EIN Guide for a Delaware Corporation — How to Get Your Federal Tax ID

An Employer Identification Number is a nine-digit number the IRS assigns to identify a business for federal tax purposes. Think of it as a Social Security number for your corporation. It appears on the corporation's tax returns, its payroll filings, and the paperwork you hand a bank to open the corporate account.

Why a corporation always needs one

A corporation is a separate taxpayer. Unlike a single-member LLC — which can sometimes use the owner's SSN because the IRS disregards it — a corporation files its own federal return: Form 1120 for a C corporation, Form 1120-S for an S corporation. That return needs the corporation's own tax ID, so an EIN isn't optional for a corporation the way it can be for a solo LLC. You'll need it from the start.

What you'll use it for

• Filing the corporation's federal income tax return
• Opening the corporate bank account (banks require it)
• Running payroll and filing employment taxes if you have employees
• Making the S corporation election on Form 2553, which references the EIN
• Applying for business licenses and setting up merchant or vendor accounts

Timing matters. Apply for the EIN after your Delaware corporation is formed — after the Division of Corporations has processed your Certificate of Incorporation and the corporation legally exists. The EIN application asks for the entity's legal name and formation details, so you want the corporation actually on file first.

Applying before the corporation exists, or applying under a name that doesn't match your filed certificate, creates mismatches that cause headaches later — a bank that can't reconcile the EIN with the corporate record, or an IRS record tied to the wrong name. Form the corporation, confirm the exact legal name on the accepted certificate, then apply for the EIN using that precise name.

The IRS issues EINs directly and for free. You never need to pay a third party for the number itself — anyone charging you specifically for "getting an EIN" is charging for something the IRS provides at no cost.

The online application (fastest)

If the responsible party has a US Social Security number or ITIN, apply online through the IRS EIN Assistant at IRS.gov. The process:

• Takes about ten minutes in a single session (the tool times out if you pause too long, so have your details ready)
• Requires the corporation's legal name exactly as filed, formation state (Delaware), and the responsible party's information
• Issues the EIN immediately on completion — you can download the confirmation letter (CP 575) and use the number the same day

Applying without a US SSN or ITIN

Many Delaware corporations have foreign founders, and Delaware imposes no residency requirement, so this is a common situation. If the responsible party has neither an SSN nor an ITIN, you can't use the online tool. Instead:

• Complete Form SS-4 (the EIN application)
• Submit it by fax or mail to the IRS
• Wait for the IRS to process it and issue the EIN — fax is faster than mail, but both take longer than the instant online route

International applicants can also apply by phone in some cases. The key point: not having an SSN doesn't prevent a foreign founder from getting an EIN for a Delaware corporation — it just changes the method and adds time.

Every EIN application names a responsible party — the individual who ultimately owns or controls the corporation, or exercises effective control over it. For a startup, this is usually a founder or the principal officer.

What to know about the responsible party

• It must be a natural person (a human), not another entity, in the ordinary case
• The IRS uses this to know who's genuinely behind the corporation
• If the responsible party changes later — say control shifts after a financing — you're expected to update the IRS using Form 8822-B

Choose the responsible party thoughtfully at application time. It should be someone with real authority over the corporation, and their information needs to be accurate, because it ties the EIN to a specific accountable person.

A few errors come up again and again, and all of them are avoidable.

Paying for something free

The number one mistake is paying a service specifically for "obtaining your EIN." The IRS issues it free. A legitimate formation service may include EIN assistance as part of a broader package, which is fine — but the EIN itself has no IRS cost, and you should never be charged a standalone fee for the number.

Applying before the corporation exists

Get the EIN after your Certificate of Incorporation is accepted, using the exact legal name on file. Jumping ahead creates name-mismatch problems with the IRS and your bank.

Getting more than one

A corporation needs exactly one EIN. If you apply twice, or apply then re-apply because you didn't save the confirmation, you can end up with duplicate numbers and a tangled IRS record. Save the CP 575 confirmation letter the moment you receive it — it's your proof and you'll need it for the bank.

Name or responsible-party mismatches

The name on the EIN application must match your filed certificate, and the responsible party's details must be accurate. Mismatches surface at the worst times — when a bank or the IRS can't reconcile your records — so get them right the first time.