Michigan Child Support Calculator & Guide (2026)

At a glance

Model	Income shares on combined net income, under the Michigan Child Support Formula (MCL 552.605 makes it presumptive)
Current formula	2025 MCSF manual and January 2025 supplement, effective January 1, 2025
Parenting time	Parental time offset from the first overnight, using each parent's overnights raised to the 2.5 power
Low income	Low Income Threshold of $1,255 a month net; at or below it, base support is 10% of that parent's income
Support ends	Age 18; up to 19 years and 6 months for a full-time high school student living with the recipient
Modification threshold	A change of more than 10% of the current order or $50 a month, whichever is greater, after a Friend of the Court review
Who handles it	County Friend of the Court offices, the Prosecuting Attorney, and the MDHHS Office of Child Support

How the Michigan Child Support Formula works

The formula works on net income, and the manual warns that its net income is not the same as take-home pay. You start from all income, including wages, overtime, bonuses and self-employment earnings, then subtract actual income taxes and FICA, mandatory union dues and retirement contributions, court-ordered life insurance for the children, the parent's own share of health premiums, and spousal support paid to someone outside the case. Income can be imputed to a parent who has the ability to earn more.

The two net incomes are added into a monthly family income and fed into the General Care Equation: a base amount from the supplement's General Care Support Table, plus a marginal percentage of any income above that table row, multiplied by the parent's percentage share of family income. Each parent gets their own base support figure, rounded to the whole dollar.

Medical support and child care are separate pieces that are added later, and the parental time offset is applied to base support in every case where the overnights can be determined. A court may deviate only if it states on the record why the formula would be unjust or inappropriate, what the formula amount was, and how the order departs from it.

Worked example: Michigan

Parent A has $4,500 a month of net income under the formula and Parent B has $3,000, so the monthly family income is $7,500. Both are above the $1,255 Low Income Threshold, so the General Care Equation applies to both.
For two children, the highest table row not above $7,500 starts at $7,198.27 with $2,095.42 of base support plus 20.20% of the income over that row. That puts the family's base support at about $2,156 a month.
Parent A earns 60% of the family income, so Parent A's base support obligation is $1,294 and Parent B's is $863. Those are the same figures the supplement's two-children schedule lists for incomes of 4,500 and 3,000.
If Parent A had no regular overnights, Parent A would pay the full $1,294 a month in base support, about $15,528 a year, before ordinary medical, health premiums and child care are added.

This is an estimate, not legal advice. Figures are rounded to the dollar and leave out the insurance, childcare, and other adjustments your case may have. Try your own numbers in CoreParent's calculator, then confirm with the state's official calculator.

The parental time offset: no threshold, no cliff

Michigan's offset raises each parent's annual overnights to the 2.5 power and uses those weights to balance the two base support obligations. The supplement explains the design: no reduction when a parent has no time, small reductions for occasional time, growing reductions as time increases, and no payment at all when time and incomes are both equal. Every order must state whether it includes the offset and how many overnights were used.

In the example, if Parent A has the children 128 nights a year and Parent B has 237, Parent A's payment drops from $1,294 to about $913 a month. With exactly equal time, the higher-earning Parent A still pays about $216, because the incomes are not equal. Overnights actually exercised count, including extra nights by agreement; if practice drifts at least 21 overnights from the number in the order, either parent can move to modify.

Medical support, health premiums and child care

Orders usually set an annual ordinary medical amount that the recipient is presumed to spend: $200 for one child, $400 for two, up to $1,000 for five or more under the 2025 supplement. The payer's share is built into the monthly payment, and uninsured costs above that amount are split by the medical expense percentage in the order. The court must name one parent to carry coverage that is accessible and costs no more than 6% of that parent's gross income, and the children's portion of the premium is shared by income after the offset.

Child care needed to work, look for work or attend school is split by income share after subsidies and tax credits are subtracted. The formula presumes child care continues until the end of the month the child turns 13.

The Low Income Threshold

The 2025 supplement sets the Low Income Threshold at $1,255 a month, the 2024 federal poverty guideline for one person. A parent at or below it owes 10% of their net income as base support, and their income is left out of the family income used for the other parent. Just above the threshold, a transition equation caps support at 10% of $1,255 plus a percentage of the income above it (55% for two children) whenever that is lower than the General Care result.

Children from other relationships

A parent supporting other minor children first deducts the premium cost of covering them, then multiplies the remaining net income by an adjustment multiplier: 83% for one other child, 75% for two, 68% for three, 64% for four and 60% for five or more. Support for children-in-common is figured on all of them together, so siblings in separate cases get even amounts.

When support ends and how it changes

Support normally runs to age 18. A court may extend it while the child regularly attends high school full time with a reasonable expectation of graduating and lives full time with the recipient, but never past 19 years and 6 months, and the order must name the month it ends.

Either party can ask the Friend of the Court for a review, though the office does not have to act on more than one request from the same party every 36 months unless there is a substantial change, such as a parent's income changing by 75% or more. If the new amount differs from the order by more than 10% or $50, whichever is greater, the office must petition the court. Each payment becomes a judgment when due and can be changed only back to the date the other side got notice of the petition.

Collection, arrears and the surcharge

The MDHHS Office of Child Support opens cases and refers them; the county Prosecuting Attorney establishes paternity and orders; the Friend of the Court enforces and modifies them, and payments go through the Michigan State Disbursement Unit. Under the arrearage guideline, past-due support is usually repaid at 2% of the balance a month, at least $50 and no more than half the current support. If a court finds a willful failure to pay, it may order a semiannual surcharge on the past-due amount.

Documents you will need

Pay Stubs, last 2-3 months
W-2 Forms, last 2 years
Federal Tax Return, most recent year
Health Insurance Premium Statement
Childcare Receipts / Provider Statement
Existing Support Order (if applicable)
Schedule C (Self-Employment Income)
Business Bank Statements, 3 months
Profit & Loss Statement

Michigan child support FAQ

Is there an official Michigan child support calculator?

Yes. The MDHHS Office of Child Support runs the free MiChildSupport Calculator, which applies the Michigan Child Support Formula. Its result is an estimate, not a Friend of the Court recommendation or an order.

How is child support calculated in Michigan?

Each parent's net income is combined into a family income, the General Care Equation gives each parent a base support obligation by income share, the parental time offset adjusts it for overnights, and medical support, premiums and child care are added.

How much is child support for 2 kids in Michigan?

With $7,500 of monthly family net income and a 60% income share, a parent's base support for two children is $1,294 before the offset. With 128 overnights a year it falls to about $913, before medical and child care.

Does 50/50 custody mean no child support in Michigan?

Only if incomes are also equal. With equal overnights the higher earner still pays part of the difference; in our 60/40 example that is about $216 a month.

When does child support end in Michigan?

At 18, unless the child is attending high school full time, is expected to graduate and lives with the recipient. Then support can continue, but not past 19 and a half.

Next steps

Run your estimate in CoreParent's child support calculator and keep your assumptions next to your parenting plan.
Custody schedules that change the overnight count: every other weekend, 2-2-5-5 schedule, week on, week off.
Find a Michigan family law attorney in our directory.
States with a similar model: Minnesota, Georgia.
How custody is decided state by state: custody by state.

Sources

Verified against these official sources in October 2026:

Child support in every other state

All states

This is general educational information, not legal advice, and official figures change. Last verified: October 2026. Consult a licensed family-law attorney in Michigan.

Michigan child support: the formula, the parental time offset, and a worked example