Many parents believe that if the children live primarily with them during the year, that they get to claim the children on taxes that year. 
However, in family law cases, the courts in Colorado do things differently than what the IRS does.
Colorado law states that the Court must allocate who claims the children’s tax dependency exemptions based on each parent’s proportionate income. Under Colorado law, the tax exemptions are not based on which parent the children live with most of the time. See C.R.S. 14-10-115(12).
Here’s an example: the children live primarily with Mom and spend summers with Dad. Dad pays child support. Mom and Dad make the same amount of money. In this scenario, then the Court would likely order that Mom claims the kids one year, Dad the next, Mom the next after that, and so on. However, this is provided that Dad is current on his child support obligation. If he is not, then Mom can claim the kids instead of Dad.
Here’s another example: a child lives equally with both parents. Mom earns $75,000 a year, and Dad earns $25,000 a year. Mom pays Dad child support. The combined income for both parents is $100,000. Mom’s proportion of the incomes is that she earns 75% of the parents combined incomes. If Mom is current on her child support obligation to Dad, Mom claims the child three years in a row, and Dad claims the child one year, Mom the next three years, Dad one year, and so on.
See an attorney to come up with some creative ideas as to how to allocate tax exemptions that complies with Colorado law.
Also keep this in mind: child support, as well as who claims the tax exemptions, may be modified based on a substantial change in circumstances.