How to Get an EIN for Your New Accounting or Bookkeeping Firm

An EIN (Employer Identification Number) is a free nine-digit number the IRS issues to identify your business for tax purposes. It's not the same as a business license, and it's not required for every firm, but most new practices end up needing one within the first year, usually the moment they open a business bank account or hire their first contractor.

Do you actually need one?

If you're a true sole proprietor with no employees, no contractors you'll issue 1099s to, and you plan to file taxes under your own Social Security number, you can technically operate without an EIN. In practice, most solo practitioners get one anyway for two reasons: banks generally want one to open a business account, and using an EIN instead of your SSN on client-facing invoices and W-9s is a meaningful privacy improvement. If you've formed an LLC, S-corp, or partnership, or if you'll have even one employee or contractor, an EIN is required, not optional.

Apply directly through the IRS, not a third-party site

The EIN itself is always free. The IRS's own online application is the fastest legitimate path: it's available directly through the IRS EIN Assistant, and for most single-owner entities it issues the number instantly at the end of the session, with a downloadable confirmation letter (the CP 575). A number of paid third-party sites will file this on your behalf for a fee; there is no situation where that's necessary for a straightforward domestic firm.

What you'll need before you start the application

• Your legal business name and, if applicable, your registered DBA / trade name
• The entity type (sole proprietorship, single-member LLC, multi-member LLC, S-corp, partnership)
• The responsible party's legal name and SSN or ITIN, this is typically you as the owner
• A U.S. mailing address for the business
• The reason you're applying (started a new business is the standard answer for a new firm)

The online session is a one-sitting form; the IRS system times out after 15 minutes of inactivity per screen, so gather this information before you start.

A timing note that trips people up

The IRS online EIN application is only available Monday through Friday, 7 a.m. to 10 p.m. Eastern. If you're applying outside those hours or you're a non-U.S. applicant without an SSN or ITIN, you'll need to apply by fax or mail using Form SS-4 instead, which takes days to weeks rather than minutes.

After you have it

Use the EIN on your business bank account application, on the W-9 you send clients who need one for their own 1099 reporting, and on any 1099-NEC forms you issue to contractors. Keep the CP 575 confirmation letter; several banks and payment processors ask for it directly rather than just the number.