To get a state tax ID number, you apply through your state’s department of revenue or taxation, usually online, using your federal Employer Identification Number and basic details about your business and its owners. Most states process the application within a few business days and charge nothing, or very little, for the registration itself. What agencies you register with, and how many separate accounts you end up with, depends on whether you have employees, sell taxable goods or services, and how your business is organized.
Do You Actually Need a State Tax ID
Not every business needs one. Three situations are the usual triggers:
- You hire employees in the state. Once you bring on even one, you generally have to register for payroll tax withholding and unemployment insurance with the state’s revenue and labor agencies.
- You sell taxable goods or certain services. That requires a seller’s permit or sales tax license from the state where the sale takes place, and the permit comes with a state tax account number.
- You operate as a corporation, LLC, or partnership. Many states require formal entities to register for state income tax, franchise tax, or both, whether or not there are employees or sales tax to collect.
A sole proprietor with no employees who doesn’t sell taxable goods often needs nothing separate at the state level. The owner’s Social Security number covers state income tax. The moment you hire someone or start collecting sales tax, that changes.
One boundary worth knowing: Alaska, Delaware, Montana, New Hampshire, and Oregon have no state sales tax. If you operate only in one of those states and have no employees, your state registration duties may be minimal. You’ll still want to check whether the state requires separate registration for income tax or other business taxes.
Whether you end up with one number or several also varies. Some states issue a unified business tax ID covering sales tax, withholding, and corporate income tax. Others split those across separate agencies with separate applications. Your state’s revenue website will route you to the right ones based on how you answer the initial questions.
Get Your Federal EIN First
Almost every state application requires your federal Employer Identification Number. States use it to link your state accounts to your federal records.
The IRS issues EINs for free at irs.gov. The online application takes about 10 to 15 minutes, and if approved, you get the number at the end of the session. You’ll need the Social Security number or ITIN of the responsible party who controls the business, and your business entity type. The application can’t be saved partway through and expires after 15 minutes of inactivity, so pull your information together before you start.1Internal Revenue Service. Get an Employer Identification Number
The IRS limits applications to one per responsible party per day, so if you’re forming multiple entities, spread them out. You can also apply by mail or fax using Form SS-4, though the mail route takes up to four weeks.2Internal Revenue Service. Employer Identification Number
What to Have Ready Before You Apply
State forms vary in layout but ask for the same core information. Gathering it up front avoids the delays that come from stopping mid-application:
- Your federal EIN, the nine-digit number issued by the IRS.3Office of the Law Revision Counsel. 26 USC 6109 – Identifying Numbers
- Your legal business name, matching your articles of incorporation, articles of organization, or other formation documents exactly. A mismatch causes rejections.
- Your business structure: sole proprietorship, single-member LLC, multi-member LLC, partnership, S-corporation, or C-corporation. This determines which tax accounts apply and how often you’ll file.
- Owner and officer details: Social Security numbers, home addresses, and titles for each owner, partner, or corporate officer. States use these to identify the individuals personally responsible for the business’s tax obligations.
- Your physical business address and the date you started, or will start, doing business in the state.
- Your six-digit NAICS code, which identifies your industry and helps the state apply the right tax rates. You can look yours up at the Census Bureau’s website.
- Estimated monthly gross sales or payroll. States use these projections to assign your filing frequency.
Both the IRS and state agencies also require you to name a “responsible party” on the application. This is the individual with authority over the business’s finances, and in many states that person can be held personally liable for unpaid sales or payroll taxes even when the business is an LLC or corporation. For a sole proprietorship it’s the owner; for a corporation or LLC it’s typically an officer, managing member, or partner with authority over tax collection and payment. Changing the responsible party later usually requires formal notification to the state, so get the designation right the first time.
Submitting the Application
Nearly every state now takes registrations through an online portal on its department of revenue or taxation website. You create an account, work through the business registration form, and submit electronically. You’ll usually get a confirmation number immediately and the account itself within a few business days. Paper applications still exist in most states, but staff have to key them in by hand, so they can take several weeks. Most states charge no fee for the initial sales tax registration, though a few require a small refundable security deposit.
A few things that catch people out:
- Match names character for character. Your legal name on the state application has to match your EIN records and your formation documents exactly. “LLC” versus “L.L.C.” has caused more rejections than anyone wants to admit.
- Register before you start collecting. Collecting sales tax without a valid permit is illegal in most states, even if you plan to remit every dollar.
- Watch for multiple applications. If your state splits administration across agencies, you may need one filing for sales tax, another for employer withholding, and a third for corporate income or franchise tax.
If You Sell Into Other States
If you sell products or services into states where you have no physical presence, you may still have to register there for sales tax. After the Supreme Court’s 2018 decision in South Dakota v. Wayfair, nearly every state with a sales tax now imposes an economic nexus rule on remote sellers.
The common threshold is $100,000 in annual gross sales into a state. Some states set it higher: California and Texas use $500,000, and New York uses $500,000 combined with more than 100 transactions. Some states also apply a transaction count (often 200 separate sales), though many have dropped that piece in recent years. Thresholds are typically measured over the current or preceding calendar year.
If you’re selling into many states, the Streamlined Sales Tax Registration System lets you register for sales tax across more than 20 states through a single free application. Full member states include Arkansas, Georgia, Indiana, Iowa, Kansas, Kentucky, Michigan, Minnesota, Nebraska, Nevada, New Jersey, North Carolina, North Dakota, Ohio, Oklahoma, Rhode Island, South Dakota, Utah, Vermont, Washington, West Virginia, Wisconsin, and Wyoming.4Streamlined Sales Tax. Sales Tax Registration SSTRS A state may still charge a fee if you’re legally required to register there. You file returns and pay tax directly with each state; SSTRS only centralizes the initial registration.
Crossing an economic nexus threshold without registering can trigger back taxes, penalties, and interest calculated from the date you should have started collecting. Tracking sales by state is an ongoing job, not a one-time check.
After You’re Approved
Once approved, the state issues a certificate or notification with your tax ID number. That number goes on every return, every payment, and every piece of correspondence with the revenue department. Many states require businesses with sales tax permits to display the certificate at the place of business where customers can see it.
The state also assigns a filing frequency, based on your estimated tax volume: monthly, quarterly, or annually. Higher volume means more frequent filing. Missing a deadline triggers late penalties and interest even if you owe nothing that period. In many states you have to file a return for every active period, including periods with zero sales. Skipping a zero-dollar return generates automatic penalty notices that are tedious to unwind.
You’re also required to tell the state about changes that affect your account: a new business address, opening or closing a location, a change in ownership or the responsible party, or converting your entity type (a sole proprietorship becoming an LLC, for instance). Unreported changes lead to misallocated payments, mail going to the wrong place, and problems during audits.
One useful side benefit of an active sales tax permit: you can typically issue resale certificates to your suppliers when buying inventory you intend to resell, letting you purchase those goods tax-free because you’ll collect sales tax from the end customer. Without an active sales tax account, you generally can’t make tax-exempt resale purchases. Using a resale certificate for items you actually consume in your business is a common audit trigger and carries penalties.