Start with Mo. Rev. Stat. § 452.340; Missouri Supreme Court Form 14 Directions. In Missouri, Missouri uses the Income shares (Form 14) and measures income as gross income. Missouri’s Form 14 combines adjusted gross incomes, applies a schedule of basic support, and allocates by income share. Overnight credits, extraordinary expenses, and health-care costs are built into the Form 14 calculation presumed correct. That is the question this guide answers for how child support is calculated. Support generally ends when Support generally ends at 18, or continues if the child is enrolled in secondary school, not past 21 in typical statutory scenarios. Modification: Substantial and continuing change; a 20% change in the child support amount is a common statutory threshold.
Statutory framework and guideline model
Missouri's child support system is built around Mo. Rev. Stat. § 452.340; Missouri Supreme Court Form 14 Directions. Under the income shares (form 14), Missouri’s Form 14 combines adjusted gross incomes, applies a schedule of basic support, and allocates by income share. Overnight credits, extraordinary expenses, and health-care costs are built into the Form 14 calculation presumed correct.
Federal law requires every state to maintain presumptive guidelines and to review them at least every four years (42 U.S.C. § 667). Confirm the latest Missouri schedule or worksheet before relying on any online calculator.
How child support is calculated in Missouri
- Identify each parent's guideline income using gross income as defined in Mo. Rev. Stat. § 452.340; Missouri Supreme Court Form 14 Directions and the accompanying worksheets or administrative rules.
- Apply the income shares (form 14) — whether that means a combined-income schedule, an obligor percentage table, or a Melson-style self-support reserve plus primary obligation.
- Allocate add-ons such as health insurance premiums, unreimbursed medical expenses, and work-related child care according to Missouri practice.
- Consider parenting time adjustments where the guidelines or case law authorize a credit or shared-custody formula.
- Test for deviation if a strict guideline result would be unjust or inappropriate on the record.
Online calculators can illustrate ranges, but only the controlling statute, guidelines, and court findings produce an enforceable order.
How the Missouri rule applies
Apply the Missouri authorities in order. The facts are simplified so the statute and the standard are visible.
Two parents in Missouri need a presumptive child-support figure and may have facts that justify a departure.
- Measure guideline income as gross income under Mo. Rev. Stat. § 452.340; Missouri Supreme Court Form 14 Directions.
- Apply the Income shares (Form 14): Missouri’s Form 14 combines adjusted gross incomes, applies a schedule of basic support, and allocates by income share. Overnight credits, extraordinary expenses, and health-care costs are built into the Form 14 calculation presumed correct.
- Test deviation: Rebuttal of Form 14 requires a finding that the amount is unjust or inappropriate after considering all relevant factors.
- If circumstances later change: Substantial and continuing change; a 20% change in the child support amount is a common statutory threshold.
The enforceable number is the Missouri guideline result under Mo. Rev. Stat. § 452.340; Missouri Supreme Court Form 14 Directions, plus any deviation findings. Family Support Division enforces with income withholding, intercepts, and contempt.
Deviation from the guidelines
Rebuttal of Form 14 requires a finding that the amount is unjust or inappropriate after considering all relevant factors.
When a court departs from the presumptive amount, Missouri practice generally requires findings that explain why the guideline figure is unjust or inappropriate and what amount better serves the child's needs. Those findings matter on appeal and in later modification proceedings.
Modification of child support
Substantial and continuing change; a 20% change in the child support amount is a common statutory threshold.
A parent seeking a change typically must show that circumstances after the prior order make the existing award inequitable. Common triggers include job loss, substantial income changes, a new parenting-time schedule, emancipation of a child, or extraordinary medical needs. Retroactivity and temporary relief rules are statute-specific — check Mo. Rev. Stat. § 452.340; Missouri Supreme Court Form 14 Directions and local family-division procedures.
Enforcement in Missouri
Family Support Division enforces with income withholding, intercepts, and contempt.
Interstate cases often implicate UIFSA. Income withholding, contempt, license suspension, and tax-refund intercept remain core tools nationwide, but the Missouri child support agency and clerk of court procedures control day-to-day collection.
When child support ends
In Missouri, Support generally ends at 18, or continues if the child is enrolled in secondary school, not past 21 in typical statutory scenarios. Orders may extend for disability, secondary education, or other statutory grounds where the statute allows. Always read the judgment language — agreed orders sometimes set a different end date or require a notice of emancipation.
Case law: how Missouri courts apply the guidelines
The opinions below are in the LawDiver corpus. Each block quote is taken from the opinion text so you can jump from this guide into the full decision.
