Kansas Child Support Guidelines: Calculations and Modifications

The Kansas child support guidelines use an income-shares model: both parents’ incomes are combined, a base support amount is pulled from a schedule keyed to that combined income, the number of children, and the children’s ages, and each parent pays a share of that amount in proportion to their share of the income. The Kansas Supreme Court adopts the guidelines and last updated them effective July 1, 2025.¹ Federal law requires every state to review its guidelines at least once every four years, and the Kansas Child Support Guidelines Advisory Committee handles that review.

How the Calculation Works

The idea behind income shares is that a child should receive the same portion of parental income the family would have spent on them under one roof. Kansas courts run the numbers on a standardized worksheet, and the sequence is the same in every case.

Each parent starts by reporting gross income from all sources. Allowable deductions come off the top — taxes, certain retirement contributions, and other recognized items — to produce each parent’s child support income. The two figures are added together, and that combined number gets looked up on the Kansas child support schedule, which is built from national data on what families at each income level typically spend on children. The schedule varies by combined income, the number of children, and the children’s ages, and it already reflects a “dissolution burden” reduction to account for the higher cost of running two households.²

Once the base obligation is set, each parent’s share is their percentage of the combined income. A parent who earns 60% of the combined total pays 60% of the base obligation. The worksheet then adds the children’s health and dental insurance premiums and any work-related childcare, splitting those costs on the same income percentages. Anyone asking a Kansas court to set or change support has to file a completed domestic relations affidavit and a proposed child support worksheet.³

What Counts as Income

Kansas defines gross income broadly. It captures anything a parent receives regularly or periodically, and the definition reaches well past a base paycheck:

Bonuses, commissions, incentives, overtime, shift differentials, and vacation pay.
Social Security Disability Insurance, VA disability, workers’ compensation, and employer-provided disability payments.
Military base pay plus Basic Allowance for Housing, Basic Allowance for Subsistence, special pay, and other allowances.
In-kind benefits that reduce a parent’s living expenses, such as an employer-provided vehicle, free housing, or reimbursed meals.
Retirement plan distributions once a parent is eligible for them.

The guidelines use gross wages before any salary reduction for cafeteria-plan benefits, so pre-tax deductions for employer health insurance or an FSA don’t lower the income figure.²

Some money is left out entirely. Public assistance programs like TANF, SSI, food stamps, Medicaid, and Section 8 housing don’t count. Neither does child support received for other children living in either parent’s home.²

Self-Employment and Fluctuating Income

For a self-employed parent, the court looks at gross self-employment income minus documented, reasonable business expenses. Tax returns usually anchor the analysis, and courts often average multiple years to smooth out swings. Full financial disclosure is required, and incomplete reporting can bring penalties.

Imputed Income

When a parent is voluntarily unemployed or deliberately underemployed, a Kansas court can assign an income figure based on what that parent could reasonably earn. Before imputing, the court weighs the parent’s assets, employment history, job skills, education, age, health, criminal record, the local job market, and prevailing wages in the community, and it has to put its reasoning in writing.²

At a minimum, a court can find that a capable parent should earn the federal minimum wage for a 40-hour week. If a parent was fired for misconduct rather than laid off, the court can impute the prior wage, at a level no lower than federal minimum wage. One guardrail: income imputed to the parent with primary custody cannot be used to raise the other parent’s obligation.²

Does a New Spouse’s Income Matter?

Generally, no. A stepparent has no legal duty to support a child from a prior relationship, so a new spouse’s earnings are not added to the calculation. The exception: if a parent stops working or cuts hours because a new spouse pays the bills, the court can impute income based on the parent’s earning capacity.

Parenting Time Adjustments

A parent who spends significant time with the child covers real costs during that time, and the guidelines allow a credit against the base obligation when the non-primary parent has the child at least 35% of the time. School and daycare hours don’t count toward that percentage. Above the threshold, the adjustment is tiered:

35–39% of the child’s time: 10% adjustment.
40–44%: 20% adjustment.
45–49%: 30% adjustment.

A separate reduction of up to 50% for a given month can apply when the child spends 14 or more consecutive days with the non-primary parent, such as during summer break. If a parent has a history of not actually exercising scheduled time, the court can deny the adjustment.²

Equal Parenting Time

When the court finds that true 50/50 parenting time is in the child’s best interest, different formulas apply. Parents splitting time equally on a regular, ongoing basis may qualify for either a shared-expense formula or a direct-expense formula, depending on whether they agree to divide the child’s basic direct costs. These replace the standard parenting time adjustment. They usually reduce, but don’t eliminate, the higher earner’s obligation.²

Adjustments and Deviations

The guideline number is a rebuttable presumption. The court treats it as correct unless someone shows a different amount better serves the child. Adjustments handle predictable costs; deviations handle unusual ones.

