W-2s are official tax forms that companies provide to their employees summarizing their wages, taxes withheld, etc. This information is reported using a standard IRS template containing 20 boxes. The following is what each of the boxes represents.
Boxes 1, 7, and 8
This is your gross earnings (wages, tips) - how much money you made before taxes were taken out. If you work for an employer where tips are received, then Boxes 7 and 8 will show how much was earned in tips only.
Boxes 2, 4, and 6
These are the amounts that have been withheld for federal taxes, Social Security tax, and Medicare tax.
Boxes 3 and 5
These are your earnings which are subject to Social Security and Medicare tax. For most people, this value represents your gross earnings minus contributions to a tax-sheltered retirement account like a 401(k).
This box is no longer applicable and may be ignored.
Any dependent care benefits paid by your employer will be shown here.
Deferred compensation income from your employer from a non-qualified plan.
Income or contributions that may alter your taxable income. For example, money saved to a 401(k) retirement plan would be reported here and reduce your taxable earnings. However, if you received a fringe benefit such as a company car or group-term life insurance over $50,000, then this would be considered taxable income and increase your taxable earnings.
Identifies if you worked as a statutory employee not subject to federal income tax withholding, participated in an employer-sponsored retirement plan, or received sick pay through another source (such as an insurance policy).
A catch-all for other tax information. These may include union dues, disability insurance taxes, etc.
Similar to your federal taxes, these boxes will report your wages and taxes withheld for the state and city. Check with your local state and city treasury departments to see if additional income tax returns are necessary.