The amount of social security and Medicare tax withheld from your pay appears in Boxes 4 and 6 of IRS Form W-2. There is a maximum amount of wages subject to social security tax.
The maximum amount of wages subject to the social security tax (6.2 percent) for 2016 is $118,500. There is no limit on the amount of wages subject to the Medicare tax (1.45 percent).
The maximum amount of wages subject to the social security tax (6.2 percent) for 2017 is $127,200. There is no limit on the amount of wages subject to the Medicare tax (1.45 percent).
The maximum amount of wages subject to the social security tax (6.2 percent) for 2018 is $128,400. There is no limit on the amount of wages subject to the Medicare tax (1.45 percent).