Michigan Child Support Calculator

Improving Advocacy in Michigan Family Law©

About the Child Support Formula


How does the State of Michigan calculate child support?


Child support is based on far fewer factors than most people (and attorneys) think. Here's how it adds up:


1. Calculate a base support figure.

Base support is how much the State of Michigan thinks your children cost monthly. Base support is based on the parents' combined incomes and the number of children. If you make a lot of money, it's presumed that you spend a lot of money on the children. If you make little money, the formula presumes you don't spend as much on the children.


To get a figure for base support, the formula adds both parents' incomes together. The child support formula says what counts as income and what doesn't.The formula also allows for certain deductions. If you have other children that aren't a part of this order, an allowance for them is deducted from your income. In cases where one party has no or little income, their income is counted differently or not counted at all.


The parents' total income is applied to a table that says what percent of that income the parents should/likely/must put towards the children.


2. Determine what percent of base support is each respective parent's responsibility.

Once the formula arrives at a base support amount, you figure out how much of base support is each party's responsibility. This is based on percentage of income. For example, if base support is $1000 per month, and you make 80% of total parental income, your percent of base support is $800 per month.


3. Adjust for parenting time.

The formula assumes that the more time you spend with the children, the more you contribute directly to their needs. So, if you have the children part of the time, and your base support is $800 per month, you will not have to pay the other parent the whole amount. You will pay a portion of it, as determined by a formula. What you pay will be adjusted downward based on the number of overnights the children spend with you. Alternatively, if you receive support and the other parent has parenting time, they won't pay you their entire base support amount. They'll pay you a percentage of it, depending on the number of overnights the children spend with the other parent.


4. Adjust for medical insurance premiums.

Does one parent provide medical insurance? If so, the other parent must contribute their share of the children's out-of-pocket medical premium cost, based on percentage of income. This will be added to or deducted from child support, depending on who provides medical insurance.


5. Adjust for child care.

Do the children attend day care? If so, the paying parent will pay the other for day care, in advance. This is, like medical insurance premiums, based on percentage of income. The parent who receives support then pays day care bills as they incur.


6. Add ordinary medical.

The formula presumes that each child incurs a certain amount of unpaid medical costs each year, for things like copays and bills that insurance doesn't cover. Band-aids and cough syrup and the like are not ordinary medical. Those things are covered by base support. Ordinary medical is unpaid medical bills. This is a fixed amount per child. This cost is payable according to precentage of income. It is added to support. Then, the person who receives support pays for ordinary medical bills as they incur during the year, until bills reach the total medical amount. After that, unpaid medical is paid according to percentage of income.


7. Total

The resulting amount is the total amount of support. Of course there are exceptions to the rules, and exceptions to the exceptions. What is discussed here is just the basics. Because of the exceptions, and the exceptions to the exceptions, and the complicated parenting time formula, most people (and attorneys) don't do manual child support calculations.