In Re Marriage of Glueck
In Re Marriage of Glueck, 913 S.W.2d 951 (1996)
…court's judgment entered on both parties' motions to modify child support for four children born of the marriage. The trial court terminated father's child support obligation with respect to two children and increased child support payments for the remaining two children from $312.50 per month per child to $388.39 per month per child. Mother contends that the trial court erred…
In Re Marriage of Glueck is worth reading on Missouri child support because the court put the point in its own words: "The trial court terminated father's child support obligation with respect to two children and increased child support payments for the remaining two children from $312.50 per month per child to $388.39 per month per child." Use that passage as the starting point, then read the facts that precede it.
In Re Marriage of Amos
In Re Marriage of Amos, 843 S.W.2d 946 (1992)
…in a manner not complained of; (c) Mike's obligation to pay child support for each child was increased from $120 per month to $288.41 per month, with the increase to be retroactive to April 14, 1989, the date on which the motion to modify was served on Mike. On this appeal Mike contends that the trial court erred in terminating his Tuesday and Thursday visitation, in increasing…
In Re Marriage of Amos is worth reading on Missouri child support because the court put the point in its own words: "Mike's obligation to pay child support for each child was increased from $120 per month to $288.41 per month, with the increase to be retroactive to April 14, 1989, the date on which the motion to modify was served on Mike." Use that passage as the starting point, then read the facts that precede it.
STATE of Missouri, Ex Rel. DEPARTMENT OF SOCIAL SERVICES DIVISION OF CHILD SUPPORT ENFORCEMENT, and Wendy Kost
…ls from the decision of the trial court setting his monthly child support payment at $612.07. As his sole point on appeal, Mr. Kost contends that the trial court erred in ordering him to pay the Form 14 child support amount where the Form 14 did not account for the supplemental security income (SSI) benefits received by the parties’ disabled child and where his support obligati…
On child support, STATE of Missouri, Ex Rel. DEPARTMENT OF SOCIAL SERVICES DIVISION OF CHILD SUPPORT ENFORCEMENT, and Wendy Kost speaks to the Missouri dispute in this passage: "ls from the decision of the trial court setting his monthly child support payment at $612.07. As his sole point on appeal, Mr. Kost contends that the trial court erred in ordering him to pay the Form 14 child support amount where the Form 14 did not account for the supplemental s" The surrounding opinion shows how the court applied that language to the record.
David LEWIS, Appellant, v. DEPARTMENT OF SOCIAL SERVICES, Division of Child Support Enforcement, Karen Cordell and
…the circuit court affirming the decision of the Division of Child Support Enforcement which increased his child support obligation from $25 per week to $506 per month, retroactive to January 14, 1996. On appeal, Mr. Lewis first challenges the authority of the Division to modify a cir *251 cuit court’s child support order, claiming that the Division’s exercise of power violates…
Practitioners open David LEWIS, Appellant, v. DEPARTMENT OF SOCIAL SERVICES, Division of Child Support Enforcement, Karen Cordell and when Missouri child support turns on the distinction in this sentence: "Division of Child Support Enforcement which increased his child support obligation from $25 per week to $506 per month, retroactive to January 14, 1996. On appeal, Mr." Do not lift it out of the facts the court was deciding.
In Re Marriage of Angell
In Re Marriage of Angell, 328 S.W.3d 753 (2010)
…ls a modification judgment that increased his court-ordered child support from $650 per month to $1,200 per month. Father challenges the judgment in two points relied on that claim: 1) no substantial evidence supported the trial court's finding that a substantial and continuing change of circumstances had occurred since the time of the court's prior decree; and 2) the monthly i…
Practitioners open In Re Marriage of Angell when Missouri child support turns on the distinction in this sentence: "ls a modification judgment that increased his court-ordered child support from $650 per month to $1,200 per month. Father challenges the judgment in two points relied on that claim: 1) no substantial evidence supported the trial court's finding that a substantial and continuing c" Do not lift it out of the facts the court was deciding.
DIVISION OF CHILD SUPPORT ENFORCEMENT, Et Al., Annette Morgan, Juvenile, Respondents, v. Christopher M. ESTRADA
…April 20,1994, Morgan and the State of Missouri Division of Child Support Enforcement, through the Office of the Clay County Prosecutor, filed a petition for declaration of paternity and order of support. At the same time, Estrada was preparing to file a petition for declaration of paternity, custody, visitation and support. He filed his action on May 10, 1994. On June 27, 1994…
Practitioners open DIVISION OF CHILD SUPPORT ENFORCEMENT, Et Al., Annette Morgan, Juvenile, Respondents, v. Christopher M. ESTRADA when Missouri child support turns on the distinction in this sentence: "April 20,1994, Morgan and the State of Missouri Division of Child Support Enforcement, through the Office of the Clay County Prosecutor, filed a petition for declaration of paternity and order of support." Do not lift it out of the facts the court was deciding.
