The status of 'married' or 'single' on your W-2 has nothing to do with how you file your taxes, only with how taxes were withheld by your employer. Single status withholding is higher than married, which means you probably paid more taxes than you needed to. This is not a huge problem, and can get back the excess paid in a refund when you file as married. If you want to change your filing status or the number of withholdings that your employer uses to calculate taxes, you need to file a W-4 with your HR office. Even if you were only married for one day last year (say, you got married on December 31st), you still get to file as married for the entirety of the year.

The status of 'married' or 'single' on your W-2 has nothing to do with how you file your taxes, only with how taxes were withheld by your employer. Single status withholding is higher than married, which means you probably paid more taxes than you needed to. This is not a huge problem, and can get back the excess paid in a refund when you file as married. If you want to change your filing status or the number of withholdings that your employer uses to calculate taxes, you need to file a W-4 with your HR office. Even if you were only married at the tail end of the year (say, you got married on December 31st), you still get to file as married for the entirety of the year.