Form ST-12 at a glance
What it is: Form ST-12 is the Wisconsin Department of Revenue's State, County, and City Sales and Use Tax Return.
Where and when to file: Mail to: Wisconsin Department of Revenue PO Box 8921 Madison WI 53708-8921
A filled-in Form ST-12 example: a store reports one quarter of sales tax
How to fill out Form ST-12, box by box
Tax Account Number, FEIN / SSN and Due Date
In Tax Account Number, enter the 15-digit number (no dashes).
Enter your FEIN / SSN.
Enter the Due Date, Period Begin Date and Period End Date as MM DD YYYY.
Attention, Business Name, Legal Name and Mailing Address
Fill in Attention, Business Name, Legal Name, Mailing Address - Street or PO Box, City, State and Zip Code.
Check if boxes at the top of the form
Check if business discontinued, and enter the discontinuation date (MM DD YYYY).
Check if address or name change, and note changes at left.
Check if this is an amended return.
Check if correspondence is included.
Sales Tax - State
On line 1, enter Total sales. Under Subtractions from total sales, line 2 is Sales for which you received exemption certificates, and line 3 is Sales of exempt property and services (sales that occurred outside Wisconsin, real property, groceries and highway fuel, etc. ).
On line 4, enter Sales returns, allowances, and bad debts.
On line 5, enter Other (sales tax included in line 1, etc. ).
On line 6, enter Total subtractions (add lines 2 through 5).
On line 7, enter Sales subject to state sales tax (subtract line 6 from line 1).
On line 8, enter State sales tax (line 7 x . 05).
Sales Tax - County and City
Complete Schedule CT (pages 3 and 4).
Line 9 will autofill from Page 4, Column 1. Enter total from Schedule CT, Col. 1 on line 9a, then 9a x . 005 = 9b.
On line 10, Milwaukee County taxable sales after 2023 10a x . 009 = 10b, and Milwaukee County taxable sales before 2024 10c x . 005 = 10d.
On line 11, City of Milwaukee taxable sales after 2023 11a x . 02 = 11b.
On line 13, enter Total sales tax (add lines 8, 9b, 10b, 10d and 11b).
Retailer's discount and Net sales tax
On line 14, fill in the Total sales tax amount from line 13.
On line 15, enter Retailer's discount (see instructions).
On line 16, enter Net sales tax (subtract line 15 from line 14).
Purchases subject to state use tax
On line 17, Purchases subject to state use tax 17a x . 05 = 17b.
Use Tax - County and City
Complete Schedule CT (pages 3 and 4). Line 18 will autofill from Page 4, Column 2. Enter total from Schedule CT, Col. 2 on line 18a, then 18a x . 005 = 18b.
On line 19, Milwaukee County taxable purchases after 2023 19a x . 009 = 19b, and Milwaukee County taxable purchases before 2024 19c x . 005 = 19d.
On line 20, City of Milwaukee taxable purchases after 2023 20a x . 02 = 20b.
Total Amount Due
On line 22, enter Total sales and use taxes (add lines 16, 17b, 18b, 19b, 19d and 20b).
On line 23, enter Interest.
On line 24, enter Late filing fee ($20.00) and negligence penalty (checked November 1, 2026).
On line 25, enter Total amount due (add lines 22 through 24).
Signature, Contact Person and Mail to
By signing, you certify that this return, including any accompanying schedules and statements, has been examined by you and to the best of your knowledge and belief is a true, correct, and complete return.
Fill in Contact Person (please print clearly) and Phone Number, sign on the Signature line, and fill in Date.
Mail to: Wisconsin Department of Revenue PO Box 8921 Madison WI 53708-8921
More rules for Form ST-12
To ensure this form works properly, save it to your computer before completing the form.
Tab to navigate throughout form.
Use BLACK INK Only.
Sources
[1] Form ST-12 (R. 4-25), State, County, and City Sales and Use Tax Return, Wisconsin Department of Revenue (the Official source link on this page).
