The IRS uses an employer identification number, or EIN, to identify a business entity. This unique nine-digit number is like a Social Security number for companies. Not all businesses need an EIN, but if you have employees or are formed as a corporation, partnership, or multimember limited liability company (LLC), you must apply for one. The IRS offers EINs for free, and if you apply online, you can get your EIN immediately after completing the application.
Contrary to what you might expect, you can't actually change your EIN. It's designed to be a permanent identifier for your business (again, much like a Social Security number). However, you can either correct mistakes in the information tied to an existing EIN or get a new EIN, depending on your business situation.
How to change an incorrect EIN
Mistakes happen, and if you entered your EIN incorrectly on Form SS-4, the EIN application, it’s not the end of the world.
Don't submit a new application if you made a mistake on your original EIN form. Instead, send a signed letter to the IRS explaining the error and providing the correct information. This letter should be on company letterhead, if available, and include:
- The name and SSN of your responsible party.
- The full legal name of your business.
- The correct EIN for your business.
- Your business mailing address.
- The information associated with the EIN number that needs to be changed.
The “responsible party” is the person in charge of your business entity. This person is the one who owns or controls the business. For a corporation, the responsible party is the principal officer. For a partnership, it’s the general partner. For a nonprofit, it’s the executive director or president.
Mail this letter to the IRS address where you file your business tax return. If you're not sure which address that is, you can call the IRS Business and Specialty Tax Line at 800-829-4933, Monday to Friday, 7 a.m. to 7 p.m. local time (note that Alaska and Hawaii follow Pacific time).
[Read more: A Complete Guide to Filing Your Business Taxes]
Utilizing an outdated Employer Identification Number (EIN) can result in significant compliance violations, as regulatory authorities require accurate and current identification for business entities.Aaron Hall, business attorney
What to do while you wait for a new EIN
If you've applied online, you'll have your EIN right away and can use it immediately to open a bank account, apply for business licenses, or file a paper tax return. Be aware that the IRS says it can take up to two weeks before the number is active in its systems; you may need to wait that long before you can e-file a return, make electronic tax deposits, or pass the IRS' Taxpayer Identification Number Matching Service.
How to update your EIN on tax documents
If you’re waiting for an updated EIN and your new number hasn’t arrived by the time your tax return is due, write “Applied For” and the date that you applied for the EIN in the space shown for the number. Again, the IRS reports that it generally takes up to two weeks for EINs to be active for tax-related tasks.
“If you don't have your EIN by the time a deposit is due, send your payment to the service center address for your state. Make your check or money order payable to Internal Revenue Service and show your name (as shown on the SS-4), address, kind of tax, period covered, and the date you applied for your EIN,” wrote the IRS.
When to get a new EIN
The general rule from the IRS is simple: You need a new EIN when your business’s ownership or structure changes. You don’t need a new EIN if you change your business name, add a new location, or bring in a new responsible party.
Beyond that, the specific triggers depend on your entity type. The IRS has a helpful one-pager breaking down events that require an EIN change.
Sole proprietors need a new EIN if they incorporate, form a partnership, or declare bankruptcy. They don't need one if they change the business's name or location or operate multiple businesses.
Corporations need a new EIN if they receive a new charter from the secretary of state, become a subsidiary of another corporation, change to a partnership or sole proprietorship, or merge in a way that creates a new corporation. They don't need to obtain a new EIN if they change their name or location, declare bankruptcy, are the surviving company after a merger, elect to be taxed as an S corporation, or convert at the state level without changing the business structure.
Partnerships need a new EIN if they incorporate, if one partner takes over and operates as a sole proprietor, or if the partnership ends and a new one begins. They don't need one if they change their name or location, declare bankruptcy, or undergo an ownership change that doesn't terminate the partnership.
