A Closer Look at State Child Support Guidelines

Child Support in Shared Custody Arrangements

Many states have laws that presume it's best if parents have joint or shared legal custody of their children after a divorce, unless there's some reason not to. But what happens if the parents share joint physical, as well as legal, custody? More to the point: how does child support work if each parent has physical custody an equal amount of time, as is often the case in a joint physical custody arrangement?

“When parents have joint physical custody, shared custody, or split custody of a child, the determination of child support is complicated and may not fit the formula,” according to Michigan's 2004 Child Support Formula Manual.

Michigan's formula is indeed complicated, and it is indeed a formula! Are you ready? Take the number of overnights the children will annually spend with Parent A squared times Parent B's base support obligation and subtract the number of overnights the children will annually spend with Parent B squared times Parent A's base support obligation and divide the whole thing by the number of overnights the children will annually spend with Parent A squared plus the number of overnights the children will annually spend with Parent B squared. That will give you your base support.

The good news is that this formula is only valid if the “noncustodial” parent has a minimum of 128 overnights.

Michigan also has an abatement formula for parents who are not using the preceding formula, when a noncustodial parent spends a long period of time with the child. The abatement is 50 percent of the daily expenses as prorated by the child support award.

According to the American Bar Association, 28 states include a shared parenting time offset in their child support guidelines. (For a chart of general child support criteria in every state, see the American Bar Association website.)

As we repeat again and again, every state is different. Each state has its own very unique child support guidelines; so you must investigate the guidelines in your state to know where you stand.