Missouri calculates child support using the Form 14 Child Support Amount Calculation Worksheet, an income shares model that combines both parents' adjusted gross income to determine the presumed monthly obligation under RSMo § 452.340. The Missouri Supreme Court issued an updated Form 14 effective January 1, 2026, incorporating a revised Schedule of Basic Child Support Obligations based on the 2024 guideline review. Filing fees for Missouri divorce cases involving children range from $133 to $250 depending on the county, and courts require at least one spouse to have lived in Missouri for 90 days before filing under RSMo § 452.305.
| Key Fact | Detail |
|---|---|
| Calculation Method | Income Shares Model (Form 14 Worksheet) |
| Governing Statute | RSMo § 452.340 |
| Updated Form 14 | Effective January 1, 2026 (ordered March 4, 2025) |
| Filing Fee Range | $133 to $250 depending on county |
| Residency Requirement | 90 days for at least one spouse |
| Waiting Period | 30 days after filing before judgment |
| Support Duration | Until age 18, or age 21 if child is enrolled in college |
| Modification Threshold | 20% or more change from existing amount |
| Grounds for Divorce | No-fault only: "irretrievably broken" |
| Official Form | SC 01 Form 14 (available at courts.mo.gov) |
What Is the Missouri Child Support Calculator?
The Missouri child support calculator is the state's official Form 14 worksheet, a standardized tool that courts use to determine the presumed monthly child support obligation based on both parents' combined adjusted gross income under RSMo § 452.340. Missouri adopted the income shares model, which assumes that children should receive the same proportion of parental income they would have received if the parents lived together. The Missouri Supreme Court updated Form 14 effective January 1, 2026, incorporating revised income schedules from the 2024 guideline review.
The Form 14 child support calculator requires three official documents from the Missouri Courts website: the worksheet itself (SC 01 Form 14), the directions for completing the worksheet (CS 01 DIR), and the Schedule of Basic Child Support Obligations (CS 01 SCH). The schedule provides a lookup table showing the presumed basic child support obligation for combined adjusted gross incomes ranging from $750 to $50,000 per month for one through six children.
Missouri courts treat the Form 14 result as a rebuttable presumption under RSMo § 452.340.8. This means the calculated amount is presumed correct unless a party demonstrates that applying the guidelines would be unjust or inappropriate. Judges may deviate from the calculated amount, but must state written findings explaining the deviation and the amount that would have resulted under the standard calculation.
How Does Missouri's Income Shares Model Work?
Missouri's income shares model calculates child support by combining both parents' monthly adjusted gross incomes, looking up the basic child support obligation on the Form 14 schedule, then dividing that obligation proportionally based on each parent's percentage share of the combined income under RSMo § 452.340. For example, if Parent A earns $4,000 per month (57% of combined income) and Parent B earns $3,000 per month (43%), Parent A would be responsible for 57% of the basic child support obligation.
Gross income under Missouri's child support guidelines includes wages, salaries, commissions, overtime compensation, bonuses, severance pay, pensions, interest, dividends, trust income, annuities, Social Security benefits, workers' compensation benefits, unemployment insurance benefits, disability insurance benefits, and veterans' benefits. Self-employment income is calculated as gross receipts minus ordinary and necessary business expenses. Courts may also impute income to a voluntarily unemployed or underemployed parent based on recent work history, qualifications, and prevailing job opportunities in the community.
The income shares model reflects economic research showing that intact families spend a predictable percentage of combined income on child-rearing. At lower income levels, a higher percentage goes toward children's basic needs. At higher income levels, the percentage decreases but the absolute dollar amount increases. For a combined adjusted gross income of $7,000 per month with one child, the basic obligation is approximately $1,081 per month. For two children at the same income level, the obligation rises to approximately $1,588 per month.
How to Calculate Child Support in Missouri Step by Step
Missouri parents can calculate child support by completing the 10-line Form 14 worksheet, which takes approximately 30 to 60 minutes when both parents' financial information is readily available. Each line of the worksheet builds upon the previous calculation to arrive at the presumed child support amount under RSMo § 452.340. Online tools at form14.teamlex.com and freeform14.com offer automated versions of the worksheet.
Line 1: Enter each parent's monthly gross income. Include all income sources listed in the Form 14 directions. Convert annual income to monthly by dividing by 12. Convert weekly income to monthly by multiplying by 4.33.
Line 2: Calculate adjustments to gross income. Subtract court-ordered child support obligations for other children that are actually being paid. Subtract one-half of the self-employment tax actually paid. Subtract the cost of a health insurance plan for the parent only (not the children being calculated).
