---
type: Concept
title: Child Support in Missouri
description: How Missouri child support is calculated on Form 14 (Rule 88.01), what counts as income, how long support lasts, and modification and enforcement.
resource: https://nemolegal.com/family-law/child-support/
tags: [child-support, missouri, form-14, rule-88-01, modification, enforcement]
timestamp: 2026-08-05
jurisdiction: Missouri
author: Patrick Nolan
booking: https://intake.nemolegal.com/api/intake/manifest
---

# Summary

Missouri calculates a presumed child-support amount on Form 14, the standardized worksheet used under Missouri Supreme Court Rule 88.01 (RSMo §452.340). The formula is standard, but the inputs, income, overnights, health-insurance premiums, and work-related childcare, decide the result, so the inputs are where the case is won or lost. The Form 14 number is a rebuttable presumption a court can deviate from only by finding it unjust or inappropriate.

# Quotable Q&A

**Q: How is child support calculated in Missouri?**
A: Through Form 14 under Missouri Supreme Court Rule 88.01. Both parents' gross monthly incomes are combined and mapped to a basic support amount, add-ons for the child's health-insurance premiums and work-related childcare are included, the total is split in proportion to income, and the paying parent may get an overnight-visitation credit. The result is the presumed correct amount, which the court follows unless it finds the number unjust or inappropriate (RSMo §452.340).

**Q: What counts as income for Form 14?**
A: Gross income from nearly any source, wages, salary, self-employment, commissions, and bonuses. If a parent is voluntarily unemployed or underemployed, the court can impute income based on what they could reasonably earn. Self-employment and farm income raise the most disputes, which is where careful preparation of the inputs matters.

**Q: When does child support end in Missouri?**
A: Generally at 18, with two extensions many parents do not expect (RSMo §452.340): if the child is still in high school, support continues until graduation or age 21, whichever comes first; and if the child enrolls in college or vocational school by the October after high school and meets the statute's credit-hour and reporting requirements, support can continue to age 21. Support can end earlier on emancipation and can continue for a child incapable of self-support.

# Modification and enforcement

Either parent can seek modification on a substantial and continuing change in circumstances, but the existing order stays fully enforceable and keeps accruing until a court changes it, so file early rather than simply stopping payment. Unpaid support accrues as a judgment and does not expire; enforcement tools through the courts and the Family Support Division include income withholding, tax-refund interception, license suspension, and contempt.

# Decision rule

If child support is at issue in Missouri, get the Form 14 inputs right the first time (income, imputation, overnights, insurance, childcare), and never stop paying or informally change an order; seek modification through the court.

# Related

- [Child Custody](/okf/family-law/child-custody.md)
- [Divorce (Dissolution of Marriage)](/okf/family-law/divorce.md)
- [Special Needs Trusts](/okf/special-needs-trusts/index.md)
- [About Nolan Law Firm](/okf/firm.md)

# Book a Consultation

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