Do I Need a New EIN? Rules by Entity Type and Filing Steps

You need a new Employer Identification Number when your business changes its legal structure or ownership in a way the IRS treats as creating a new taxpayer. Incorporating a sole proprietorship, dissolving a partnership, forming a subsidiary, or taking over a business you didn’t previously own all trigger a new EIN. Routine updates — a name change, a new address, an S-corporation election, an LLC changing its tax classification — do not. The specific triggers depend on your entity type.

Sole Proprietors

A sole proprietor needs a new EIN when they incorporate, when they bring in a co-owner and start operating as a partnership, or when they file for bankruptcy. Buying an existing sole proprietorship or inheriting one also requires the new owner to get their own EIN, because the original number is tied to the prior owner’s tax history and cannot transfer. The same is true when a family member takes over from a retiring owner.¹

You do not need a new EIN to change the business name, move locations, or run more than one business under the same sole ownership.

Partnerships

A partnership needs a new EIN when it incorporates, when it ends and a new partnership takes its place, or when it dissolves and one remaining partner continues the business alone as a sole proprietor. That individual then needs an EIN for the sole proprietorship.¹

A partnership does not need a new EIN for a name or location change, for filing bankruptcy, or for an ownership change that doesn’t terminate the partnership. Under federal tax law, a partnership terminates only when it ceases all business activity or when its operations no longer continue in partnership form.² Ordinary ownership changes, on their own, don’t trigger a termination.³

Corporations

A corporation needs a new EIN when it receives a new charter from the secretary of state, when it creates a subsidiary, when it converts to a partnership or sole proprietorship, or when two corporations merge to form an entirely new entity. The new corporation coming out of that merger is a new taxpayer.¹

A corporation keeps its existing EIN for a name or address change, a bankruptcy filing, a divisional restructuring, or an S-corporation election on Form 2553. The surviving corporation in a merger also keeps its number. Reincorporating in a different state while remaining a corporation doesn’t require a new EIN either.

LLCs

An LLC needs a new EIN if it terminates and forms a new corporation or partnership. A single-member LLC that has been using the owner’s Social Security Number needs its own EIN once it has to file excise or employment tax returns.¹

An LLC does not need a new EIN when it changes its tax election, such as choosing to be taxed as a corporation or S-corporation instead of as a partnership or disregarded entity. Federal regulations specifically provide that an entity keeps its EIN when its tax classification changes under the check-the-box rules.⁴ Converting a partnership into an LLC still classified as a partnership, renaming or moving the LLC, or reporting income as a branch or division of another entity all allow the LLC to keep its current number.

Bankruptcy Estates

When an individual business owner files for Chapter 7 or Chapter 11 bankruptcy, the bankruptcy estate is a new taxable entity, separate from the individual. The trustee or debtor-in-possession must get an EIN for the estate and use it on all returns and estimated tax payments filed with the IRS. The debtor’s Social Security Number cannot substitute.⁵

Changes That Do Not Require a New EIN

Many common updates let you keep your current number. Across entity types, you generally do not need a new EIN when you:

Change the business name
Move to a new address or open additional locations
Elect S-corporation status
Change an LLC’s tax classification without dissolving the LLC
Survive a corporate merger as the continuing corporation
Undergo an ownership change that doesn’t terminate the entity

These are record updates, not the creation of a new taxpayer.¹

Reporting a Name Change

A sole proprietor writes to the IRS at the address where they file their return. A corporation checks the name-change box on the appropriate line of Form 1120 or 1120-S when filing a current-year return, or writes to the IRS if the return has already been filed. Partnerships do the same on Form 1065.⁶

Reporting an Address or Responsible Party Change

Use Form 8822-B to report a new business mailing address, business location, or change in the responsible party (the individual who controls, manages, or directs the entity). Any entity with an EIN must report a responsible-party change within 60 days. There’s no penalty for filing late, but if the IRS doesn’t have your current address, you may not receive notices of deficiency or demands for tax, and penalties and interest continue to accrue.⁷

Applying for the New EIN

The fastest way to get an EIN is the IRS online application at IRS.gov, which issues the number immediately on approval. The tool runs Monday through Friday from 6:00 a.m. to 1:00 a.m. (next day), Saturday from 6:00 a.m. to 9:00 p.m., and Sunday from 6:00 p.m. to midnight, all Eastern Time. You have to finish in one session, and the application times out after 15 minutes of inactivity.⁸

If you can’t use the online portal, submit Form SS-4 by fax to 855-641-6935 (typically four business days) or by mail to Internal Revenue Service, Attn: EIN Operation, Cincinnati, OH 45999 (about four weeks).⁹¹⁰ 11

Closing the Old EIN Account

Once you have the new EIN, close the account tied to the old one. The IRS won’t close the account until you’ve filed all required returns and paid any tax owed. Send a letter that includes the business’s full legal name, the EIN being closed, the business address, and the reason for closing. If you still have the original EIN assignment notice, include a copy. Mail it to: Internal Revenue Service, Cincinnati, OH 45999.¹²

1
Internal Revenue Service. When to Get a New EIN
2
Office of the Law Revision Counsel. 26 USC 708 – Continuation of Partnership
3
Internal Revenue Service. Questions and Answers About Technical Terminations, Internal Revenue Code IRC Sec 708
4
eCFR. 26 CFR 301.6109-1 – Identifying Numbers
5
Internal Revenue Service. Publication 908 (2025), Bankruptcy Tax Guide
6
Internal Revenue Service. Business Name Change
7
Internal Revenue Service. Form 8822-B, Change of Address or Responsible Party – Business
8
Internal Revenue Service. Get an Employer Identification Number
9
Internal Revenue Service. Instructions for Form SS-4 (12/2025)
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Internal Revenue Service. Form SS-4, Application for Employer Identification Number
11
Internal Revenue Service. Responsible Parties and Nominees
12
Internal Revenue Service. Closing a Business