Getting an EIN for Your Colorado Limited Partnership

An Employer Identification Number, or EIN, is the IRS's nine-digit federal tax identifier for a business. Think of it as a Social Security number for a business — it identifies your limited partnership on tax filings, bank paperwork, and payroll. It's issued at no cost directly by the IRS, and no third party can get you a "better" or "faster" one than the IRS provides for free.

Why a partnership can't skip it

A single-member LLC can sometimes operate on the owner's Social Security number because the IRS treats it as a disregarded entity. A limited partnership can't. A partnership is its own filer — it files a Form 1065 informational return and issues each partner a Schedule K-1 — so it needs its own federal identifier. There's no scenario where a genuine Colorado LP with general and limited partners avoids getting an EIN.

What you'll use it for

• Filing the partnership's annual Form 1065
• Opening a bank account in the partnership's name (banks require it)
• Hiring employees and running payroll
• Registering for Colorado tax accounts, like sales tax, when applicable
• Identifying the partnership on vendor and contractor paperwork

Timing your EIN application correctly avoids a surprisingly common headache: getting an EIN attached to the wrong entity name.

File the certificate first

Apply for the EIN after your Certificate of Limited Partnership is approved by the Colorado Secretary of State, not before. The EIN application asks for the partnership's legal name, and you want that to exactly match the name on your approved certificate. Applying before the entity officially exists risks a mismatch that causes friction when you open a bank account or file taxes.

Then everything else follows

With the certificate approved and the EIN in hand, the rest of setup unlocks: you can open the partnership bank account (which needs both the filed certificate and the EIN), register for any Colorado tax accounts, and set up payroll if you'll have employees. The EIN is the hinge between "the entity exists on paper" and "the entity can actually transact."

The IRS offers several ways to apply, and the online route is by far the fastest for anyone eligible.

Applying online (the fast path)

1. Go to the EIN Assistant on IRS.gov.
2. Select partnership as the entity type — not LLC, not corporation. Choosing the right type ensures the IRS sets up the account correctly for a Form 1065 filer.
3. Enter the partnership's legal name exactly as it appears on the approved Certificate of Limited Partnership, plus its address.
4. Provide the responsible party's information — a general partner or someone with authority over the partnership, along with their SSN or ITIN.
5. Submit. The EIN is issued immediately on screen, and you can download and save the confirmation letter (CP 575) right away.

The online application must be completed in a single session — it times out after inactivity — and it's available during IRS operating hours. The person applying needs a valid SSN or ITIN.

Applying without an SSN or ITIN

If the responsible party doesn't have a U.S. SSN or ITIN, you can't use the online tool. Instead, file Form SS-4 by fax or mail. Fax is faster than mail. This is the standard route for partnerships with foreign responsible parties, and it takes longer than the instant online result, so plan ahead.

Every EIN application requires a "responsible party" — the person who ultimately controls or manages the entity. For a limited partnership, that's naturally a general partner, since general partners are the ones with management authority. Limited partners, being passive, generally aren't the responsible party.

What the IRS expects

• The responsible party must be a real person (not another entity) in most cases, with their own SSN or ITIN.
• The information has to be accurate — the IRS uses the responsible party to know who's accountable for the entity's federal tax matters.
• If the responsible party changes later (for example, a general partner leaves), the IRS asks you to update it using Form 8822-B.

Choosing the responsible party is usually obvious in an LP: it's the general partner running the show. Where an entity like an LLC serves as the general partner, the responsible party is typically an individual who controls that managing entity.

A few recurring errors turn a ten-minute task into a multi-week fix.

The mistakes that cause the most trouble

• Applying before the certificate is approved. This risks a name mismatch. Wait for the approved Certificate of Limited Partnership, then apply with the exact legal name.
• Choosing the wrong entity type. Selecting LLC or corporation instead of partnership sets up the wrong kind of tax account. An LP is a partnership filer; choose partnership.
• Paying a third party for an EIN. The EIN is free from the IRS. Services that charge for "EIN filing" are charging for something you can do yourself in minutes at no cost.
• Losing the confirmation letter. Save the CP 575 confirmation immediately — banks and lenders often ask for it, and getting a replacement (Form 147C) is more hassle than saving the original.
• Getting more than one EIN. A partnership needs exactly one EIN. Accidentally applying twice creates duplicate accounts that have to be cleaned up with the IRS.

Done right, the EIN is one of the smoothest steps in setting up a Colorado LP: free, instant online for eligible applicants, and permanent. Get the name and entity type right, save the confirmation, and move on to opening the bank account.