What Counts as a Substantial Change in Circumstances for Child Support in Wisconsin
In Wisconsin, child support can be revised on a substantial change in circumstances, and 33 months since the last order is a ground when support is a dollar amount. Arrears accrued before notice cannot be revised.
What is a substantial change in circumstances for child support in Wisconsin?
A revision of the amount of child support may be made only on a finding of a substantial change in circumstances, and the statute lists changes that may qualify (Wis. Stat. 767.59(1f)). The state agency gives examples: a raise or pay cut that changes the monthly order by more than $50, a change in a child’s placement, ending support for an older child on the case, or the receiving parent beginning public assistance (DCF).
What is the Wisconsin 33-month ground?
The expiration of 33 months after the date of the last child support order, including a revision, is a ground, unless the order states support as a percentage of income. Appellate decisions treat it as a rebuttable presumption and as the legislature’s view of a reasonable time to reconsider support (767.59(1f)(b)). Use the Wisconsin child support modification calculator to test it. With an $800 order and a $1,000 guideline amount, the gap is 25%.
Is the percentage standard fixed?
The guideline rules in DCF 150 set the percentages, and a change in those rules does not by itself justify a revision (DCF 150.01(3)).
Does a Wisconsin rule change count?
No. A modification of any provision of the child support guideline rules shall not in and of itself be considered a substantial change in circumstances (DCF 150.01(3)). A new rule applies to orders set after its effective date.
Does a change in the child’s variable costs count?
Not by itself. The rules say a change in the child’s variable costs is not, in and of itself, a substantial change (DCF 150).
Can Wisconsin parents agree never to change support?
Not in a way a court will enforce. Annotations to the statute hold that a stipulation that bars any change in the amount, or that bars a review for several years, is contrary to public policy and unenforceable.
From what date can the order change?
The court may not revise arrearages that accrued before the date notice of the action was given to the respondent, except to correct previous errors in calculation (767.59(1m); 2021 WI App 40). Every month before notice is lost:
| Monthly difference | Lost after 6 months | Lost after 12 months |
|---|---|---|
| $100 a month | $600 | $1,200 |
| $200 a month | $1,200 | $2,400 |
| $400 a month | $2,400 | $4,800 |
Federal law also bars retroactive modification of support already due (42 U.S.C. 666(a)(9)).
What happens next?
Read how to modify child support in Wisconsin for the filing steps, and check what stays owed with the Wisconsin arrears calculator.
Frequently asked questions
What is a substantial change in Wisconsin child support?
A change the court finds substantial; the statute lists examples, and 33 months since the last order is a ground.
Does a Wisconsin rule change modify my order?
No. It is not by itself a substantial change.
Can Wisconsin parents agree not to modify child support?
A stipulation barring any change is unenforceable as contrary to public policy.
Is the Wisconsin 33-month rule a presumption?
Courts treat it as a rebuttable presumption that a review is reasonable.
Can Wisconsin revise support that accrued before notice?
No, except to correct calculation errors.
Official sources
- Wis. Stat. 767.59(1f): substantial change; 33 months
- Wis. Stat. 767.59: revision of judgment
- Wis. Admin. Code DCF 150: child support guidelines
- DCF: reviewing a court order for a change
- 2021 WI App 40: retroactive revision under 767.59(1m)
- 42 U.S.C. 666(a)(9): no retroactive modification of support already due
A local family law attorney can review your situation — many offer a free consultation.
This is general information, not legal advice. It is based on the cited Wisconsin statutes, rules and court opinions, and every case turns on its own facts. Confirm how the law applies to your situation with a licensed Wisconsin attorney.