When parents separate, an informal child support arrangement can seem like a practical way to keep things simple. One parent agrees to pay a set amount each month, both sides are comfortable with the number, and there is no immediate reason to make the arrangement more complicated.
The difficulty is that child support is not designed to remain frozen while the family’s financial circumstances change. An amount agreed to in 2022 may have been based on income figures, parenting arrangements, and expenses that look very different in 2026. The issue is not simply that life costs more. It is possible that an old informal number may no longer reflect the amount that should actually be paid.
An Old Number May No Longer Be the Right Number
Child support is generally tied to income and the applicable child support guidelines. If the paying parent’s income has increased since 2022, continuing to use the same informal amount can create a growing gap between what is being paid and what current information would support.
The Federal Child Support Tables were also updated effective October 1, 2025. That does not mean every older arrangement automatically changes on that date, but it is another reason parents should not assume a figure calculated years ago remains appropriate indefinitely.
The practical starting point is updated financial information. Depending on the circumstances and the terms of an existing agreement or order, parents may need to exchange current income information so support can be assessed using today’s numbers rather than relying on assumptions about what each person still earns.
Waiting Can Turn a Small Adjustment into a Larger Dispute
One of the risks with a casual agreement is that there may be no built-in review date. If neither parent raises the issue, the same amount can continue for years even while income changes substantially.
