A Quick Guide to Your W-2 Tax Form

If you're an American who worked as an employee in 2017, then you should have your Form W-2 by now. Although it's smaller than a standard piece of paper, it has vital information you need in order to do your taxes right.

Some of the information on your W-2 tax form is obvious. But there are also some secrets hidden in plain view on the form. Below, we'll give you a box-by-box guide to Form W-2 so you'll understand everything on it.

IRS Form W-2
IRS Form W-2

Image source: Internal Revenue Service.

Boxes a-f: Personal information

Along the left side, you'll see your Social Security number and your employer's tax ID number. Your employer's name and address is given, along with any internal control number your employer assigns to you. You'll also want to make sure that your complete name and address are correct to avoid any problems.

Box 1: Wages, tips, other compensation

Here, you'll find your net federal taxable income to report on your tax return, after adjusting for certain income exclusions and deductions. For instance, if you have money taken out of your pay for health insurance costs or 401(k) contributions, this number will already reflect the reduction for those items. Usually, you can copy this number directly onto the line for wages on your return.

Box 2: Federal income tax withheld

You'll find the total amount withheld from your pay by your employer for federal income taxes in Box 2. This number goes into the section in which you calculate your final refund or amount owed, giving you credit for the money withheld. Whether you get a refund or owe money depends on whether this number is higher or lower than your total tax due on your return.

Box 3: Social Security wages

The number in Box 3 almost always matches your regular wages in Box 1, but there are a few situations in which your wages for Social Security purposes will be different. Some deductions from income, such as retirement plan contributions, aren't deductible for Social Security payroll tax purposes, and so this number can be higher than the corresponding Box 1 number. Conversely, if you earned more in 2017 than the maximum Social Security wage base of $127,200, then this number will reflect that maximum rather than your actual wages.

Box 4: Social Security tax withheld

Box 4 takes Social Security wages and multiplies it by the payroll tax rate of 6.2% to give you your final withholding. In some cases in which you work more than one job, you might need this number to calculate a refund, but most people don't have to worry about that situation.