States
Wisconsin and the Streamlined Sales Tax program
Simplify Sales Tax. Last updated 2026-08-21. Sources last verified 2026-08-21.
Wisconsin is a full member of the Streamlined Sales Tax program and has been since October 1, 2009, so if you register through the Streamlined Sales Tax Registration System (SSTRS) you file there under the program’s uniform rules. The local layer here is county tax where a county has adopted it plus a city of Milwaukee sales tax on sales delivered into the city, so a setup that only knows about county tax won’t charge enough on a Milwaukee order.
Is Wisconsin in the Streamlined Sales Tax program?
Yes, as a full member, effective October 1, 2009. Wisconsin is one of all 24 member states in the Streamlined Sales Tax program.
Table: Wisconsin in the Streamlined Sales Tax program. Checked August 21, 2026.
| Item | Wisconsin |
|---|---|
| Membership status | Full member |
| Participating since | October 1, 2009 |
| Tax authority | Wisconsin Department of Revenue, which administers the county sales and use tax as well as the state tax |
| Local taxes | County sales and use taxes apply in the counties that have adopted the tax, and a city of Milwaukee sales tax applies to taxable retail sales delivered to locations in the city, both collected by a retailer holding a Wisconsin seller’s permit |
| State’s own SST page | None published |
| Remote seller separate transaction count test | Wisconsin eliminated its separate transaction count test for remote seller economic nexus effective February 20, 2021 |
| Exemption certificates | Wisconsin provides an electronic exemption certificate for exempt purchases |
What SST membership changes for a seller collecting tax in Wisconsin
Wisconsin comes with the other member states when you register once, on how to register through the SSTRS. It uses the program’s shared definitions and sourcing rules, so one system files there. Selecting it starts an obligation, on what your ongoing obligations are after registering, and whether you qualify to have that work paid for is a separate test, on whether you qualify for free CSP services.
What is specific to Wisconsin
Two things.
County tax reaches only the counties that have adopted it, and the city of Milwaukee has a sales tax of its own. The Wisconsin Department of Revenue administers both with the state tax, so there’s no local filing to add and one place to ask when a local figure looks wrong. Holding a Wisconsin seller’s permit is what obliges you to collect the county tax in an adopting county and the city tax on taxable retail sales delivered into Milwaukee, and which counties have adopted the tax is on the department’s own list. A system configured for county alone doesn’t charge enough on a Milwaukee order, and a county’s decision to adopt arrives as a rate change rather than new paperwork.
Wisconsin’s separate transaction count test is gone. Wisconsin eliminated the separate transaction count test effective February 20, 2021. So if anything internal still counts your Wisconsin transactions, a spreadsheet or a rule in your billing system, it’s watching a test the state no longer applies, and that’s worth an hour of somebody’s time to find and switch off. Read your Wisconsin notes against that date too: a memo written before February 20, 2021 describes the test as it stood then.
None of that goes away because Wisconsin is a member state. From October 1, 2009 the program reached the definitions Wisconsin taxes against and the registration that puts you on its rolls, and it left the local layer where it was, with the counties that adopt the tax, the city of Milwaukee, and the department that collects both. Your Wisconsin filing calendar and the local detail behind it are still yours to track. The exemption certificates still have to be collected and kept, and none of it reaches the states outside the program at all.
Where to register and where to find current rates
Register through the SSTRS and select Wisconsin. The current state, county, and city rates, the forms, the exemption certificate, and the filing dates are on Wisconsin sales and use tax, and which counties have adopted the tax and how the city of Milwaukee tax applies are on its county and city tax questions. Wisconsin publishes no Streamlined page of its own, so the department’s own account of its participation isn’t there to read, and the Governing Board’s Wisconsin page is the published record.
We don’t publish a Wisconsin rate or a filing date here on purpose: a number that changes belongs with the department that changes it.