Line 3: Determine adjusted monthly gross income for each parent by subtracting Line 2 from Line 1. Add both parents' adjusted incomes to arrive at the combined adjusted monthly gross income.
Line 4: Look up the basic child support obligation on the Schedule of Basic Child Support Obligations (CS 01 SCH) using the combined adjusted gross income and number of children.
Line 5: Calculate each parent's proportionate share of the combined adjusted gross income. Divide each parent's Line 3 amount by the combined total and express as a percentage.
Line 6: Multiply the basic child support obligation (Line 4) by each parent's percentage share (Line 5) to determine each parent's share of the basic obligation.
Line 7: Add the children's portion of health insurance premiums paid by each parent. Only include the marginal cost attributable to the children, not the parent's individual coverage.
Line 8: Add work-related childcare costs for each parent. This includes daycare, after-school care, and summer care expenses necessary for either parent to maintain employment.
Line 9: Calculate the total child support obligation by combining Lines 6, 7, and 8 for each parent.
Line 10: Determine the presumed child support amount. The parent without primary physical custody pays their Line 9 amount to the custodial parent, minus any direct expenditures (such as health insurance premiums the paying parent covers directly).
What Income Counts for the Missouri Child Support Worksheet?
Missouri's child support worksheet counts virtually all income sources when determining each parent's gross monthly income under RSMo § 452.340. Gross income includes wages and salaries, overtime pay, commissions, bonuses, severance pay, military pay and allowances, pensions, interest, dividends, trust income, annuities, Social Security benefits, workers' compensation, unemployment benefits, disability insurance, and veteran's benefits. Self-employment income equals gross receipts minus ordinary and necessary business expenses.
Missouri courts can impute income to a parent who is voluntarily unemployed or underemployed. If a parent quits a job, reduces hours, or takes a lower-paying position without good cause, the court may base the child support calculation on that parent's earning capacity rather than actual income. Courts examine recent work history, education, occupational qualifications, prevailing job opportunities, and the parent's physical and mental health when imputing income.
Certain income sources are excluded from the gross income calculation. Public assistance benefits (such as Temporary Assistance for Needy Families), Supplemental Security Income (SSI), and Food Stamps are not counted. Child support received for other children from a different case is also excluded from gross income. Foster care payments and adoption subsidies are generally not included.
| Income Type | Included in Gross Income? |
|---|---|
| Wages, Salary, Hourly Pay | Yes |
| Overtime, Bonuses, Commissions | Yes |
| Self-Employment (net of business expenses) | Yes |
| Pensions and Retirement Income | Yes |
| Social Security Benefits | Yes |
| Workers' Compensation | Yes |
| Unemployment Benefits | Yes |
| Disability Insurance | Yes |
| Interest, Dividends, Trust Income | Yes |
| Military Pay and Allowances | Yes |
| Rental Income (net) | Yes |
| TANF / Public Assistance | No |
| Supplemental Security Income (SSI) | No |
| Food Stamps / SNAP | No |
| Child Support from Other Cases | No |
What Factors Can Change the Child Support Amount?
Missouri courts may deviate from the Form 14 presumed child support amount when applying the standard calculation would be unjust or inappropriate, provided the court enters written findings stating the reasons for deviation and the amount that would have been required under the guidelines per RSMo § 452.340.9. Common deviation factors include extraordinary medical expenses, substantial travel costs for parenting time, educational expenses for private school or special needs, and extreme parenting time arrangements.
Extraordinary medical expenses are predictable, recurring costs not covered by insurance, such as dental treatment, orthodontic work, asthma treatment, and physical therapy. One-time medical expenses for illnesses or injuries are typically handled by separate court order rather than inclusion in the Form 14 calculation. Parents often split extraordinary medical expenses in proportion to their respective incomes.
Parenting time adjustments can significantly affect the child support calculation. When the non-custodial parent exercises overnight parenting time for more than the standard schedule, Missouri courts may apply a custody adjustment. Extended parenting time of 92 or more overnights per year (approximately 25% of the year) can trigger an adjustment that reduces the basic child support obligation, reflecting the non-custodial parent's direct expenditures during those additional overnights.
Other deviation factors Missouri courts consider include the financial resources and needs of the child, the financial resources and needs of both parents, the standard of living the child would have enjoyed had the marriage continued, the physical and emotional condition of the child, and the educational needs of the child. Courts also consider whether a parent is voluntarily unemployed or underemployed and whether either parent receives income from a new spouse or cohabitant.
