Montana Child Support Guidelines: How Support Is Calculated

In Montana, child support is not something a judge simply decides by feel. The court is required to apply the child support guidelines adopted by the Department of Public Health and Human Services (DPHHS), and the amount that formula produces is presumed to be adequate and reasonable unless a parent shows, by clear and convincing evidence, that it would be unjust or inappropriate in a particular case. That presumption is set out directly in Montana law, and it means most Montana child support amounts start - and usually end - with the guideline calculation, not a negotiation.

The basic structure of Montana's guideline formula

Montana's guidelines live in the Administrative Rules of Montana (ARM), Title 37, chapter 62, which the state's child support agency (CSSD), the District Courts, and the Office of Administrative Hearings are all required to use. The Montana model uses a structure sometimes called a "Melson-style" formula, built around three core pieces:

• A personal allowance reserved for each parent before any support is calculated.
• A primary child support allowance based on the number of children.
• A Standard of Living Adjustment (SOLA) that shares a portion of income above the basics with the children.

Rather than a single lookup-table number, the guidelines walk through several steps, described below in plain language.

Step 1: Figure out each parent's income

Montana's guidelines define "income" broadly. It is not limited to a paycheck - it can include wages, self-employment earnings, pensions, Social Security, unemployment benefits, rental income, interest, dividends, and trust income, among other sources. Both parents' income typically gets counted, since the guidelines are built around both households.

Step 2: Subtract allowable deductions

Before the guideline math produces a support figure, certain items are subtracted from income. Allowable deductions can include taxes, FICA (Social Security/Medicare withholding), court-ordered support already being paid for other children, and certain health and dependent-care costs. What is left after these deductions is used in the next step.

Step 3: Subtract each parent's personal allowance

Each parent keeps a "personal allowance" - essentially a self-support reserve - before any income is treated as available for child support. Under the guidelines, this allowance equals 1.3 times the federal poverty guideline for a one-person household, which means it changes every year as federal poverty figures are updated. Time-sensitive: as of 2026 that allowance is roughly $20,700, but because it resets annually, always confirm the current-year figure with Montana's child support guidelines rather than relying on a fixed number.

What remains after subtracting deductions and the personal allowance is called "income available for child support."

Step 4: Apply the primary child support allowance

From that available income, a primary child support allowance is set aside for the children. It is derived from the personal allowance figure - roughly 30% of it for one child, with additional percentages layered in for more children. Time-sensitive: for 2026, that works out to approximately $6,200 per year for one child, but like the personal allowance, this number moves each year with the federal poverty guideline, so it should be verified against the current guidelines rather than assumed.

Step 5: Standard of Living Adjustment (SOLA)

If there is still income left over after the steps above, Montana's guidelines apply a Standard of Living Adjustment so children share in a parent's higher income, not just the bare minimum. The SOLA percentages increase with the number of children: 14% for one child, 21% for two, 27% for three, 31% for four, and 35% for five, with the percentage continuing to rise for larger families. SOLA income can never be calculated as less than zero - if there is nothing left after the earlier deductions, there is no SOLA add-on.

Can the guideline amount be changed?

Because the guideline result is presumed correct, a parent who wants a different number carries the burden of proving, with clear and convincing evidence, that following the guideline would be unjust or inappropriate given the specific facts of the case. This is a deliberately high bar - it is not enough to simply disagree with the result. If you believe your situation involves something the standard formula doesn't capture well, that is a conversation to have with the Montana court or CSSD, supported by documentation, rather than something to resolve informally between parents.

Temporary support while a case is pending

Montana law also allows a court to issue a temporary order for support (along with related temporary orders, like injunctions) while a dissolution of marriage, legal separation, or related family law proceeding is still working its way through the system. This lets a parent seek interim support rather than waiting months for a final resolution. Temporary orders are generally superseded once the court enters a final order, so it's worth confirming with the court how a temporary figure will transition into the final calculation.

How Montana support orders connect to federal law

Montana's child support system doesn't operate in isolation - it runs on top of a federal framework that every state must follow to keep receiving federal funding for its child support program (the "Title IV-D" program). That federal law requires states to have standardized enforcement tools available, including:

• Income withholding directly from a paying parent's paycheck.
• License suspension and other administrative penalties for nonpayment.
• Liens against property to secure unpaid support.
• The ability to garnish certain federal wages and benefits to satisfy a support order, since federal law waives sovereign immunity for this purpose.

Separately, federal law requires every state to enforce (and generally not modify) a valid child support order issued by another state, which matters if one parent later moves out of Montana. This full-faith-and-credit rule works alongside Montana's adoption of the Uniform Interstate Family Support Act (UIFSA) to determine which state's order controls when parents live in different states.

What happens to child support in bankruptcy

If a paying parent files for bankruptcy, federal bankruptcy law treats child support (and spousal support) as a "domestic support obligation." These obligations cannot be discharged - wiped out - in bankruptcy, and they are paid first among unsecured claims when there isn't enough money to pay everyone. Debts from a property settlement in a divorce decree are also generally treated as non-dischargeable in a standard Chapter 7 bankruptcy case. In short: bankruptcy is not a way to escape a Montana child support obligation.

What you can do in Montana

1. Gather income documentation for both parents - pay stubs, tax returns, self-employment records, and any other income sources listed above - before a hearing or CSSD review.
2. Identify your allowable deductions, such as other court-ordered child support, taxes/FICA, and qualifying health or dependent-care costs, so they can be factored into the calculation.
3. Check the current-year personal allowance and primary child support allowance figures with Montana's guidelines or CSSD rather than relying on last year's numbers, since both adjust annually.
4. If you believe the guideline amount is unjust or inappropriate for your family's situation, prepare clear and convincing evidence to present to the court - this is a high standard, so documentation matters.
5. If support is unpaid, contact Montana's Child Support Services Division (CSSD) to learn about income withholding, license suspension, and other enforcement tools available under state and federal law.
6. If either parent moves out of state, don't assume the Montana order disappears - federal law and UIFSA generally keep the original order in force and specify which state has authority to modify it.

This article is for general information only and is not legal advice; for guidance on your specific situation, consult a licensed Montana attorney or Montana's Child Support Services Division.