Montana Child Support Calculator

Child support calculator

Simple Child Support Calculator

To calculate child support in Montana, we recommend using the Montana Child Support Guidelines. There appears to be no simpler way to estimate support payments.

The Montana Child Support Guidelines steps you through a complex calculation. You may need to work through each part carefully to get an accurate assessment. Unfortunately, the Montana scheme is complex and a simple, reliable calculator does not appear to be available.

Parenting Time Calculator for Montana

According to Montana child support guidelines, payment amounts depend on how many days a child spends with each parent.

Use this calculator to work out how much care a parent provides. Count every day when the parent is reponsible for the child(ren) for more than 12 hours.

Calculate parenting time %

Regular days
Vacation days each year*
183 days per year.
50.0% of parenting time.

* Vacation days are all days when the regular schedule does not apply.

How Child Support is Calculated in Montana


Child support payments in Montana are calculated using the income shares category method. Payments depend on the combined incomes of the parents as well as the number of children. A larger combined income or more children usually means greater payments.

The amount paid or received by an individual parent also depends on their income percentage. The higher your percentage of combined parent income, the more you pay or less you receive.

Payments are also affected by which parenting time category applies. Payments may be lower because of a "shared" (fairly equal) care arrangement.

Montanans paying the most child support have high incomes and limited parenting time. Conversely, the biggest receivers are parents who (a) work little (b) have their kids most of the time and (c) have a high earner as the other parent.

A "day" is defined as the majority of a 24-hour period in which the child is with or under the control of a parent. Unless otherwise agreed by the parents or specifically found by the court, a parenting period begins at midnight of the first day and ends at midnight of the second day.

In Montana, child support must be calculated pursuant to a complex formula set by state law. The final child support amount can deviate from the statutory formula if the parties agree or if there is good cause to do so, such as a child with special needs.

P. Mars Scott Law Offices

Montanan child support guidelines apply to the whole state, including the cities of Billings, Missoula, Great Falls and Bozeman. Variations in support payments may be made by the agreement of parents or at the discretion of a judge presiding over your case.

Payment Calculators by State

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