STATE of Missouri, DEPARTMENT OF SOCIAL SERVICES, Division of Family Support, Appellants, v. Richard STIPANCICH and
…t’s orders that Richard Sti-pancich and Peter Howard IV pay child support. The State initiated separate appeals of the judgments, but, because the appeals presented the same issue, we consolidated them. During September 1996, the circuit court entered a judgment of paternity against Stipancich and ordered him to pay $74 each month in child support. During October 1996, the circ…
STATE of Missouri, DEPARTMENT OF SOCIAL SERVICES, Division of Family Support, Appellants, v. Richard STIPANCICH and is worth reading on Missouri child support because the court put the point in its own words: "Richard Sti-pancich and Peter Howard IV pay child support. The State initiated separate appeals of the judgments, but, because the appeals presented the same issue, we consolidated them." Use that passage as the starting point, then read the facts that precede it.
In re MARRIAGE OF, David Lee CASEY and Janice Michelle Casey
In re MARRIAGE OF, David Lee CASEY and Janice Michelle Casey, 1999 Mo. App. LEXIS 133 (1999)
…appeals the circuit court’s denial of his motion to modify child support. He contends that the circuit court erred in not following mandatory guidelines for use of Form N° 14 under Rule 88.01 and in not ordering his former wife, Janice Michelle Newman, to pay child support for their minor child. We affirm the circuit court’s judgment. Casey and Newman divorced on March 13, 199…
Practitioners open In re MARRIAGE OF, David Lee CASEY and Janice Michelle Casey when Missouri child support turns on the distinction in this sentence: "He contends that the circuit court erred in not following mandatory guidelines for use of Form N° 14 under Rule 88.01 and in not ordering his former wife, Janice Michelle Newman, to pay child support for their minor child. We affirm the circuit court’s judgment." Do not lift it out of the facts the court was deciding.
Practical checklist for Missouri child support matters
- Gather recent pay stubs, tax returns, and proof of health insurance / child-care costs.
- Complete the current Missouri worksheet or financial affidavit required by the local court.
- Document parenting-time overnights if a shared-custody adjustment may apply.
- Flag facts that could support deviation (special needs, travel costs, high income, other children).
- Search LawDiver for recent Missouri appellate decisions before mediation or trial.
Key takeaways
- Missouri follows the Income shares (Form 14) model for presumptive child support.
- Income is generally measured using gross income, then allocated under Mo. Rev. Stat. § 452.340; Missouri Supreme Court Form 14 Directions.
- Guideline amounts are presumptive, not automatic — courts may deviate when the facts justify it.
- Support generally ends at 18, or continues if the child is enrolled in secondary school, not past 21 in typical statutory scenarios.
- Either parent can seek modification when substantial and continuing change; a 20% change in the child support amount is a common statutory threshold..
- Read the companion guide: Missouri alimony / maintenance.
Frequently asked questions
How is child support calculated in Missouri?
Missouri uses the income shares (form 14) under Mo. Rev. Stat. § 452.340; Missouri Supreme Court Form 14 Directions. Courts start with gross income, apply the guideline schedule or percentage, allocate add-ons, and may deviate with findings when the presumptive amount is unjust.
What income counts for Missouri child support?
Guideline income generally tracks gross income as defined by Mo. Rev. Stat. § 452.340; Missouri Supreme Court Form 14 Directions and the worksheets. Wages, self-employment income, bonuses, and certain benefits are commonly included; exact deductions and exclusions are statute-specific.
Can Missouri courts order more or less than the guideline amount?
Yes. Guideline support is presumptive. Judges may deviate when the record shows the guideline result is unjust or inappropriate, typically with written findings explaining the departure.
How do I modify a Missouri child support order?
Substantial and continuing change; a 20% change in the child support amount is a common statutory threshold. File in the court with continuing jurisdiction (or follow UIFSA for interstate cases) and support the request with current financial evidence.
When does child support end in Missouri?
Support generally ends at 18, or continues if the child is enrolled in secondary school, not past 21 in typical statutory scenarios. Confirm any disability, educational, or agreed extensions in your particular order.
Where can I research Missouri child support case law?
Use LawDiver search scoped to Missouri, or open the opinions linked in this guide. Companion reading: Missouri maintenance guide.
Disclaimer
This guide is general legal information about Missouri child support, not legal advice. Statutes, guidelines, and case law change. Confirm the current text of Mo. Rev. Stat. § 452.340; Missouri Supreme Court Form 14 Directions and consult a licensed Missouri family-law attorney about your facts.