Wisconsin Child Support Calculator (2025)

How Wisconsin Calculates Child Support

Wisconsin uses the Percentage of Income model for child support calculations, which is one of the simplest models in the United States. Under the Wisconsin Administrative Code Chapter DCF 150, the non-custodial parent pays a fixed percentage of their gross income based solely on the number of children requiring support. This model was originally adopted in 1987 and has been refined through subsequent legislative updates.

The Percentage of Income model is distinctive because, in standard placement situations, it only considers the non-custodial parent's income. The custodial parent's income is not factored into the basic calculation, although it may be considered when courts evaluate whether deviation from the standard is appropriate. This approach is based on the economic principle that parents with higher incomes spend a proportionally larger share on their children's needs.

Wisconsin's Department of Children and Families (DCF) administers the child support program and publishes the guidelines that courts use when establishing or modifying child support orders. The percentage standard creates a rebuttable presumption of the correct amount of support, meaning courts will apply these percentages unless there is a compelling reason to deviate based on specific statutory factors.

Wisconsin distinguishes between three primary placement categories: standard placement (one parent has primary physical placement), shared placement (each parent has at least 25% of overnights, equivalent to 92 nights per year), and split placement (where children are divided between the parents). Each category uses a different calculation method, reflecting the varying costs and responsibilities associated with each arrangement.

Wisconsin Percentage Standards

The core of Wisconsin's child support calculation is the percentage standard. These percentages are applied to the non-custodial parent's gross income to determine the monthly child support obligation. The percentages have remained relatively stable since their initial adoption and represent the estimated cost of raising children relative to parental income.

These percentages are applied to gross income, which means income before taxes and other deductions. This is different from many other states that use net income or adjusted gross income. The use of gross income simplifies the calculation but can sometimes result in a higher nominal obligation compared to states that allow more deductions before applying their formulas.

Why Gross Income?

Wisconsin chose to base child support on gross income for several practical reasons. First, gross income is easier to verify and less subject to manipulation through voluntary deductions or tax planning strategies. Second, it provides a more consistent and predictable basis for calculations across different employment situations. Third, the percentage standards were specifically calibrated using gross income figures, so the percentages already account for the fact that the payer will also be paying taxes on their income.

Shared-Placement Formula in Wisconsin

When each parent has physical placement for at least 25% of overnights per year (92 or more nights), Wisconsin uses the shared-placement formula. This formula recognizes that both parents are directly contributing to the children's expenses during their respective placement time, so the child support obligation should be reduced to reflect the paying parent's direct expenditures during their placement time.

The shared-placement calculation follows a specific process established under DCF 150.04(2):

1. Step 1: Determine each parent's gross monthly income
2. Step 2: Multiply each parent's income by the appropriate percentage standard based on the number of children
3. Step 3: Multiply each parent's obligation by the percentage of time the children spend with the other parent
4. Step 4: The parent with the higher resulting obligation pays the difference between the two amounts

For example, consider two parents sharing placement of 2 children, where Parent A earns $6,000/month gross and has 60% placement, and Parent B earns $4,000/month gross and has 40% placement:

In this example, both amounts are equal, so no support would be exchanged. In practice, the parent with the higher calculated obligation pays the difference. If Parent A's result were $750 and Parent B's were $500, Parent A would pay $250/month to Parent B.

Placement Time Calculation

Wisconsin calculates placement time based on the number of overnights each parent has per year. The total is divided by 365 to determine the percentage. For shared placement to apply, each parent must have a minimum of 92 overnights (approximately 25%). Common shared-placement schedules include alternating weeks (50/50), a 9/5 schedule (roughly 64%/36%), or a 4-3 schedule (57%/43%). The court or parties can agree to any schedule that meets the minimum threshold.

Split Placement Calculations

Split placement occurs when the parents have two or more children and each parent has primary placement of at least one child. In this situation, each parent is treated as both a custodial parent and a non-custodial parent simultaneously. The calculation determines each parent's obligation for the children placed with the other parent, and the net difference is the amount owed.

Under DCF 150.04(3), the split placement calculation works as follows:

1. Calculate each parent's child support obligation for the children placed with the other parent using the standard percentage for that number of children
2. The parent with the higher obligation pays the net difference to the other parent

For example, if Parent A earns $5,000/month and has 1 child, while Parent B earns $3,000/month and has 2 children, Parent A would owe 25% of $5,000 = $1,250 for the 2 children with Parent B, and Parent B would owe 17% of $3,000 = $510 for the 1 child with Parent A. The net obligation would be $1,250 - $510 = $740 from Parent A to Parent B.

Income Types in Wisconsin Child Support

Wisconsin defines gross income broadly for child support purposes under DCF 150.02(13). Virtually all sources of income are included in the calculation, and voluntary deductions from pay generally cannot be used to reduce the support obligation. The following income sources are considered:

• Wages and salary — All gross earnings before taxes and voluntary deductions
• Tips, commissions, and bonuses — Typically averaged over the most recent 2-3 years
• Overtime earnings — Courts decide whether overtime is mandatory or voluntary; mandatory overtime is generally included
• Interest and dividends — From investments, savings accounts, and stock holdings
• Pension and retirement income — Including distributions from 401(k), IRA, and other retirement accounts
• Social Security benefits — Including disability and retirement benefits
• Unemployment compensation — Including any supplemental unemployment benefits
• Workers' compensation — Both temporary and permanent disability payments
• Trust fund income — Distributions from trusts or estates
• Rental income — Net rental income after reasonable expenses
• Self-employment income — Gross receipts minus legitimate, ordinary, and necessary business expenses
• Military allowances — Including housing and subsistence allowances

Income Imputation

If a parent is voluntarily unemployed or underemployed, Wisconsin courts may impute income based on their earning capacity. This means the court assigns income based on what the parent could reasonably earn given their education, work history, health, and the availability of employment in the area. Imputed income is based on the payer's most recent documented earnings or, if those are not available, full-time employment at the federal minimum wage. Courts consider factors such as the parent's work history, education, vocational training, physical and mental health, and the local job market.

