Employee ID Number

Recommended by IRS

Employer Identification Number

Information about Employer Identification Numbers (EIN), also known as a Federal Tax Identification Number. An EIN is used to identify a business entity.

Apply for an Employer Identification Number (EIN) online
Information about how to apply online for an Employer Identification Number.
Do you need a new EIN?
Generally, businesses need a new EIN when their ownership or structure has changed.

Understanding Your CP518 Business notice

The CP518 Business Notice is a final reminder that we still have no record that you filed your prior tax returns. The Spanish version of this notice is CP618.
General Information
Businesses

QI System Update

New QI System Update page
General Information
Corporations

ExSTARS topics

ExSTARS FAQs
General Information
Small Businesses

Checklist for starting a business

Most businesses start out small. The checklist below provides the basic steps you should follow to start a business.
General Information
Small Businesses

IRS highlights information and free resources in recognition of National Small Business Week

IR-2023-93, April 28, 2023 — As part of National Small Business Week, April 30 to May 6, the Internal Revenue Service is highlighting tax benefits and resources to help those looking to start a business.
News
News Media, Small Businesses

Businesses with employees

Review tax-related responsibilities for businesses with employees.
General Information
Small Businesses

What is a CAF number?

A CAF number is a unique nine-digit identification number assigned the first time you file a third-party authorization with the IRS. Learn more.
General Information
Small Businesses

Reporting Agents File (RAF)

Reporting Agents have long served an important role in our nation’s tax collection system as a conduit between employers and the IRS. Reporting Agents improve the efficiency of IRS tax collection and compliance.
General Information
Small Businesses

Limited liability company - Possible repercussions

Issues Limited Liability Companies may face.
General Information
Small Businesses

IRS reminder: Important backup withholding deadlines

FS-2023-03, Jan. 2023 — Some businesses and other payers withhold money from payments they made to certain people to satisfy backup withholding. These entities should remember their upcoming filing deadlines.
General Information
Businesses