When Should I Apply for an EIN Number?
Find out when to apply for an EIN number — at formation, before hiring, or when your business structure changes. Learn how to apply online, by fax, or by mail.
Bizee Editorial Staff
Editorial Team
Introduction
The best time to apply for an Employer Identification Number (EIN) is when you form your business entity — but you can apply before or after formation depending on what you need. Most businesses need an EIN before opening a bank account, hiring employees, or filing a business tax return.
What is an EIN?
An Employer Identification Number (EIN) is a 9-digit tax ID the IRS assigns to a business. It works like a Social Security number for your business — identifying it on federal tax filings, bank account applications, and payroll records. Corporations, partnerships, and LLCs are all required to have one.
Sole proprietors without employees generally don't need an EIN unless they elect to be taxed as a corporation or form a partnership. If you're running a single-member LLC, you'll need an EIN to open a business bank account and file certain tax forms — even if you have no employees.
When should you apply for an EIN?
Apply for an EIN at formation or before you need it for a specific task — whichever comes first. Most banks require an EIN to open a business bank account, so if that's your next step, get your EIN before you walk in. The same goes for hiring your first employee or filing a business tax return.
When you form an LLC or corporation
Forming an LLC or corporation is the most common trigger for getting an EIN. The IRS requires one for any business entity — and you'll need it before you can open a business bank account, apply for business licenses, or file your first business tax return. Getting your EIN at formation means you're not scrambling for it later.
When you hire your first employee
You need an EIN before you start paying wages to any employee — including household employees. Without one, you can't run payroll, withhold taxes, or file the required employer tax forms. Apply before your first hire, not after.
When your business structure changes
A new EIN is required when your business changes its legal structure. If a sole proprietorship incorporates, if a partnership becomes a corporation, or if a corporation elects S Corporation status, the IRS treats it as a new entity — and that new entity needs its own EIN. Your old EIN doesn't carry over.
How to apply for an EIN
You can apply for an EIN online through the IRS website, by fax, or by mail using Form SS-4. Online is the fastest option — the IRS issues your EIN the same day. Fax applications take 2 to 4 weeks. Mail applications can take up to 4 weeks. There's no fee to apply directly through the IRS.
Most business owners apply online because the turnaround is immediate. If you're in the middle of forming your LLC and need an EIN to open a bank account or sign a lease, the online application at irs.gov/ein gets it done the same day. The form asks for basic information about your business structure, ownership, and reason for applying.
- Online at irs.gov/ein — same-day EIN, no fee
- Fax using Form SS-4 — 2 to 4 weeks
- Mail using Form SS-4 — up to 4 weeks
FAQ
Generally, get an EIN when you form your business entity or before you need it for a specific task — whichever comes first. Most businesses need an EIN before opening a bank account, hiring employees, or filing a business tax return. Applying at formation means you won't hit a delay when those tasks come up.
Yes. The IRS doesn't require your LLC to be fully approved before you apply for an EIN. You can apply as soon as you've decided on your business structure. That said, most banks will want to see your approved formation documents alongside your EIN before opening a business bank account, so the two steps usually happen close together.
It depends. Sole proprietors without employees generally don't need an EIN — they can use their Social Security number for tax purposes. But you'll need an EIN if you hire employees, elect to be taxed as a corporation, or form a partnership. Getting an EIN also keeps your Social Security number off business documents, which is worth considering.
Yes. A new EIN is required when your business changes its legal structure. Converting a sole proprietorship to a corporation, incorporating a partnership, or electing S Corporation status all require a new EIN. The IRS treats a structural change as a new entity, so your existing EIN doesn't carry over.
Online applications through the IRS are processed the same day — you get your EIN immediately after completing the form. Fax applications using Form SS-4 take 2 to 4 weeks. Mail applications can take up to 4 weeks. If you need your EIN quickly, apply online at irs.gov/ein.
You'll need an EIN to open a business bank account, run payroll, file business tax returns, apply for business licenses, and work with vendors who require a tax ID. It also keeps your Social Security number off business documents — a practical reason to get one even if you're not required to.
