An LLC number and an EIN are two different identifiers issued by two different governments for two different purposes. The LLC number is the entity ID your state’s Secretary of State assigns when it approves your Articles of Organization; the EIN is the nine-digit federal tax ID the IRS assigns to your business. They are not interchangeable, and most LLCs end up needing both.
What the LLC Number Is
Your “LLC number” is the identifier the state stamps on your Articles of Organization when it approves the filing. Depending on where you formed, it may appear as a Charter Number, Entity ID, File Number, or Control Number. It carries no federal tax significance.
The state uses this number to track your LLC’s legal standing: whether you’ve filed annual reports, paid any required franchise taxes, and remained in good standing. If you register in a second state to do business there (foreign qualification), that state issues its own separate entity number for the same company. Your EIN, by contrast, stays the same everywhere.
Formation fees to receive a state entity number run from roughly $50 to over $500. Most states also charge a recurring annual or biennial report fee to keep the number active. Missing those filings can lead to administrative dissolution, which ends the LLC’s legal existence and can expose owners to personal liability for business debts.
What the EIN Is
An Employer Identification Number is a nine-digit number formatted XX-XXXXXXX that the IRS assigns to business entities for federal tax purposes. It functions like a Social Security Number for your company, and the IRS uses it to track every return, employment filing, and reporting obligation tied to the business.1Cornell Law School. Employer Identification Number (EIN)
Banks require an EIN to open an account in your LLC’s legal name, and vendors ask for it on Form W-9. Business credit bureaus such as Dun & Bradstreet and Experian Business use the EIN to build your company’s credit profile, which helps separate your personal credit history from business activity.
Once assigned, an EIN belongs to that entity permanently. The IRS cannot cancel it or reissue it to another business. If you close your LLC, you can ask the IRS to deactivate the number, but it will never be recycled.2Internal Revenue Service. If You No Longer Need Your EIN
The Third Number You May Also Need
There’s often a third identifier in the mix. If your state collects income tax, sales tax, or employment taxes, the state’s department of revenue (not the Secretary of State) issues a separate state tax identification number. It’s distinct from both your LLC entity number and your federal EIN.3U.S. Small Business Administration. Get Federal and State Tax ID Numbers
So your LLC could carry three distinct numbers from three different agencies. Use the state entity number for Secretary of State filings, the state tax ID for state tax filings, and the EIN for everything federal. Mixing them up on paperwork is one of the more common compliance mistakes new owners make.
Does Your LLC Need an EIN?
Every LLC that registers with a state gets an entity number automatically as part of formation. An EIN is a separate application, and not every LLC is legally required to have one. A single-member LLC with no employees and no excise tax liability can technically use the owner’s SSN for federal tax purposes.4Internal Revenue Service. Single Member Limited Liability Companies In practice, most of those owners still apply for one to keep their SSN off of vendor forms and bank paperwork.
An EIN becomes mandatory the moment any of the following applies:
- The LLC has two or more members, because it is treated as a partnership for federal tax purposes and must file Form 1065.5Internal Revenue Service. Instructions for Form 1120 (2025)
- The LLC has employees. Even a single-member LLC that is otherwise a disregarded entity must use its own EIN, not the owner’s SSN, for employment tax reporting.4Internal Revenue Service. Single Member Limited Liability Companies
- The LLC elects S-corp treatment on Form 2553 or C-corp treatment on Form 8832, regardless of how many members it has.6Internal Revenue Service. About Form 2553, Election by a Small Business Corporation
- The LLC operates a qualified retirement plan or owes excise taxes such as those on alcohol, tobacco, or firearms.
Single-member LLCs classified as disregarded entities report business income on Schedule C (or Schedule E or F) of the owner’s Form 1040, using the owner’s SSN. If employment or excise taxes enter the picture, the LLC needs its own EIN.4Internal Revenue Service. Single Member Limited Liability Companies
How to Get Each Number
The state entity number arrives as part of LLC formation. You file Articles of Organization with the Secretary of State, pay the filing fee, and the approved filing comes back stamped with your entity ID.
Do that first. The IRS advises completing state formation before applying for an EIN to avoid processing delays.7Internal Revenue Service. Get an Employer Identification Number The EIN application is free and available online at IRS.gov; it takes about ten minutes and delivers the number immediately on approval. Any website charging a fee for this service is unnecessary.
You’ll need the LLC’s legal name, its physical address, and the SSN or ITIN of the responsible party. The responsible party must be an individual, not another business entity, and the IRS defines the role as whoever ultimately owns or controls the LLC and has practical authority over its funds and assets.8Internal Revenue Service. Instructions for Form SS-4 (12/2025) For a single-member LLC, that’s the owner; for a multi-member LLC, it’s typically the managing member.
The online application is the digital version of Form SS-4 and must be finished in one sitting because it cannot be saved. If you prefer paper, faxing Form SS-4 returns an EIN in about four business days; mailing it takes roughly four weeks.9Internal Revenue Service. Employer Identification Number
Keeping Both Numbers Active
Neither number takes care of itself. On the federal side, if the responsible party listed on your EIN application changes, you must file Form 8822-B with the IRS within 60 days. That includes situations where a managing member is replaced or the LLC is sold.10Internal Revenue Service. Form 8822-B, Change of Address or Responsible Party
On the state side, your entity number stays valid only as long as you meet your state’s filing requirements. Most states require annual or biennial reports, with fees ranging from nothing in a few states to several hundred dollars in others. Letting them lapse doesn’t just add late fees; it can trigger administrative dissolution, which strips the LLC of its legal existence and the liability protection that comes with it.
If You Lose Your EIN
Misplacing an EIN is common, especially for businesses that don’t file frequently. Check the original CP 575 notice the IRS sent when the number was assigned, a prior year’s business tax return, or the bank where you opened your business account. State or local licensing agencies where you applied often have it on file as well. If none of that turns it up, call the IRS Business & Specialty Tax Line at 800-829-4933 (Monday through Friday, 7:00 a.m. to 7:00 p.m. local time). After identity verification, they’ll provide the number over the phone. You can also request a formal confirmation by asking for Letter 147C.9Internal Revenue Service. Employer Identification Number