Excluded Income

Certain income sources are specifically excluded from the Wisconsin child support calculation:

• Income of a new spouse or domestic partner
• Supplemental Security Income (SSI), which is a needs-based benefit
• Foster care payments
• Child support received for other children
• Food stamps (SNAP benefits) and other public assistance

Low-Income Payer Provisions

Wisconsin recognizes that applying the standard percentages to very low incomes could leave the payer without sufficient resources for basic living expenses. Under DCF 150.04(1)(c), the court may reduce the child support obligation for low-income payers to ensure they retain enough income to maintain a minimum standard of living.

The low-income threshold is generally linked to the federal poverty guidelines. If the non-custodial parent's income is at or below 125% of the federal poverty level, the court has discretion to set support at a reduced amount. The court considers the following factors when determining whether a low-income adjustment is appropriate:

• The parent's actual income from all sources
• The parent's earning capacity and ability to increase income
• The parent's essential living expenses, including housing, food, and transportation to work
• The needs of the children and the custodial parent's ability to provide
• Whether the parent's low income is voluntary or involuntary

Even with a low-income adjustment, Wisconsin courts generally set a minimum support amount rather than eliminating the obligation entirely. This ensures the non-custodial parent maintains a legal and financial connection to the child while protecting their ability to support themselves and remain employed.

High-Income Payer Adjustments

For high-income parents, Wisconsin courts may deviate from the standard percentage if applying it would result in support that significantly exceeds the child's reasonable needs. Under DCF 150.04(1)(b), the court considers the child's actual needs, the standard of living the child would have enjoyed had the parents remained together, and other relevant factors.

There is no specific statutory income cap in Wisconsin, unlike some other states. However, courts typically scrutinize support amounts that exceed the child's demonstrated needs. The high-income analysis involves:

• Documenting the child's actual expenses and needs
• Determining the standard of living during the marriage
• Considering future educational and healthcare needs
• Evaluating whether excess support would primarily benefit the custodial parent rather than the child
• Balancing the child's right to benefit from the parent's income against preventing windfall to the custodial parent

In practice, high-income cases often result in setting a base support amount using the percentage standard for a reasonable portion of income, with additional amounts designated for specific child-related expenses such as private school tuition, extracurricular activities, and healthcare premiums.

Serial Family Provisions

When a parent has child support obligations for children from multiple relationships, Wisconsin applies serial family provisions under DCF 150.04(1)(a). These provisions prevent the total support obligations from becoming unreasonably burdensome while still ensuring each child receives adequate support.

The serial family calculation may reduce the gross income available for the current calculation by deducting court-ordered child support payments for prior-born children. The key rules are:

• Prior-born children: Court-ordered support for children from earlier relationships may be deducted from gross income before calculating the current obligation
• Subsequent children: Support for children born after the current obligation was established generally does not reduce the existing order
• Children living with the payer: The payer may receive a modest credit for children living in their household who are not subject to a support order

Courts evaluate serial family situations on a case-by-case basis, balancing the needs of all children involved while ensuring no child is unfairly disadvantaged by the timing of their birth relative to their siblings from other relationships.

How to Modify Child Support in Wisconsin

Wisconsin allows modification of child support orders when there has been a substantial change in circumstances since the existing order was established. You can request a modification through the court or through the local child support agency (county child support office). The modification process involves demonstrating that circumstances have changed sufficiently to warrant a new calculation.

Grounds for Modification

Wisconsin recognizes several specific grounds for child support modification:

• Significant income change: Either parent's income has changed by 15% or more since the last order
• Change in placement schedule: The custody or placement arrangement has been substantially modified
• 33-month review: At least 33 months have passed since the last order, and the new calculated amount would differ by at least 15% from the current order
• Change in child's needs: The child has developed special medical, educational, or other needs
• Incarceration: The paying parent is incarcerated and unable to earn income (recent legislative changes)
• New children: The payer has additional children requiring support (serial family provisions)

The Modification Process

To initiate a modification in Wisconsin, you can either file a motion directly with the family court or request a review through the county child support agency. The process typically involves:

1. Filing a Motion to Revise Judgment or contacting the county child support agency for a review
2. Providing current financial disclosure, including recent pay stubs, tax returns, and documentation of expenses
3. Serving the other parent with notice of the modification request
4. Attending a hearing or mediation session where both parties present evidence
5. Receiving the court's decision, which may be effective from the date of filing or the date of the hearing

Important: In Wisconsin, child support modifications generally cannot be applied retroactively to a date before the motion was filed or the review was requested. This makes it critical to file promptly when circumstances change rather than waiting and hoping for a retroactive adjustment.

Frequently Asked Questions

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