Maybe ... but you will likely need your ex's agreement.
I have assumed that none of your children lived with you for more than 6 months of the year, but did live with your ex for more than 6 months of the year. Your ex is the custodial parent and we she otherwise qualifies for the Head of Household filing status.
You may claim one or more of the children as a depedent providing your ex agrees on IRS Form 8332. (The form is easily obtained from the IRS website). You submit a signed copy of this form with your income tax return for each dependent child.
You will be able to claim the personal exemption for the child named on Form 8332. In addition, will be able to claim the child tax credit for the same dependent so long as you and your child satisfy the qualifying requirements.
As the non-custodial parent paying for the support of your child, it is possible to claim some or all of your children as dependents on your tax return. Your ex spouse will need to complete and sign Form 8332 and provide it to you. This form releases her/his right to claim the dependent on their own tax return, and releases it to you. You will need to attach this form to your tax return each time you claim the dependent.
Any individual seeking legal advice for their own situation should retain their own legal counsel as this response provides information that is general in nature and not specific to any person's unique situation. Circular 230 Disclaimer - Advice given in this response cannot be used to eliminate penalties with the IRS or any other governmental agency.
