As Tax Day 2020 approaches, some self-employed individuals might need a Tax ID number. You can find out if you need one by taking a six-question IRS survey. A Tax ID number, also known as an EIN number, is an ID number issued by the IRS to identify small businesses for tax purposes. To get a Tax ID number, you can speak with your accountant or bank, call the IRS directly, fill out a form and mail it to the IRS, or apply online. See Business Insider's picks for the best tax software » Your Tax ID Number — sometimes also referred to as a Federal Tax Identification Number, a 95 Number, or EIN Number — is a nine-digit number issued by the IRS to be used by self-employed individuals for certain tax or business purposes. If you're not sure if you already have one, you can call the IRS Business & Specialty Tax Line (800-829-4933), check with the institution that you think may have issued one for you (like your bank, for example), or take a look at your most recent tax return.See the rest of the story at Business InsiderNOW WATCH: Why electric planes haven't taken off yetSee Also:I had the money to pay my tax bill in April, but I'm waiting until the July 15 deadline for 2 main reasonsThe vast majority of Americans actually qualify for free tax filing.