Where It Is Already Written Down
Your EIN appears on more paperwork than you would guess. Before calling anyone, check:
- The CP575 confirmation letter. The IRS mailed (or displayed, if you applied online) this notice the day the EIN was assigned. Search your email for a saved PDF titled CP575 or EIN confirmation.
- Any filed business return. The EIN prints at the top of a Form 1120-S, 1065, or on the Schedule C attachments your preparer filed.
- Bank paperwork. The business checking application required the EIN; the bank can also read it back to you from your account profile.
- Payroll and state filings. Form 941s, W-2s you issued, state registration accounts, and payroll provider dashboards all carry it.
- A prior 1099. If a client collected a W-9 from your business, the copy you kept shows the EIN you gave them.
If Nothing Turns Up, Call the IRS
The Business and Specialty Tax Line is 800-829-4933, open 7am to 7pm local time, Monday through Friday. An owner, officer, or other authorized person verifies identity and the IRS reads the EIN over the phone. There is no online EIN lookup for your own number, and there is no fee; any website charging to recover an EIN is a middleman you do not need.
Not Sure You Ever Had One?
Plenty of single-member LLC owners never applied, because an LLC with no employees can ride on the owner's Social Security number for a while. Two quick tells: if you have a business bank account, you almost certainly used an EIN to open it; and if you ever ran payroll, an EIN definitely exists. If neither is true and no CP575 exists in your records, you likely never applied.
Applying is free and takes minutes on the IRS website (search for the EIN online assistant on irs.gov); the number is issued immediately at the end of the session. You will want one before an S corp election, payroll, or business banking, and to keep your Social Security number off W-9s you hand to clients.
Keep It From Getting Lost Again
Store the CP575 (and the CP261 S corp acceptance letter, if you have one) in the same folder as your operating agreement. Those few pages answer nearly every identity question a bank, payroll provider, or state agency will ever ask your business.