it depends; your ex claimed the child, but If there is a court order and say it says yopu are supposed to claim the kid then, you can do that but remember: There are several things you need to be aware of: The IRS doesn't care about your court order, unless it is dated before 2009. The IRS goes by it's own rules and will award the dependency to the custodial parent, if both parents try to claim the child. Your only remedy against the ex is to take her/him back to court for sanctions; You would then need to file your mended return on paper, claiming the child as appropriate. The IRS will process your return and send you your refund, in the normal time. Shortly (up to a year) thereafter, you'll receive a letter from the IRS, stating that your child was claimed on another return. It will tell you that if you made a mistake to file an amended return and if you didn't make a mistake to do nothing. The other party will get the same letter you did. If one of you doesn't file an amended return, unclaiming the child, the next letter, from the IRS, will require you to provide proof. Be sure to reply in a timely manner.
if you can claim your kid on your 2016 return then you must file amended 2016 return; to claim you r kid on your past 2016 return, Your child must live with you for more than half the year, but several exceptions apply. And youmust provide more than half of the kid?s support.
The statutes of limitations not only limits the IRS in assessing additional tax on returns filed, but it also limits the amount of time you have to claim a refund or credit due. If the three-year deadline for filing has passed, the IRS, by law, cannot issue your refund