This article was co-authored by Cassandra Lenfert, CPA, CFP® and by wikiHow staff writer, Jennifer Mueller, JD. Cassandra Lenfert is a Certified Public Accountant (CPA) and a Certified Financial Planner (CFP) in Colorado. She advises clients nationwide through her tax firm, Cassandra Lenfert, CPA, LLC. With over 15 years of tax, accounting, and personal finance experience, Cassandra specializes in working with individuals and small businesses on proactive tax planning to help them keep more money to reach their goals. She received her BA in Accounting from the University of Southern Indiana in 2006.
There are 13 references cited in this article, which can be found at the bottom of the page.
This article has been fact-checked, ensuring the accuracy of any cited facts and confirming the authority of its sources.
This article has been viewed 2,551,601 times.
Every individual and business in the US has a unique tax ID number—this is how the IRS identifies each taxpayer. But what happens if you can't find one that you need? Ultimately, it depends on whether the number you're looking for is your own or someone else's. There are plenty of official documents where you can find the number you need if you just know where to look. Read on to find out where to look to get the individual TIN (Tax ID Number), SSN (Social Security Number), or business EIN (Employer Identification Number) that you need.