compounds.

Washington sales tax FAQ

What is the sales tax rate in Seattle? 10.35% combined as of 2026: the 6.5% state rate plus Seattle-area local rates. A few nearby cities run 10.6%.

Are digital products taxable in Washington? Yes, broadly. Washington taxes digital products, streamed and downloaded goods, and much of what other states leave alone, and its 2025 legislation extended retail sales tax deeper into services (advertising, IT and others). Digital and hybrid sellers should assume taxable until proven otherwise, the reverse of Florida's posture.

Is the B&O tax deductible on my federal return? Yes. State gross-receipts taxes are an ordinary business expense, deductible like any other. It softens the sting a little; it doesn't excuse not filing.

I sell only through Amazon. Do I really owe Washington anything? If you're over the $100,000 gross threshold or have FBA inventory in the state: yes, retailing B&O on your Washington marketplace gross, filed on the combined excise return, even though Amazon remitted all the sales tax. This is the single most common Washington surprise for out-of-state sellers.

Are groceries taxable in Washington? Most food and food ingredients are exempt, but prepared foods, soft drinks and dietary supplements are taxable. Supplement sellers take note: your product is taxable here even though it feels like "food."

Washington vs Florida: a tale of two audits

Put this guide next to our Florida guide and the contrast is instructive. Florida measures only your direct taxable sales, ignores marketplace volume for your threshold, and even pays you a small allowance for filing on time. Washington measures gross everything, keeps a second tax running underneath the one the platforms handle, and wants the paperwork regardless of whether money is due. Neither is hard once your books produce channel-level, state-level gross on demand. Both are miserable without that, which is the actual lesson: multistate sales tax is a reporting problem wearing a tax costume.

Getting it handled

If you're past $100K into Washington, the to-do list is short: register, set your direct channels to collect at destination rates, report marketplace gross under retailing B&O with the facilitator deduction, and file on your assigned cycle. If there are unfiled years behind you, voluntary disclosure first. And if your books can't tell you your Washington gross by channel in five minutes, that's the root problem: it's the kind of gap our free Ecommerce Books Teardown catches immediately (request one here), and fixing it is the first week of a proper monthly bookkeeping engagement. State tax filings, including combined excise returns, are part of our ecommerce tax services; the books and the returns are one job done right, not two done separately.