Michigan calculates child support using a formula, not a flat rate

Michigan does not set a single dollar amount for one child. Instead, the state uses the Michigan Child Support Formula, which takes the paying parent's income, the receiving parent's income, custody arrangement, and other costs (like health insurance and childcare) and produces a monthly obligation. Two parents with the same income and custody split will owe different amounts depending on whether they earn $30,000 or $80,000 per year.

The formula applies to most cases, though a judge can order a different amount if the standard calculation would be unjust or inappropriate. Understanding how the formula works helps you see why your case produces the number it does.

Key Takeaways

  • Michigan's formula multiplies combined parental income by a percentage (17% for one child) to find the base support amount, then divides it based on each parent's income share.
  • The formula includes both parents' gross income, including wages, self-employment earnings, bonuses, and some benefits, but excludes means-tested public assistance.
  • The paying parent's obligation changes if they have other children from other relationships, if they pay for health insurance or childcare, or if custody is not a standard 50/50 or primary-custody split.
  • A Michigan Friend of the Court office calculates the amount and issues a recommendation; a judge signs the final order, which can differ from the formula if circumstances warrant it.
  • The formula percentage for one child is 17% of combined parental income, but this percentage increases if there are more children.

How the Michigan formula calculates the base amount

The first step is to add both parents' gross monthly income. Gross income includes wages, salary, self-employment earnings, bonuses, commissions, rental income, and some government benefits. It does not include means-tested assistance like food assistance or Medicaid.

Multiply the combined income by 17% (the percentage for one child). This is the base child support amount before adjustments. For example, if both parents earn $3,000 per month gross ($6,000 combined), the base amount is $1,020 per month.

Next, divide the base amount between the parents according to their income share. If one parent earns $4,000 and the other earns $2,000 (combined $6,000), the higher earner pays two-thirds of the base amount. The parent with primary custody or more parenting time usually receives the payment; the other parent pays it.

What gets added or subtracted from the base amount

The formula starts with the base calculation, but several costs adjust the final number. If the paying parent pays for the child's health insurance, that premium is subtracted from their obligation. If the paying parent pays for childcare so the receiving parent can work, a portion of that cost is also subtracted.

If the paying parent has other children from other relationships, the formula accounts for those obligations. The income used to calculate support for the first child is reduced by the amount already owed for other children, lowering the amount owed for the child in your case.

If custody is not a standard arrangement (one parent has primary custody, the other has parenting time), the formula adjusts. If both parents have roughly equal parenting time, the calculation changes because both parents are providing housing and food. The Friend of the Court will recalculate based on the actual custody order.

Income limits and how they affect the calculation

Michigan's formula applies to combined parental income up to a threshold that changes each year. In 2024, that threshold is approximately $163,000 per month in combined income. If both parents earn more than that combined amount, the formula still applies to income up to the threshold, but income above it is discretionary — a judge decides whether to include it.

Self-employment income is included but calculated differently. The Friend of the Court will ask for tax returns and business records to verify the actual net income from self-employment, not just gross revenue.

Who calculates the amount and how it becomes an order

The Friend of the Court office in your county calculates the recommended child support amount using the formula. They send both parents a Child Support Recommendation that shows the income figures used, the formula calculation, and the monthly amount. This recommendation is not yet an order.

Either parent can object to the recommendation in writing within 21 days. If neither parent objects, the recommendation becomes the order automatically. If one parent objects, a judge reviews the case and issues a final order, which may match the recommendation or differ from it.

The final order is signed by a judge and becomes legally binding. The paying parent must pay the amount stated in the order, usually by wage withholding (the employer deducts it from the paycheck) or by direct payment to the Friend of the Court.

How changes in income or custody affect the amount

Child support is not permanent at the amount set in the initial order. If either parent's income changes significantly, or if custody changes, either parent can ask the Friend of the Court to recalculate. A change of 10% or more in either parent's income usually triggers a recalculation.

If the paying parent loses a job or takes a lower-paying position, they can request a modification. The Friend of the Court will recalculate based on the new income. If the receiving parent's income increases substantially, that also affects the calculation because the formula uses both parents' income.

If custody changes — for example, if the child moves to live primarily with the other parent — the formula recalculates because the parent receiving support changes. The parent who was paying may now receive support, or the amount may decrease.

Frequently Asked Questions

What if one parent has no income or very low income?

The formula still applies. If a parent has no income, the Friend of the Court may impute income based on full-time minimum wage work or the parent's earning capacity. If a parent is unemployed but capable of working, the court may assign income rather than use zero. This is contested often, and a judge makes the final decision.

Does child support change if I have another child with a different partner?

Yes. The formula reduces the income used to calculate support for the first child by the amount owed for the second child. This is called a "deviation" for other children. You must have a court order for the second child for this to apply; informal support does not count.

Can the amount be different from what the formula produces?

Yes, but only if a judge finds the formula amount would be unjust or inappropriate given the circumstances. This is rare. Reasons include unusual parenting time, substantial assets, or significant special needs of the child. The judge must state in writing why the formula does not apply.

What happens if the paying parent does not pay?

The Friend of the Court enforces the order. They can pursue wage withholding, intercept tax refunds, suspend licenses, or file a contempt case. Unpaid support accrues interest and can result in jail time if willful non-payment is proven in court.

How often does the amount get reviewed?

Either parent can request a review at any time if circumstances change. The Friend of the Court also reviews cases every three years automatically in some counties. Check with your local Friend of the Court office for their review schedule and procedures.