When Does Child Support End in Missouri?
Missouri child support obligations terminate when the child turns 18 years old, or upon earlier emancipation through marriage, entry into active military duty, or becoming self-supporting under RSMo § 452.340.3. Child support may continue until age 21 if the child enrolls in a vocational or higher education institution no later than October 1 following high school graduation and maintains full-time enrollment of at least 12 credit hours per semester with grades sufficient to re-enroll.
The college extension provision under RSMo § 452.340.5 requires the child to actively pursue a degree or certificate. Summer semesters are excluded from the credit-hour requirement. If the child drops below 12 credit hours during a regular semester, fails to maintain grades sufficient for continued enrollment, or reaches age 21, the support obligation terminates at whichever event occurs first. Parents may agree to different terms in a written agreement or the divorce decree may expressly address college support.
The parent receiving support has a legal duty to notify the paying parent when the child becomes emancipated under RSMo § 452.340.6. Failure to provide timely notification makes the receiving parent liable for any support paid after emancipation, plus interest. This provision applies to all forms of emancipation, including turning 18 when no college extension applies, marriage, military service, and court-ordered emancipation.
How Do You Modify Child Support in Missouri?
Missouri allows modification of child support when there has been a substantial and continuing change in circumstances under RSMo § 452.370. A change is presumed substantial if recalculating child support under the current Form 14 guidelines produces an amount that differs from the existing order by 20% or more. This 20% threshold creates a prima facie case for modification, meaning the requesting parent does not need additional evidence that the change is substantial.
Common grounds for modification include job loss, significant income increase or decrease, changes in the child's medical or educational needs, changes in parenting time arrangements, addition of new children to either household, and changes in health insurance costs. The change must be continuing rather than temporary. A parent who loses a job may need to demonstrate ongoing inability to find comparable employment rather than a brief period of unemployment.
To file for modification, a parent submits a Motion to Modify to the court that issued the original child support order. Filing fees for modifications typically range from $50 to $100 depending on the county. The Missouri Division of Child Support Enforcement (DCSE) conducts reviews of child support orders every 3 years upon request, or at any time when a substantial change in circumstances is alleged. Either parent or DCSE can initiate the review process.
| Modification Factor | Impact on Support |
|---|---|
| 20%+ change in Form 14 calculation | Presumed substantial change |
| Job loss or income reduction | May decrease obligation |
| Significant income increase | May increase obligation |
| Change in parenting time schedule | Recalculation required |
| New child in either household | May adjust obligation |
| Change in health insurance costs | Recalculation of Line 7 |
| Child's medical/educational needs change | Deviation analysis |
| DCSE 3-year review | Automatic recalculation |
How Much Does It Cost to File for Child Support in Missouri?
Missouri divorce filing fees range from $133 to $250 depending on the county and whether minor children are involved. As of March 2026, verify with your local clerk. Jefferson County charges $133.50 without children and $233.50 with children. St. Louis County charges $148.50 for all dissolution filings. St. Charles County charges $133 for a dissolution filing. Service of process adds approximately $25 for sheriff delivery of papers.
If child support is part of a divorce (dissolution of marriage), the filing fee covers all issues including property division, maintenance (alimony), and child support. If parents were never married, a parent can establish paternity and seek child support through a separate action, which carries its own filing fee typically ranging from $50 to $150 depending on the county.
Missouri courts offer fee waivers for low-income filers through a Motion and Affidavit in Support of Request to Proceed As a Poor Person. Qualifying individuals must demonstrate inability to pay court costs without substantial hardship. The Missouri Division of Child Support Enforcement (DCSE) can also assist with establishing, enforcing, and modifying child support orders at no cost to the custodial parent through the IV-D program, regardless of whether the parent receives public assistance.
What Are Common Mistakes When Using the Child Support Calculator?
The most common mistake when using Missouri's child support calculator is failing to include all sources of gross income, which can understate the combined adjusted gross income by 15% to 30% and produce an inaccurate presumed support amount. Parents frequently overlook overtime pay, bonus income, rental income, and investment returns when completing Line 1 of the Form 14 worksheet under RSMo § 452.340.
Another frequent error involves health insurance calculations on Line 7. Parents sometimes enter the total family premium rather than the marginal cost attributable to the children. The correct figure is the difference between the parent-only plan cost and the parent-plus-children plan cost. Entering the full family premium inflates the child support calculation and may be challenged in court.
