How to Get a Wisconsin State Tax ID Number: Fees and Renewal

To get a Wisconsin state tax ID number, file a Business Tax Registration with the Wisconsin Department of Revenue, either online through the One Stop Business Portal or by mailing Form BTR-101. The initial fee is $20, and online filers typically receive their 15-digit tax account number within about two business days. That single number tracks sales tax, withholding tax, excise tax, and other obligations tied to your business.¹

Who Needs to Register

Any business making taxable sales or providing taxable services in Wisconsin must obtain a seller’s permit before it begins operating. Wisconsin Statute 77.52(7)(a) requires every person operating as a seller to file a permit application for each place of business.² That covers brick-and-mortar retailers, service providers collecting sales tax, and remote sellers who cross the state’s nexus threshold.

Employers register through the same process. Wisconsin law requires every employer paying wages to employees working in the state to deduct and withhold state income tax from those wages, which means setting up a withholding tax account with the Department of Revenue.³

Businesses dealing in motor fuel, tobacco products, alcohol, or electric vehicle charging need separate excise tax registrations.⁴ Companies that regularly purchase taxable goods without paying sales tax at the time of purchase need a consumer’s use tax certificate.⁵ All of these feed into the same 15-digit tax account number.

Remote Sellers

If your business is located outside Wisconsin but sells to Wisconsin customers, you need a seller’s permit once your gross sales into the state exceed $100,000 in the current or previous calendar year.⁶ Wisconsin measures nexus purely by sales volume, with no separate transaction-count trigger. Once you cross that line, you register through the same Business Tax Registration process as an in-state business.

What to Gather Before You Start

Pull everything together before you open the online application. The system doesn’t let you save a half-finished form and come back later.

A Federal Employer Identification Number, Social Security Number, or ITIN. Sole proprietors without employees can use their Social Security Number; most other entities need a Federal EIN from the IRS.⁷
Your legal business name and any trade names, spelled exactly as they appear on your formation documents or DBA filing.
Your six-digit NAICS code identifying your primary business activity.
The first date you’ll pay employees in Wisconsin and the first date you’ll make taxable sales or purchases. These may not be the same date.⁸
Social Security Numbers or FEINs for every owner, partner, or corporate officer with a significant stake.
Your physical operating address and a reliable mailing address for state correspondence.

During the application, select every tax type that applies: sales and use, employer withholding, excise, or others. Pick only what’s relevant now. You can add tax types later through My Tax Account if your activities change.

Registering Online

The Wisconsin One Stop Business Portal at onestop.wi.gov walks you through registering with multiple state agencies in a single session, including the Department of Revenue, the Department of Financial Institutions, and the Department of Workforce Development.⁹ You’ll need a Wisconsin Access Management System (WAMS) ID to log in, which you can create for free during the process. The portal collects your payment electronically and routes your information to the right agencies.

You can also register directly through the Department of Revenue’s My Tax Account portal at tap.revenue.wi.gov, which handles just the tax registration piece.⁴ That path works well if you’ve already handled your entity formation separately and only need the tax accounts.

Registering by Mail

If you prefer paper, download Form BTR-101 from the Department of Revenue’s website and mail the completed form with your payment to the address printed on the form.⁸ Include a check or money order payable to the Wisconsin Department of Revenue. Paper takes considerably longer to process, so plan accordingly if you have a firm opening date.

Fee, Processing Time, and Receiving Your Permit

The initial registration fee is $20. That fee covers a two-year period and applies to most permit types issued by the Department of Revenue, including seller’s permits, use tax certificates, employer registration certificates, and excise tax permits.¹⁰

Online applications are processed within about two business days. Paper applications take up to 15 business days.⁸ After approval, the department mails a paper permit or certificate within seven to ten business days. State law requires you to display your seller’s permit conspicuously at your place of business. If you operate from a vehicle or a temporary location, carry the permit with you.²

If something in your application doesn’t check out, the department will contact you for clarification before processing further.

Each Location Needs Its Own Permit

Wisconsin requires a separate seller’s permit for each place of business. The statute is explicit: the Department of Revenue issues a separate permit for each place of operations within the state, and each permit is valid only for the location designated on it.² Opening a second retail location or a new warehouse that makes taxable sales means filing another application for that site. The permit is also non-transferable; it’s valid only for the person or entity named on it.

Renewal Every Two Years

Your Business Tax Registration expires after two years. At the end of each two-year period, a $10 renewal fee applies. The Department of Revenue no longer mails a new seller’s permit during the renewal cycle. Instead, you receive a BTR Certificate showing the updated expiration date for your seller’s permit and any other permits or certificates tied to your account.¹⁰ An expired permit carries the same legal consequences as operating without one, so put the expiration date on your calendar.

Penalties for Selling Without a Permit

Selling taxable goods or services in Wisconsin without a valid seller’s permit, or after your permit has been suspended, revoked, or expired, is a misdemeanor. Liability attaches to the business and personally to each corporate officer, partnership member, LLC member, or other person authorized to act on behalf of the seller.² A Department of Revenue representative can order you to stop selling immediately.¹¹

If You’re Buying an Existing Business

Registering as the new owner of an existing Wisconsin business carries a risk that catches buyers off guard. Wisconsin law makes the purchaser of a business or its stock of goods personally liable for the seller’s unpaid sales and use tax if the buyer doesn’t withhold enough of the purchase price to cover those taxes.¹² That liability attaches by operation of law, and no contract between buyer and seller can override it.

The protection is a clearance certificate from the Department of Revenue after the sale closes. Either the buyer or the seller can submit the request, which needs both parties’ names, tax account numbers, the date of sale, and the sale price. The department then has 90 days to either issue the clearance certificate or send a notice of successor liability. If the department doesn’t respond within 90 days, the purchaser is automatically relieved of any liability.¹² A successor’s liability is capped at amounts the prior owner owed at the purchased location, and no penalties or interest are added to what the successor owes.

1
Wisconsin Department of Revenue. Additional Detail Information of WT-6 Batch Payment Schema
2
Wisconsin State Legislature. Wisconsin Code 77.52 – Imposition of Retail Sales Tax
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Wisconsin State Legislature. Wisconsin Code 71.64 – Withholding Income Tax From Wages
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Wisconsin Department of Revenue. Businesses
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Wisconsin Department of Revenue. Sales and Use Tax Permits
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Wisconsin Department of Revenue. Remote Sellers – Wayfair Decision
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Wisconsin One Stop Business Portal. Opening Your Business
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Wisconsin Department of Revenue. BTR-101 Application for Wisconsin Business Tax Registration
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Wisconsin One Stop Business Portal. Wisconsin One Stop Business Portal
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Wisconsin Department of Revenue. Business Tax Registration
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Wisconsin State Legislature. Wisconsin Administrative Code Tax 11.54(2) – Violation
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Wisconsin Department of Revenue. Successor Liability and Clearance Certificates