LLCs need a new EIN if they terminate the existing LLC and form a new corporation or partnership, or if a single-member LLC has to start filing excise or employment taxes. They don't need one if they change their name or location, convert from a partnership to an LLC taxed as a partnership, or change their tax election to a corporation or S corporation.
If you're a sole proprietor converting to a single-member LLC, you can generally keep using your existing EIN as long as you don't hire employees, owe excise taxes, or elect to be taxed as a corporation. If you're converting to a multimember LLC, you'll need a new EIN because the IRS treats it as a partnership.
[Read more: How to Establish and Build Business Credit]
How to change your business name or responsible party
Changing your business name doesn't require a new EIN, but you do need to tell the IRS. The process for a name change depends on your entity type.
- Sole proprietors write to the IRS at the address where they filed their last return. The owner or an authorized representative must sign the letter.
- Corporations check the name change box on their current year Form 1120 (Page 1, Line E, Box 3) or Form 1120-S (Page 1, Line H, Box 2). If you've already filed for the year, write to the IRS at the address where you filed. A corporate officer must sign.
- Partnerships check the name change box on their current-year Form 1065 (Page 1, Line G, Box 3), or if they've already filed, write to the IRS at the address where they filed. A partner must sign.
If you want written confirmation of the name change, ask for it in your letter.
Changing your mailing address, business location, or responsible party is handled differently, with Form 8822-B, Change of Address or Responsible Party – Business. The form is short and covers all three changes. You can't attach it to your return or file it electronically; mail it to the address listed in the form's instructions.
The IRS requires you to report a change in responsible party within 60 days. There's no hard deadline for address changes, but the IRS advises reporting them promptly so notices don't go to the wrong place. If a representative (such as an accountant) signs the form on your behalf, attach a copy of your power of attorney, Form 2848.
What to update after an EIN change
Getting a new EIN is only half the job. Your old number is tied to accounts and registrations across your business, and each one needs to be updated separately. Here's a checklist to work through:
- Your bank. Business checking, savings, and credit accounts are opened under your EIN, so contact your bank to update it. Some banks may require a new account.
- Payroll and your payroll provider. Employment tax deposits and filings such as Form 941 must use the new EIN. If you took over another employer's business, you should use your own EIN, not the prior employer's.
- State and local agencies. Update your state tax registration, business licenses, and permits. Some states issue their own tax ID tied to your federal EIN.
- Vendors, clients, and contractors. Anyone who issues you a Form 1099 needs a new Form W-9 with your updated EIN.
- Retirement plans and benefits. Your plan sponsor records and any employee plan filings should reflect the new number.
- Merchant accounts and payment processors. Payment platforms verify businesses against their EIN and may hold payouts if the number on file doesn't match IRS records.
It’s important to update this information after an EIN change. “Utilizing an outdated Employer Identification Number (EIN) can result in significant compliance violations, as regulatory authorities require accurate and current identification for business entities,” wrote Aaron Hall, a business attorney in Minnesota. “Such inaccuracies often lead to tax filing errors, which may trigger audits, penalties, or delays in processing returns.”
What to do if you lose or misplace an EIN
In the unfortunate event that you misplace an EIN, there are a few options you can try to find it.
Start with the confirmation notice the IRS sent when your EIN was issued (called a CP 575). If you've set up an IRS Business Tax Account, eligible users can download a digital copy of this notice, which the IRS accepts as a substitute for the original.
You would have needed your EIN to open a bank account or to apply for a state or local business license. Contact either your bank or the licensing agency to see if they have your EIN on file. You also need your EIN to file a tax return. Look at previous tax filings to find your EIN.
If none of these options work, call the IRS Business and Specialty Tax Line at 800-829-4933, Monday to Friday, 7 a.m. to 7 p.m. local time. Have an authorized person for your business (such as a sole proprietor, partner, or corporate officer) call the number and verify their identity to receive the EIN. You can also ask the IRS to send Letter 147C, an official EIN verification letter, which banks and vendors will accept in place of the original notice.
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