How to Verify a Tax ID

As an individual, your trusty Social Security number most likely serves as the most accessible, easiest to remember form of taxpayer identification, but the Internal Revenue Service offers a few ID alternatives to your SSN, depending on your tax situation. While your Social Security number is, of course, issued by the Social Security Administration, the IRS issues these alternative ID numbers, which you'll need to provide when filing your tax returns – so if you want that refund, and you use a taxpayer ID number, you'd better be sure you've got that number right. Fortunately, you've got a few options to validate your tax ID.

For the majority of American taxpayers, taxpayer identification numbers (also known as your TIN) come in two different varieties: an Employer Identification Number (EIN) or an Individual Taxpayer Identification Number (ITIN). Here's how they break down:

• An EIN, sometimes called a federal tax identification number, identifies a business entity. Less commonly, it is also used by estates and trusts which have income reported on Form 1041, U.S. Income Tax Return for Estates and Trusts.
• An ITIN is used as an alternative to a Social Security number for certain nonresident aliens and resident aliens, as well as their spouses and dependents who are not able to get Social Security numbers. Unlike an SSN, an ITIN is strictly used for tax processing purposes.

Those who need an ITIN must complete Form W-7, which is very aptly titled, "IRS Application for Individual Taxpayer Identification Number."

Whether it be your SSN, EIN or ITIN, the IRS requires that you provide a taxpayer ID number when filing your tax returns, claiming exemptions or claiming treaty benefits.

As a business, you'll find your Employer Identification Number on the original notice issued by the IRS when you initially received your EIN; it's also present on your previous years' tax returns. Employees can find their employer's EIN in Box B of their W-2 forms. In either case, you're looking for a nine-digit number with a dash after the second digit.

To verify an Employer Identification Number, the IRS recommends calling their Business and Specialty Tax Line at 800-829-4933. Here, you can ensure that the EIN you have on-hand is legit or you can ask for an EIN you're seeking, so long as you can provide identifying information that shows you are someone who is authorized to receive the EIN, such as a partner, corporate officer, trustee or executor. This phone line is open Monday through Friday from 7:00 a.m. to 7:00 p.m., based on the caller's own local time.

Read More: How to Find a Payer's Federal Identification Number

If you're looking to validate your tax ID on the ITIN end, you won't have to deal with the IRS' famously long call hold times. In this case, the IRS offers a free tool, known as the On-Line Taxpayer Identification Matching Program. You can use this online tool to verify up to 25 name and TIN combinations and receive immediate results. You can make up to 999 requests per day or use bulk TIN matching to verify up to 100,000 name and TIN combos. (In that case, it takes up to 24 hours to receive the results).

To use the TIN matching tool, you'll first need to sign up for IRS e-services – you just need to come up with a username, password and PIN. Once you're registered, select "TIN Matching" from the IRS' list of e-services, available at IRS.gov/e-services.