Recognized adjustments include the children’s health and dental insurance premiums, work-related childcare, and the overall financial condition of the parties. The financial-condition adjustment matters when a parent takes a second job or overtime after the separation to meet new expenses. If that extra income wasn’t part of household finances before the split, the court has discretion to soften how it hits the calculation.²

A deviation requires the court to make written findings explaining why the guideline amount doesn’t fit and why the deviation is in the child’s best interest. This is where things like extraordinary medical expenses, special education needs, or substantial debt taken on for the child’s benefit get argued. Courts won’t approve a deviation without clear evidence.

When Child Support Ends

Kansas child support generally terminates when a child turns 18. High school changes the timing:

If the child turns 18 before finishing high school, support continues automatically through June 30 of the school year in which they turned 18, as long as they’re still attending.
If the child is still in high school after that June 30, the court can extend support through the school year in which the child turns 19, but only if both parents participated in or knowingly went along with the decision that delayed high school completion.
Parents can agree in writing, with court approval, to extend support beyond age 18 for any reason.

For any extension, a “bona fide high school student” means one enrolled in an accredited high school pursuing a diploma or GED in full compliance with the school’s policies.⁴ Support does not automatically continue through college. Any college contribution has to be a separate agreement between the parents.

Modifying an Existing Order

Kansas provides a clear path to change support when circumstances shift, and the rules depend on how old the current order is.

Within Three Years

If fewer than three years have passed since the order was entered or last modified, the parent asking for a change has to show a “material change in circumstances.” A significant income change, a change in custody, or a change in the child’s needs can qualify.⁵

After Three Years

Once three years have passed, either parent can ask the court to review the order without proving a material change. The court simply recalculates using current incomes and the current guidelines.⁵

The 10% Rule

Kansas uses a practical benchmark for whether a change is “material”: if rerunning the worksheet under current facts would shift the base obligation by 10% or more, that alone is a material change. Some limits apply. Income from a second job or overtime the non-primary parent picked up after the separation isn’t, by itself, grounds for modification. Irregular bonuses paid on no reliable schedule don’t count either. And an increase in the primary parent’s income alone cannot be used to raise the other parent’s obligation.⁶

Retroactivity and Filing

A modification can be made retroactive to the first day of the month after the motion is filed.⁵ File early. If you lose your job in January and file the same month, any reduction the court approves can reach back to February 1 even if the hearing sits until May. Until the court acts, the existing order remains in full force. Don’t stop paying or cut payments on your own.

What Happens if Support Goes Unpaid

The Kansas Department for Children and Families (DCF) runs the state’s child support enforcement program and can use most collection tools without going back to court. Once nonpayment reaches 90 days and arrears top $500, DCF can start using them.⁷ Income withholding is the primary tool: DCF, designated by statute as the “income withholding agency,” directs the employer to deduct support from the paycheck before the parent sees it.⁸ Federal and state tax refunds can be intercepted. Driver’s, professional, and recreational licenses can be restricted. Delinquent support can be reported to credit bureaus. Bank accounts can be garnished with court approval, and liens can be placed against real property and against personal injury or workers’ compensation claims. Casino winnings, lottery prizes, and sports betting payouts can be seized. When arrears reach $2,500, the U.S. State Department can deny, revoke, or restrict the parent’s passport.⁹ If administrative tools don’t work, the case can move to contempt of court, where a parent can face fines or jail until they comply or prove a genuine inability to pay.

1
Kansas Judicial Branch. Kansas Child Support Guidelines
2
Kansas Judicial Branch. Kansas Child Support Guidelines
3
Kansas Office of Revisor of Statutes. Kansas Code 23-3002 – Determination of Amount of Child Support
4
FindLaw. Kansas Code 23-3001 – Child Support
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Kansas State Legislature. Kansas Code 23-3005 – Modification of Child Support
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Kansas Judicial Branch. Kansas Child Support Guidelines
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Kansas Department for Children and Families. Enforcement
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Kansas Office of Revisor of Statutes. Kansas Code 23-3102 – Definitions, Income Withholding Act
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Administration for Children and Families. Passport Denial Program 101