Using outdated income schedules is a critical mistake following the January 1, 2026 Form 14 update. The Missouri Supreme Court revised the Schedule of Basic Child Support Obligations based on the 2024 guideline review. Parents and attorneys using the pre-2026 schedule will arrive at incorrect basic obligation amounts. Always download the current CS 01 SCH schedule from the Missouri Courts website at courts.mo.gov before running calculations.
Additional common errors include failing to account for court-ordered support obligations for other children (Line 2 adjustment), not including work-related childcare costs (Line 8), using net income instead of gross income, and failing to account for imputed income when a parent is voluntarily underemployed. Each of these errors can shift the presumed child support amount by hundreds of dollars per month.
Frequently Asked Questions
Where can I find the official Missouri child support calculator?
The official Missouri child support calculator is Form 14, available for free download from the Missouri Courts website at courts.mo.gov under Child Support Forms. You need three documents: the worksheet (SC 01 Form 14), the directions (CS 01 DIR), and the Schedule of Basic Child Support Obligations (CS 01 SCH). Online automated versions are available at form14.teamlex.com and freeform14.com.
Does Missouri use the income shares model for child support?
Missouri uses the income shares model under RSMo § 452.340, which combines both parents' adjusted gross monthly incomes to determine the basic child support obligation. The obligation is then divided proportionally based on each parent's percentage of the combined income. This model assumes children should receive the same proportion of parental income they would have received in an intact household.
What is the minimum child support payment in Missouri?
Missouri does not set a fixed statutory minimum child support payment. The Form 14 Schedule of Basic Child Support Obligations begins at a combined adjusted gross income of $750 per month, with the lowest listed obligation being approximately $100 per month for one child. Courts retain discretion to set lower amounts when a parent's income falls below poverty guidelines, but the obligation is rarely set at zero unless the parent is incarcerated or has a documented disability preventing any employment.
Can Missouri child support be modified after the order is entered?
Missouri child support orders can be modified upon showing a substantial and continuing change in circumstances under RSMo § 452.370. A 20% or greater difference between the existing order and a recalculated Form 14 amount creates a presumption of substantial change. Either parent can file a Motion to Modify, and the Division of Child Support Enforcement conducts reviews every 3 years upon request.
How does overtime income affect Missouri child support calculations?
Overtime income is included in gross income for Missouri child support calculations under the Form 14 directions. Courts typically average overtime earnings over the most recent 12 to 24 months to account for fluctuations. If overtime is mandatory and regular, courts treat it as reliable income. If overtime is voluntary and sporadic, courts may exercise discretion in determining how much to include, but rarely exclude it entirely.
What happens if a parent hides income from the child support calculator?
Missouri courts have broad authority to investigate hidden income through discovery, subpoenas of financial records, and forensic accounting under RSMo § 452.340. If a court finds that a parent intentionally hid income, the court may impute income based on earning capacity, impose sanctions, award attorney fees to the other parent, and hold the offending parent in contempt of court. Penalties for contempt can include fines and incarceration.
Does parenting time affect child support in Missouri?
Parenting time directly affects Missouri child support calculations. When the non-custodial parent exercises 92 or more overnights per year (approximately 25% of the time), the Form 14 worksheet applies a custody adjustment that reduces the basic child support obligation. The adjustment reflects the non-custodial parent's increased direct expenditures for housing, food, and transportation during extended parenting time.
Can parents agree to a different child support amount than Form 14 calculates?
Missouri parents can agree to a child support amount that differs from the Form 14 presumed amount, but the court must approve the agreement under RSMo § 452.340.9. The court reviews whether the agreed amount is in the child's best interest and requires written findings if it deviates from the guidelines. Courts will not approve agreements that provide significantly less support than the Form 14 amount without compelling justification.
How is self-employment income calculated for Missouri child support?
Self-employment income for Missouri child support equals gross business receipts minus ordinary and necessary business expenses, consistent with IRS reporting principles. Depreciation, home office deductions, and other non-cash expenses may be added back to income at the court's discretion. Courts examine 2 to 3 years of tax returns to establish an average monthly income, accounting for business fluctuations. Newly self-employed parents may need to provide interim financial statements.
What is the new Form 14 effective January 1, 2026?
The Missouri Supreme Court ordered a new Form 14 Child Support Amount Calculation Worksheet on March 4, 2025, with an effective date of January 1, 2026. The updated form incorporates the 2024 Child Support Guideline Review, which revised the Schedule of Basic Child Support Obligations to reflect current economic data on child-rearing costs. All child support calculations filed on or after January 1, 2026 must use the updated Form 14 and revised schedule.