<prompt> Human: So my parents and I both already filed our 2017 tax returns. I marked myself as Someone else can claim me as a dependent. My parents planned to claim me, which was acceptable because they really did provide more than half my living expenses.However, I just found out my parents were not allowed to claim me because I make too much and am not a full time student Im 21 yo, for the record. Because of this, should I file an amended tax return removing that dependent status?My previously filed return has already been paid out, and Im not sure if that will affect anything.  <response>: Yes. If you cannot be claimed as a dependent because you fail the age test for qualifying child, and you fail the gross income test for qualifying relative, for example, then you should amend your filing and claim yourself.Doing this means you get to remove 4050 from your taxable income. This will reduce your tax by 4050 marginal tax bracket. Some tax deductions or credits might become available to you that you wouldnt have if you were a dependent -- such as HSA deduction, retirement savings contributions credit. So youd want to go through to see if anything else changes in your picture.Prepare a 1040X and mail it in. The already received refund ends up getting put on line 17, I think, so that they wont send that to you twice. Just the new refund amount will be sent. 