Planning for children's financial future is a top priority during a separation. In the Badger State, the law is clear: children have a legal right to financial support from both parents. To ensure fairness and consistency across all 72 counties, the state uses a set of rules and a Wisconsin child support calculator to determine the appropriate dollar amount for each family.
How does the Wisconsin child support formula work?
The child support formula in Wisconsin is based on a "Percentage of Income Standard." This means the amount a parent contributes is a direct slice of their total pre-tax earnings. The state operates on the belief that a child should have the same standard of living they would have enjoyed if the parents were still living in the same home.
What are the standard percentages for primary placement?
If one parent has primary placement, meaning the child spends more than 75% of the time with them (at least 274 nights per year), the other parent pays a fixed percentage of their gross income.
As of 2026, the standard percentages are:
- 17% for one child.
- 25% for two children.
- 29% for three children.
- 31% for four children.
- 34% for five or more children.
For example, if the paying parent earns a monthly income of $4,000 and has two children in primary placement with the other parent, the Wisconsin child support calculator would set the payment at $1,000 per month ($4,000 x 0.25).
How do overnights change your child support payments?
A major factor in any Wisconsin child support calculator is the tally of "overnights" each parent has per year. In Wisconsin law, the magic number is 92. If both parents have the children for at least 92 nights a year (which is 25% of the time), it triggers the shared placement child support formula.
Why does shared placement lower the payment?
When parents share time, the court uses a more complex math problem. They look at both parents' incomes and the exact percentage of time each person spends with the kids. The logic is that if a child is with you 40% of the time, you are already paying for their food, heat, and toys directly.
To find the final amount in a shared case:
- The court calculates the support amount for both parents as if they were paying the other.
- These amounts are multiplied by 150% to account for the extra cost of running two households.
- Each amount is then multiplied by the percentage of time the other parent has the child.
- The smaller number is subtracted from the larger number, and the parent with the higher remaining obligation pays the difference.
What happens in a 50/50 joint custody split?
Many people assume that joint custody with a perfect 50/50 time split means no one pays support. This is rarely true. If one parent earns $80,000 a year and the other earns $30,000, the higher-earning parent will still likely make child support payments. This ensures the child doesn't live in a mansion one week and a tiny apartment the next. The Wisconsin child support calculator balances the two homes.
What counts as gross income in Wisconsin?
To get an accurate result from a Wisconsin child support calculator, you must use the correct "gross" numbers. Wisconsin defines gross income as your total pay from all sources before any taxes, social security, health insurance, or union dues are taken out.
Is it just my base salary?
No, the child support agency is very thorough. They look at:
- Wages, salaries, tips, and commissions.
- Bonuses and profit-sharing.
- Interest, dividends, and investment earnings.
- Worker’s compensation or disability payments.
- Military allowances like Basic Allowance for Housing (BAH).
- Social Security Disability Insurance (SSDI) payments.
What if a parent refuses to work?
If a parent is "shirking,", which means quitting a job or taking a lower-paying job on purpose to avoid support, the court can "impute" income. This means the judge looks at the parent’s education, past work history, and local job openings in cities like Milwaukee or Madison. The judge then determines what the parent could be earning and bases the child support order on that hypothetical figure.
High Income and Low Income Adjustments
The child support standard changes for parents who fall outside the average income range. Wisconsin has specific "tiers" for very high earners and "self-support reserves" for very low earners.
How is support calculated for high-income?
If a parent's gross income is higher than $7,000 per month ($84,000 per year), the percentages drop for the money earned above that limit. This prevents child support amounts from becoming unfairly large.
Monthly Gross Income | 1 Child | 2 Children | 3 Children |
First $7,000 | 17% | 25% | 29% |
$7,001 to $12,500 | 14% | 20% | 23% |
Over $12,500 | 10% | 15% | 18% |
What if the parent earns very little?
For a paying parent earning less than 150% of the federal poverty level, the court uses the "Low-Income Payer" table. This ensures the parent has enough money left to pay for their own basic needs, like a small flat and food, while still contributing a small amount to their Wisconsin child.
Can you change a child support order later?
Wisconsin law recognizes that life changes. You might get a promotion, lose a job at a factory, or your kids might move in with you full-time. Because of this, child support in Wisconsin is almost always "modifiable."
When should you ask for a review?
The state allows a review every three years. However, you can file a motion with the circuit court sooner if there is a "substantial change in circumstances." This usually means:
- A change in income of 15% or more.
- A major shift in the placement schedule (e.g., going from 80 nights to 150 nights).
- The child reaches age 18 and graduates from high school.
Important Note: Never make a "handshake deal" with your ex to lower the amount. Even if you both agree to $200 instead of $500, the child support order stays at $500 in the eyes of the law. You will continue to build up debt (arrears) until a judge signs a new legal order.
The Role of Child Support Attorneys
While anyone can use a free Wisconsin child support calculator online, the results are only as good as the data you put into it. Child support attorneys are useful when the case gets complicated.
Variable costs are expenses that the monthly support check doesn't cover. These include:
- Daycare or after-school care costs.
- Private school tuition.
- Sports fees, dance lessons, or summer camps.
- Uninsured medical bills like braces or therapy.
A lawyer can help you write a specific agreement that says exactly what percentage each parent pays for these extras. Without this, you might end up in court every time your child needs new cleats or a doctor's visit.
Frequently Asked Questions
Does child support end exactly on the child's 18th birthday?
Usually, but not always. In Wisconsin, support continues until a child turns 18. However, if the child is still in high school or working toward a GED, support continues until graduation or age 19, whichever comes first.
Can the money be taken directly from my paycheck?
Yes. Almost all child support payments in Wisconsin are handled through "income withholding." The money is taken out by your employer and sent to the Wisconsin Support Collections Trust Fund. This is the best way to handle payments because it creates a permanent government record, proving you paid every cent.
What happens if a parent refuses to pay?
Wisconsin takes court orders very seriously. If a parent falls behind, the child support agency has several tools to collect:
- Intercepting federal and state tax refunds.
- Suspending a driver’s license or professional license.
- Placing a lien on a car or a home.
- Reporting the debt to credit bureaus, which drops the payer's credit score.
- Filing a "contempt of court" action, which can lead to jail time.
Wisconsin Support Rules
The Wisconsin child support calculator system is built to provide stability for kids. It ensures that no matter which house the child is sleeping in, they have the resources they need to thrive. By focusing on parents' incomes and a set child support formula, the state reduces the need for parents to argue over every dollar.
If you are currently managing a case, stay organized. Document your overnights accurately, save your pay stubs, and always communicate through official channels or lawyers. If your situation involves a family business, complex stock options, or high-value assets, consider consulting child support attorneys to ensure the calculations are 100% accurate.
For more info on filing forms or checking court records, visit resources like wilawlibrary.gov, countyoffice.org, or courtreference.com. Being informed is the best way to protect your rights and your children’s future.