Montana Child Support Calculator (2026)

Estimate your child support payments in Montana using our free calculator based on the official MT Guidelines (Mont. Code Ann. § 40-4-204). Enter your income details below to get an instant estimate.

Montana Child Support Calculator

Based on Montana's 2024 MT Guidelines (Mont. Code Ann. § 40-4-204)

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This is an estimate only. See our full disclaimer.

Key Facts: Child Support in Montana

  • Montana uses the Melson Formula, which ensures each parent retains a self-support allowance of $1,200 per month before calculating child support.
  • The primary support need per child is set at $350 per month under Montana guidelines.
  • A 20% standard of living adjustment (SOLA) is applied to remaining income after basic needs are met.
  • Montana bases calculations on gross income from all sources.
  • The Melson Formula provides a three-tier approach: parent self-support, child basic needs, and standard of living sharing.

Source: MT Guidelines (Mont. Code Ann. § 40-4-204) • Last verified: 2026-05-30

How Much Is Child Support in Montana?

If you make $60,000 a year in Montana, child support for 1 child is estimated at $950 per month ($11,400 per year) based on the MT Guidelines (Mont. Code Ann. § 40-4-204). This is calculated after subtracting the self-support allowance and applying the standard of living adjustment.

If you make $1,000 a week ($52,000/year) in Montana, child support for 1 child is approximately $820/month.

Montana Child Support Estimates by Income (2026)

Annual Income 1 Child 2 Children 3 Children
$40,000/yr $631/mo $834/mo $1,038/mo
$50,000/yr $788/mo $983/mo $1,177/mo
$60,000/yr $950/mo $1,140/mo $1,330/mo
$70,000/yr $1,114/mo $1,301/mo $1,488/mo
$80,000/yr $1,278/mo $1,464/mo $1,649/mo
$100,000/yr $1,609/mo $1,792/mo $1,975/mo
$120,000/yr $1,941/mo $2,122/mo $2,303/mo

Based on the Melson Formula with standard assumptions. Actual amounts vary based on individual circumstances. Compare all states →

How Child Support Is Calculated in Montana

Montana uses the Melson Formula model to calculate child support obligations. This model first ensures each parent retains enough income for their own basic needs (self-support allowance), then calculates the child's primary support need, and finally applies a standard of living adjustment.

Factors That Affect Child Support in Montana

Both parents' gross monthly incomes
Number of children requiring support
Self-support allowance for each parent
Primary support need per child
Health insurance costs for the children
Work-related child care expenses
Standard of living adjustment on remaining income
Parenting time arrangement

Important Notes for Montana

  • Montana uses the Melson Formula model, which first ensures each parent can meet their own basic needs before calculating child support.
  • The Melson Formula calculates a primary support need for each child, then allocates costs between parents based on their share of combined income.
  • A standard of living adjustment (SOLA) of 20% is applied to remaining income after basic needs are met, allowing children to benefit from higher parental income.

Example Child Support Calculation in Montana

Scenario: Parent A earns $5,000/month, Parent B earns $3,000/month, 2 children.

Step 1: Combined monthly income: $5,000 + $3,000 = $8,000

Step 2: Parent A's income share: $5,000 / $8,000 = 62.5%

Step 3: Look up basic obligation from the guidelines schedule for $8,000 combined income and 2 children.

Step 4: Multiply the basic obligation by Parent A's share (62.5%) to determine their payment.

Note: Additional adjustments for health insurance, child care, and parenting time may apply.

Frequently Asked Questions About Montana Child Support

How is child support calculated in Montana?
Montana uses the Melson Formula, a three-step model. First, each parent's self-support allowance ($1,200/month) is subtracted from their gross income. Second, the primary support need for each child ($350/month) is allocated between parents based on their income shares. Third, a 20% standard of living adjustment is applied to any remaining income to allow children to share in their parents' higher standard of living.
What is the Melson Formula used in Montana?
The Melson Formula is a child support calculation method that prioritizes three levels of need: the parent's self-support, the child's basic needs, and a standard of living adjustment. Montana adopted this approach to ensure parents can meet their own basic living expenses while still adequately supporting their children.
What income is used for Montana child support calculations?
Montana uses gross income from all sources, including wages, salaries, bonuses, commissions, self-employment income, rental income, and investment income. The court may impute income to a parent who is voluntarily unemployed or underemployed.
Can Montana child support be modified?
Yes, Montana child support orders can be modified if there is a significant change in circumstances, such as a substantial change in either parent's income, changes in the child's needs, or changes in parenting time. Either parent may request a review through the court or the Child Support Enforcement Division.
How long does child support last in Montana?
In Montana, child support generally continues until the child turns 18, or 19 if the child is still in high school. Support may continue beyond that for a child with a disability. Parents may also agree to support through college, but the court generally cannot order it beyond the age of majority.

About This Calculator

This calculator uses the official MT Guidelines (Mont. Code Ann. § 40-4-204) (2024 guidelines) to estimate child support in Montana. Calculations were last verified against the official source on 2026-05-30.

Disclaimer: This calculator provides estimates only and does not constitute legal advice. Actual child support amounts are determined by Montana courts and may differ based on factors not included here. For legal advice, consult a Montana family law attorney.

Our methodology: Based on the Melson Formula model as defined in the MT Guidelines (Mont. Code Ann. § 40-4-204). Updated for 2026.

Child Support Calculators for Other States

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