Why do I pay child support if we have joint custody and we both work?

I know two people that separated and share custody and both have jobs yet he pays child support? How does this work?

This is a great question and a question that many parents ask. I will answer it using the law that applies in the jurisdiction where I practice law (Utah).

Some believe that if child custody is equally awarded to/shared between the parents, so that the children spend as many overnights with one parent as they do with the other, that neither parent pays the other child support. This is not true.

In a nutshell, the amount of child support a parent who shares joint equal physical custody of their children is not determined by the number of overnights the children have with that parent but by income.

If one of the two joint equal custodial parents earns more than the other, that parent will end up paying some child support. Here is how it works:

Add the father’s and mother’s gross monthly income to determine the combined gross monthly income of the parents.

Then find out what the parents’ combined child support obligation is using the child support tables in the Utah Code.

So if Mom and Dad have two kids and earn a combined total of $7,100 per month, their combined child support obligation for two kids would be $1,413 per month.

Next, you determine what percentage of the combined gross monthly income each parent has earned. So let’s say that Mom earns 20% of the combined parental income and Dad earns 80%. That would mean Mom earns a gross monthly income $1,420 per month and Dad earns a gross monthly income of $5,680.

If you stopped here and awarded child support on a sole custody basis, and if Dad were the noncustodial parent (Dad almost always is when there isn’t joint custody, but I digress) the noncustodial parent would pay 80% of the combined parental child support obligation of $1,413 per month. 80% of $1,413 is $1,130.

Now with joint equal custody, you take an additional step before your child support calculations are complete. Specifically, you account for the fact that each parent has the children in his/her custody an equal number of overnights, which means that, unlike a noncustodial parent situation, the children are spending more time in Dad’s care and custody, meaning they eat more of his food and use more of his water and he has to provide more in the way of heating and bedding, etc. The financial burdens of parenthood do not fall primarily on one parent’s shoulders or the other, and so the amount of money that Dad pays in child support becomes essentially only a function of the disparities in the parents’ respective incomes and not so much a function of how many overnights the children spend with each parent. This is why, if the Dad in our hypothetical scenario had joint equal custody his child support obligation of between $411 and $437, instead of a noncustodial child support obligation of $1,130.

Utah Office of Recovery Services Child Support Calculator – (

Utah Code Chapter 78B-12. Utah Child Support Act

Utah Family Law, LC | | 801-466-9277

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