A seller’s permit number is the state-issued identifier that authorizes your business to collect sales tax from customers and sends your remittances to the right account in the state’s tax system. If you sell taxable goods or services in any of the 45 states (plus the District of Columbia) that levy a statewide sales tax, you generally need one before you make your first sale. The permit is usually free, applications take a few days to a few weeks to process, and the number stays with your business as long as you keep selling.
What the Number Actually Does
When a state issues you a seller’s permit, it’s deputizing your business as a tax collector. On every taxable sale, you add the applicable sales tax to the customer’s total, hold that money separately, and send it to the state on a schedule the state assigns you. The unique number tied to your account is how the state matches your returns and payments to your business.
It’s not the same as your federal Employer Identification Number, which the IRS uses for income tax and payroll.1U.S. Small Business Administration. Get Federal and State Tax ID Numbers It’s also not the same as a city or county business license, which just grants permission to operate in a municipality. The seller’s permit is specifically about state sales tax.
The name changes depending on where you register. California issues a Seller’s Permit. New York calls it a Certificate of Authority. Texas uses Sales Tax Permit. You’ll also see Sales and Use Tax License, Retail License, and Vendor Registration in other states. The function is identical.
Who Needs One
If you sell physical goods or taxable services to customers in a state with a sales tax, you almost certainly need to register there. That covers brick-and-mortar shops, online stores, and part-time operations run out of a garage. Even temporary sellers at flea markets, craft fairs, and holiday pop-ups usually need a permit.
Five states have no statewide sales tax: Alaska, Delaware, Montana, New Hampshire, and Oregon. If your business operates only in one of those, you don’t need a seller’s permit for state sales tax. Alaska is a partial exception because some local jurisdictions there impose their own sales taxes.
Physical Presence
The traditional trigger is having a physical connection to the state, what tax authorities call nexus. A storefront, warehouse, office, inventory in a fulfillment center, or an employee working in the state all establish nexus and bring you under that state’s sales tax rules.
Economic Nexus
Since the Supreme Court’s 2018 decision in South Dakota v. Wayfair, states can require out-of-state sellers to collect sales tax based on sales volume alone, with no physical presence required.2Supreme Court of the United States. South Dakota v. Wayfair, Inc., 585 U.S. ___ (2018) The most common threshold is $100,000 in annual sales into a state. Some states also use an alternative threshold of 200 separate transactions, though more than 15 states have dropped the transaction count and now look only at dollars.
If you ship to customers in many states, you can trip economic nexus in several of them at once. Each state where you cross the threshold needs its own registration. Track your state-by-state sales as you approach $100,000 anywhere.
The Marketplace Exception
If you sell through Amazon, Etsy, eBay, Walmart Marketplace, or a similar platform, the platform itself collects and sends in sales tax on your behalf in most states. These are marketplace facilitator laws, and virtually every sales-tax state has one. The platform, not you, is legally responsible for the tax on orders placed through it.
Practically, that means if all your sales go through a marketplace facilitator, you often don’t need to register separately in states where the platform already collects. Those marketplace sales also typically don’t count toward your economic nexus threshold. But sales through your own website or at in-person events do count, and you’ll still need permits in any state where those direct sales cross the threshold on their own.
How to Apply
Apply through the state tax agency, usually called the Department of Revenue, Department of Taxation, or Comptroller. Most states offer online registration, and the form itself takes 10 to 30 minutes once you have your details ready.
Expect the application to ask for:
- Your legal structure (sole proprietor, LLC, corporation, partnership)
- Your federal EIN, or a Social Security Number if you’re a sole proprietor without an EIN
- Your business address and any additional locations where sales happen
- An estimate of your sales volume, which the state uses to set your filing schedule
- Your business start date, or the date you plan to begin selling
Most states issue the permit for free. Roughly a dozen charge a fee, generally $5 to $100, and it’s usually a one-time charge. Online filings often clear within a few business days and sometimes instantly. Paper applications by mail can take six to eight weeks.
Some states require a security deposit or surety bond before issuing a permit, especially if the applicant has a history of tax delinquency or no established credit. The deposit protects the state if you collect tax but fail to remit it, and the amount is typically a multiple of your estimated monthly tax liability, often two to six months’ worth.
Using the Number to Buy Inventory Tax-Free
The permit number also lets you buy inventory for resale without paying sales tax on it. You give your supplier a resale certificate that includes your permit number, a description of the goods, and a statement that you’re buying them for resale. The supplier then skips the sales tax on that purchase, because the tax will be collected when you sell the item to the end customer.
The resale exemption only applies to goods you actually plan to resell. Buying office supplies or equipment for your own use and claiming the exemption means you owe use tax on those purchases, and that’s one of the first things auditors look for. Suppliers are required to keep completed resale certificates on file; if one can’t be produced during an audit, the state treats the sale as taxable and the supplier owes the uncollected tax.
Filing, Records, and Penalties
The state assigns a filing frequency based on your expected volume. High-volume sellers file monthly, moderate-volume sellers file quarterly, and small operations may file annually. The state tells you your schedule after approving your permit and can adjust it as your real numbers come in. Every return runs on your permit number, and returns are due on the assigned date even in periods when you had zero taxable sales. Skipping a zero-dollar return is a common way to pick up late-filing penalties.
Keep records of all sales, tax collected, exemption certificates you accepted, and returns you filed. Most states require retention for at least three to four years after the related return is filed, with longer periods if a liability is under review.3Internal Revenue Service. How Long Should I Keep Records During an audit, you have the burden of proving a tax-exempt sale was legitimate, and without the paperwork the state will treat it as taxable.
Operating without a required permit carries real consequences. Penalties can include daily fines, back taxes on every sale you should have taxed, interest, and in serious cases criminal prosecution. Late filing or underpayment also brings its own penalties, commonly 5% to 10% of the unpaid tax for the first month and climbing from there. The worst position is collecting sales tax from customers and failing to send it in: states treat that money as trust funds belonging to the government, and owners can be held personally liable even if the business is an LLC or corporation.
Keeping the Permit Current
In most states, your permit stays valid indefinitely while your business is active, with no annual renewal. A few states are exceptions. Colorado, for instance, requires renewal every two years, so check the rule where you register.
If your legal structure, ownership, or location changes, you’ll usually need to update your registration or apply for a new permit. Selling or transferring the business doesn’t move the permit to the buyer; the new owner has to apply on their own.
When you stop selling, close the permit rather than letting it sit. An open permit means the state still expects returns, and if you stop filing it will assess estimated taxes and penalties against the account. Closing involves a final return through your last day of business, paying any remaining tax, and notifying the state agency. Most states handle this online or by a short phone call. One trap at closing: inventory you bought tax-free using a resale certificate but never sold can trigger use tax, because the exemption only covers goods you actually resell. Anything you keep, give away, or use personally becomes taxable when the business winds down.