Only one parent may claim a child in a divorce situation

In general, if you want to claim your child as a dependent, you must be the custodial parent. A custodial parent is the parent with whom the child lived with for the greater number of nights during the year. If the child was with each parent for an equal number of nights, the custodial parent is the parent with the higher adjusted gross income, if the parents can’t agree to who claims the child.

If you are the noncustodial parent, the custodial parent must sign a written declaration that he or she will not claim the child as a dependent; you must attach this written declaration to your tax return. Without the proper declaration, the IRS will deny your dependency exemption. To release the dependency exemption, the custodial parent may use either Form 8332, Release/Revocation of Release of Claim to Exemption for Child by Custodial Parent, or a similar statement containing the same information as the form.

If the divorce decree or separation agreement went into effect after 1984 and before 2009, the noncustodial parent can attach certain pages from the divorce decree or agreement instead of Form 8332, provided that these pages are substantially similar to Form 8332. The decree or agreement must state all three of the following:

The noncustodial parent can claim the child as a dependent without regard to any condition (such as payment of support).
The other parent will not claim the child as a dependent.
The years for which the claim is released.

The noncustodial parent must attach all of the following pages from the decree or agreement.

Cover page (include the other parent’s SSN on that page).
The pages that include all of the information identified in 1 - 3 above.
Signature page with the other parent’s signature and date of agreement.