When You Must Apply for a New EIN

Jan. 17, 2026, 6:04 p.m.
An Employer Identification Number (EIN) is issued by the IRS to identify a business for tax purposes. While many business changes do not require a new EIN, certain structural or ownership changes do require you to apply for a new one.
When You Must Apply for a New EIN

Situations That REQUIRE a New EIN

1. You Change Your Business Structure

A new EIN is required when your legal entity type changes, such as:

  • Sole proprietorship → LLC or corporation

  • Partnership → corporation

  • LLC taxed as a sole proprietor → corporation

  • Corporation → partnership

Reason: The IRS considers the new structure a new tax entity.


2. You Incorporate a Business

If you previously operated as:

  • A sole proprietor, or

  • A partnership

and then incorporate, you must obtain a new EIN for the corporation.


3. A Partnership Ends and a New One Begins

A new EIN is required if:

  • A partnership terminates

  • One partner buys out the others

  • A new partnership is formed with different ownership


4. You Purchase or Inherit an Existing Business

You must apply for a new EIN if:

  • You buy a business and do not operate it as the same legal entity

  • You inherit a business and restructure ownership

The EIN does not transfer to the new owner.


5. You Start a Trust or Estate

Each trust or estate requires its own EIN, even if it’s connected to an existing business or individual.


6. A Single-Member LLC Elects Corporate Taxation

If a single-member LLC elects to be taxed as:

  • A C corporation, or

  • An S corporation

A new EIN is required for IRS filing purposes.


7. Bankruptcy Estates

A business bankruptcy estate (Chapter 7 or 11) must obtain a new EIN, separate from the business owner’s EIN or SSN.


Situations That Do NOT Require a New EIN

You typically do NOT need a new EIN if:

  • You change your business name

  • You change your business address

  • You add a new location

  • You hire employees for the first time

  • Ownership changes within the same LLC or corporation

  • A single-member LLC adds members and becomes a partnership (in some cases—IRS notification required)


EIN Changes by Business Type (Quick Reference)

Business Type New EIN Required?
Sole Proprietor → LLC Yes
LLC → Corporation Yes
Partnership with same partners No
Corporation name change No
Owner changes (same entity) No
New trust or estate Yes

Common Mistakes to Avoid

  • Continuing to use an old EIN after incorporating

  • Using a seller’s EIN after buying a business

  • Applying for multiple EINs unnecessarily

  • Failing to notify the IRS of changes that don’t require a new EIN


How to Apply for a New EIN


Final Thoughts

You must apply for a new EIN whenever the IRS considers your business a new tax entity. If you’re unsure, it’s best to confirm before filing taxes, opening bank accounts, or issuing payroll.

 

 When You Must Apply for a New EIN