How to Find Your Business License Number: EIN, State, and Local

To find your business license number, look at the original certificate or notice from the agency that issued it. The catch is that “business license number” isn’t one thing. A single business can hold a federal tax ID, a state entity registration number, a professional license, a sales tax permit, and a city or county operating permit all at once, each with its own number and its own issuing office. Figuring out how to find your business license number starts with identifying which one someone is actually asking for.

Identify Which Number You Need

Context usually tells you. A bank opening a business account almost always wants your Employer Identification Number from the IRS. A wholesale vendor asking for a sales tax ID wants the number from your state tax authority. A client verifying your contractor’s license wants the number from the state board that regulates your trade.

The common ones:

  • Employer Identification Number (EIN), your federal tax ID from the IRS.
  • State entity registration or file number, assigned by the Secretary of State when you formed your LLC, corporation, or partnership.
  • Professional or occupational license, issued by a state board for regulated fields like medicine, law, real estate, or contracting.
  • Sales tax permit or seller’s permit, issued by the state Department of Revenue or equivalent.
  • Local business license or operating permit, issued by the city or county.
  • Federal industry license, required only for certain regulated activities.

Once you know which number you’re after, you know which agency’s records to search.

Check Your Own Files First

Most people find the number within five minutes by looking at paperwork they already have. Before calling anyone or opening a search portal, check:

  • The original license or permit certificate, physical or digital.
  • Renewal notices from the issuing agency.
  • The application confirmation or receipt you received when you first applied.
  • Prior tax filings. Business income tax returns, sales tax filings, and payroll filings reference the relevant numbers.
  • Bank account paperwork, because you provided identification numbers when you opened the account.

If an accountant, attorney, or business partner handled the original filing, they likely have the number in their records. Accountants in particular tend to keep copies of every license and filing on behalf of clients.

Recovering Your EIN

The EIN is the number people lose track of most often, and the IRS does not offer a public online lookup for it. The agency assigns it once, when you submit Form SS-4, and it stays with the business permanently.

To recover a lost EIN:

  • Find your CP 575 notice. The IRS mailed this confirmation when it first approved your EIN, and the number is printed on it.
  • Look at any federal business tax return you’ve filed. The EIN appears on every one.
  • Ask your bank. The EIN was collected when you opened your business account.
  • Call the IRS Business and Specialty Tax Line at 800-829-4933, Monday through Friday, 7 a.m. to 7 p.m. local time. After verifying your identity, an agent can provide the number by phone. You can also request Letter 147C, a formal written confirmation of your previously assigned EIN.
  • Request an entity tax transcript, which lists the EIN along with other information on file.

Only an authorized person, such as a principal officer or the responsible party listed on the original EIN application, can request the number from the IRS.1Internal Revenue Service. Employer Identification Number

State-Issued Numbers

Entity Registration Number

When you formed your LLC, corporation, or partnership, the state assigned an entity or file number. This confirms your business is legally registered with the state, but it isn’t the same as an operating license and doesn’t satisfy other licensing requirements.2U.S. Small Business Administration. Register Your Business

Nearly every Secretary of State website has a free business entity search. You can usually look up a business by name and see the entity number, current status (active, dissolved, suspended), registered agent, and filing history. If you formed the business in one state and registered to do business in another, check both.

Professional or Occupational License

Each state licensing board keeps its own records. Most boards run online verification tools where anyone can search by name or license number to confirm status, expiration date, and any disciplinary actions. Go directly to the board that oversees your profession. If you’re not sure which one that is, your state’s Department of Consumer Affairs or equivalent umbrella agency can point you to the right board.

Sales Tax Permit

Your sales tax permit number, sometimes called a seller’s permit or resale certificate number, comes from your state Department of Revenue, Department of Taxation, or equivalent. Most of these agencies have a search function on their website that lets you verify a sales tax ID by business name. The number also appears on the original permit certificate and on any correspondence from the tax agency.

Local Business Licenses

Cities and counties issue their own operating licenses, and the search process varies widely by jurisdiction. Some run fully searchable online databases. Others still keep records on paper at the city clerk’s or county recorder’s office.

Start on your city or county government website. Look for a business licensing department, business tax office, or city clerk page. Many portals let you search by business name, owner name, or address. If there’s no online tool, call the local business licensing office or city hall directly and have the business name, address, and owner name ready.

Some jurisdictions charge a fee for certified copies. If you need a physical replacement certificate mailed to you, plan for at least one to two weeks.

Federal Industry Licenses

Most small businesses don’t need a federal license. If yours operates in a regulated industry, though, the license was issued by a specific federal agency, and that agency maintains its own searchable database. Regulated industries include agriculture, alcoholic beverages, aviation, firearms and explosives, commercial fishing, maritime transportation, mining and drilling on federal lands, nuclear energy, and radio and television broadcasting.3U.S. Small Business Administration. Apply for Licenses and Permits

The FCC, for example, runs more than 40 specialized search databases for broadcasting and communications licenses, including the Universal Licensing System, where you can search by call sign, file number, or licensee name.4Federal Communications Commission. Search FCC Databases The Bureau of Alcohol, Tobacco, Firearms and Explosives, the Federal Aviation Administration, and other agencies each publish their own search tools. If you don’t know which agency licenses your industry, the SBA maintains a directory that matches business activities to the correct federal agency.3U.S. Small Business Administration. Apply for Licenses and Permits

If the Search Turns Up Nothing

If nothing surfaces at any level, one of two things is happening: you never obtained the license, or it lapsed. Both create real exposure. Operating without a required license can bring fines, forced closure, backdated fees, and denial of future applications. In many jurisdictions, contracts entered into by an unlicensed business may be unenforceable, which can mean losing the ability to collect payment for work already completed.

There is no universal grace period. You’re expected to hold the license before you begin operating. If you spot a gap, contact the issuing agency quickly. Many agencies offer a reinstatement or late-renewal path that is simpler and cheaper than a fresh application, particularly when the lapse is recent. The longer it sits, the harder and more expensive it gets to fix.