What Is a Taxpayer Identification Number (TIN)? Everything You Need To Know

Ever tried filing taxes, opening a U.S. bank account, or applying for a loan and hit a wall because you don’t have a Social Security Number? That’s where a taxpayer identification number (or TIN) can save the day.

Whether you’re an international student, a non-citizen earning money in the U.S. or filing taxes for a dependent who doesn’t qualify for an SSN, this guide will break it all down. We’ll cover what a TIN actually is, who needs one and how to get one — without the confusing government-speak.

What Is a Taxpayer Identification Number?

A taxpayer identification number (TIN) is a number used by the IRS to identify individuals and entities in order to track them for tax purposes. A TIN is an umbrella term for different types.

What are the different types of TINs?

• Social Security Number: Most people are familiar with their Social Security Number (SSN). It is a nine-digit number issued by the Social Security Administration. It is issued to U.S. citizens and permanent residents. 
• Individual Taxpayer Identification Number (ITIN): An ITIN Is another type of taxpayer identification number. It’s issued by the IRS. An ITIN is issued to individuals who aren’t eligible to receive a SSN. This number is issued to certain dependents and nonresident aliens.
• Employer Identification Number (EIN): Businesses, trusts and estates are issued this number. 
• Adoption Tax Identification Number (ATIN): When a SSN isn’t available, an ATIN is issued as a temporary identification number for children being adopted in the United States. 

For most people reading this article, the ITIN is the star of the show. It’s what you’ll likely need if you live in or earn income from the U.S. but can’t get a Social Security Number.

What Is an ITIN?

An ITIN (Individual Taxpayer Identification Number) is a 9-digit number the IRS gives to people who need to file taxes but aren’t eligible for an SSN. It’s basically a tax ID just for individuals who don’t qualify for the traditional U.S. tax system routes.

ITINs always start with the number 9 and look like this: 9XX-XX-XXXX

Here’s the key thing: having an ITIN doesn’t mean you’re allowed to work in the U.S. or get Social Security benefits. It’s strictly for taxes. But that doesn’t make it any less important.

Who Actually Needs an ITIN?

If you’re wondering whether you need an ITIN, here’s a simple breakdown. You likely do if:

• You’re a nonresident or resident alien and need to file a U.S. tax return
• You’re the spouse or dependent of a U.S. citizen or resident but don’t qualify for an SSN
• You’re an international student or professor earning income in the U.S.
• You’re receiving U.S.-based income (like rental income, freelance payments or investment returns)

Real-Life Example: Let’s say you’re living abroad but doing freelance work for a U.S.-based company. Even if you never set foot in the U.S., the IRS still wants you to report and pay taxes on that income. An ITIN lets you do that.

What You Can (and Can’t) Do With an ITIN

Let’s get real — there’s a lot of confusion out there about what an ITIN actually lets you do. So here’s a clear split of the benefits and limitations:

What You Can Do With an ITIN:

• File a federal tax return (and stay in good standing with the IRS)
• Claim certain tax credits, like the Child Tax Credit (if you meet the rules)
• Open a bank account at some U.S. financial institutions
• Get a mortgage or loan, depending on the lender
• In some states, you can even use an ITIN to get a driver’s license

What You Can’t Do With an ITIN:

• You can’t legally work in the U.S.
• You won’t get Social Security or unemployment benefits
• It doesn’t give you immigration status or a path to citizenship

The bottom line: An ITIN isn’t a free pass to everything, but it’s super helpful for staying tax-compliant and building a financial footprint.

Quick Look: TIN vs. SSN vs. EIN

Still a little confused by all these numbers? Here’s a handy table that spells out the differences:

How To Get an ITIN in 3 Steps

Getting an ITIN is easier than it sounds, especially if you follow the right steps from the start.

1. Fill Out Form W-7

This is the official application form for an ITIN. You’ll include basic info about yourself and why you need the number.

You can find it here: Form W-7 on IRS.gov

2. Gather Your Documents

You’ll need to prove your identity and foreign status. Usually, that means submitting:

• A valid passport, or
• A combination of two other official documents (like a visa, birth certificate or foreign national ID)

3. Submit Everything to the IRS

You’ve got three options:

• Mail it directly to the IRS
• Visit an IRS Taxpayer Assistance Center (TAC) (you’ll need an appointment)
• Use a Certifying Acceptance Agent (CAA) near you — they’re trained and approved to verify documents and help you submit

Tip: If you’re applying during tax season (Jan-April), start early. ITIN approvals can take several weeks.

Renewing an Expired ITIN? Here’s What To Know

Yep, ITINs can expire — either because you haven’t used them in a few years or because the IRS phased out certain number series.

Your ITIN may need renewal if:

• You haven’t used it on a tax return in the last 3 years
• It has middle digits like 70-88, 90-92 or 94-99 (these were part of the IRS’s phased-out numbers)

To renew:

• Fill out a new Form W-7 and check the renewal box
• Send in updated identity documents
• You don’t need to include a tax return unless the IRS says otherwise

Why You Shouldn’t Ignore Getting a TIN

Still on the fence? Here’s what could happen if you skip out on getting a taxpayer identification number:

• Your tax return might get rejected or delayed
• You could miss out on refunds or tax credits you deserve
• You’ll be non-compliant with IRS rules — which isn’t fun if you ever want to apply for a visa, loan or credit card later

Bottom line: if you earn income in the U.S. or need to file taxes here, having a TIN (usually an ITIN) is a must.

What Happens If You File Without an ITIN?

Trying to file a federal tax return without a Social Security number or an ITIN can cause serious setbacks. The IRS won’t process your return, which means any refund you’re owed will be delayed–or denied altogether. You also risk losing out on refundable tax credits, like the Child Tax Credit, that require a valid taxpayer identification number.

Beyond tax implications, there could be longer-term consequences. If you ever apply for legal residency or certain immigration benefits, the government may ask for proof that you’ve been complying with tax laws. Filing without an ITIN means you won’t have the documentation to show it.

Where To Get Help With the Process

Not sure where to start? Here are a few places to turn to for help:

• IRS Website: The IRS has detailed ITIN instructions online
• Certifying Acceptance Agents: These are IRS-approved professionals who can walk you through the process and verify your documents
• Low-Income Taxpayer Clinics: Many nonprofits offer free assistance if you qualify

Get Your TIN Sooner, Not Later

If you’re living or earning money in the U.S. but don’t have a Social Security Number, a taxpayer identification number is how you stay on the IRS’s good side and avoid tax headaches down the road.

• It helps you file taxes
• You can use it to open financial accounts
• It may even help you get credit or qualify for certain benefits

So don’t put it off. Whether you’re applying for the first time or renewing an old ITIN, take that next step now. Still unsure? A quick chat with a tax pro or CAA could make the process way easier.

Information is accurate as of April 23, 2025.

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