Washington sales tax on invoices (2026 guide)

Washington's state sales tax rate is 6.5%, and cities and counties add local sales tax on top. For the fourth quarter of 2026 (October 1 – December 31), combined rates on the Department of Revenue's list run from 7.6% to 10.7%, and Seattle is 10.55%.

Washington also changed the rules for service businesses. Since October 1, 2025, a long list of services that used to be tax-free (including advertising, IT services, custom websites and custom software) is subject to retail sales tax. If you're a freelancer or agency billing Washington clients, read this guide before you send your next invoice.

Washington sales tax rates

Washington is destination-based: the Department says retailers must collect sales tax at the rate for where the customer receives the goods or services. Local rates change quarterly, so check the Department's current rate table or its address lookup each quarter rather than reusing an old rate.

Once you know the combined rate, our sales tax calculator works out the tax and the total for you.

Which services are taxable in Washington?

Washington taxes retail sales of most goods and digital products, plus a set of services. ESSB 5814 added seven categories of services, effective October 1, 2025:

• Advertising services: ad design, ad placement, campaign planning, lead generation, search engine marketing and buying advertising space online. Some things are excluded, such as web hosting, domain name registration, newspaper and print advertising, radio and TV broadcasting, and out-of-home advertising like billboards.
• Information technology services: help desk, network support, IT training, IT consulting, data processing and data entry.
• Custom website development: website design, development and support.
• Live presentations: workshops, webinars and courses with real-time interaction, in person or online.
• Investigation, security and armored car services, including security guards, background checks and security systems.
• Temporary staffing: supplying workers to businesses under contract or on short-term assignment.
• Custom software and customization of prewritten software.

Changes made in 2026

The Legislature adjusted these rules in its 2026 session:

• From July 1, 2026, some activities no longer count as taxable live presentations (for example, certain presentations by nonprofits), schools and libraries get a new exemption for buying certain of these services, and temporary staff provided at hospitals are excluded from temporary staffing.
• ESSB 6346 repeals the sales tax on the ESSB 5814 services except advertising services, effective January 1, 2029. Until then, these services remain taxable, and advertising services stay taxable after that date.

The Department is also running a temporary penalty relief program for businesses that didn't collect tax on these services between October 1, 2025 and December 31, 2026. It waives penalties, not the tax or interest, and applications are due by September 30, 2027.

Registering to collect Washington sales tax

You collect Washington sales tax through your Washington business account and report it, along with B&O tax, on the excise tax return.

If you're based outside Washington, the Department says you must register once you have more than $100,000 in combined gross receipts sourced or attributed to Washington in the current or prior calendar year. Exempt sales count toward that total. Once you pass it, you collect and report for the rest of that year and the following calendar year.

Sales tax vs. B&O tax

Washington also has a business and occupation (B&O) tax. It's easy to confuse with sales tax, but it works differently:

• The Department says the B&O tax is not collected from customers; the business pays it.
• It's calculated on gross income, with no deduction for labor, materials or other costs.

So the B&O tax is a cost of doing business. Don't add it to your invoice as a tax line.

What a Washington sales tax invoice should show

• your business name and address,
• the customer's name and address,
• a unique invoice number and invoice date,
• a description and price for each item or service,
• retail sales tax stated separately from the selling price, with the rate you used, and
• the total due.

Washington law requires the sales tax to be stated separately on the invoice or other sales document. If it isn't itemized, the Department may treat the tax as unpaid. Put taxable and non-taxable work on separate lines; in Invoice Native, tick Tax only on the taxable lines.

Reseller permits and exemptions

When a business buys something to resell, the Department says it must give you a reseller permit. If it doesn't, you charge retail sales tax on the full purchase. A few points:

• Reseller permits are generally valid for four years (two years in some cases, such as for contractors).
• You can verify a permit with the Department's free reseller permit verification tool.
• Keep your documentation for wholesale sales for five years. You have up to 120 days after the sale to get it.

Other exempt buyers use approved exemption certificates. See how to invoice a tax-exempt customer.

A worked example

Say you're a web developer and you build a custom website for a client in Seattle, where the Q4 2026 combined rate is 10.55%. Custom website development has been taxable since October 1, 2025.

For a $4,000 project, the tax is $4,000 × 10.55% = $422.00, and the invoice total is $4,422.00. The sales tax goes on its own line. Your B&O tax on the $4,000 is your own cost and doesn't appear on the invoice.

Selling to customers in other states

If you ship goods or deliver taxable services to customers in another state, that state's rules may apply instead of Washington's. Since the Supreme Court's 2018 decision in South Dakota v. Wayfair, states can require out-of-state sellers to register and collect their sales tax once sales into the state pass a threshold the state sets. If you sell across state lines regularly, check the thresholds and registration rules of each state you sell into, and use that state's rate on those invoices.

Common mistakes on Washington invoices

• Assuming your services are still tax-free. Advertising, IT, custom website and custom software work became taxable on October 1, 2025.
• Using your own city's rate instead of the rate where the customer receives the service.
• Reusing last quarter's rate. Local rates change quarterly.
• Adding B&O tax to the invoice. It's the seller's tax, not the customer's.
• Leaving sales tax out of the invoice or folding it into the price. It must be stated separately.

Quick checklist for Washington invoices

• ✅ Checked whether your services are on the ESSB 5814 list
• ✅ Destination rate for the current quarter (Seattle 10.55% in Q4 2026)
• ✅ Sales tax stated separately on every invoice
• ✅ No B&O tax line on the invoice
• ✅ Reseller permits verified and kept for five years