Every year we get at least newlywed that is confused about how to file their return.  The rules are simple - your filing status is determined as of 12-31.  If you’re married on the last day of December, your filing status is Married Filing Joint/Separate.  It doesn’t matter about the previous 364 days.

If you change your last name, you need to file a SS-5 with the Social Security Administration.  Depending upon the timing, you may need to use your maiden name when filing your taxes.  It takes a bit of time for the name change to work its way through the SSA and onto the IRS computers.