What Counts as a Substantial Change in Circumstances for Child Support in Texas

By the FigureMyTax Editorial Team · How we calculate

In Texas, child support modification needs a material and substantial change in circumstances, or three years since the order plus a gap of at least 20% or $100 from the guidelines. Changes reach only obligations accruing after service or appearance.

What is a material and substantial change for child support in Texas?

The statute does not define it; it says the court may modify an order if the circumstances of the child or a person affected by the order have materially and substantially changed since the earlier of the date the order was rendered or the date of a signed mediated or collaborative settlement agreement on which it is based (Tex. Fam. Code 156.401(a)(1)). Incarceration of the obligor for more than 180 days is expressly a material and substantial change (156.401(c-1)).

What is the three-year route?

If it has been three years since the order was rendered or last modified, and the monthly amount differs by either 20 percent or $100 from the amount the guidelines would award, the court may modify without any other change (156.401(a)(2)). The Texas child support modification calculator tests both lines.

With an $800 order, $1,000 is 25% higher and $200 away, so it passes; $880 is 10% and $80 away, so it does not.

How do the guidelines fit in?

The court may use the guidelines to decide whether there has been a material or substantial change that warrants modification, if modification is in the child’s best interest, and if the order does not substantially conform with the guidelines it may modify it to conform, again if in the child’s best interest; it may consider other relevant evidence too (156.402).

Does a new spouse’s income count?

No. The court may not add any part of a new spouse’s net resources to your net resources, or subtract the needs of a new spouse or a new spouse’s dependents from them, in a suit for modification (156.404).

What if my Texas amount was agreed?

If the parties agreed to an order whose amount differs from the guidelines, the court may modify only if the circumstances have materially and substantially changed since the order was rendered (156.401(a-1)). The three-year route does not help.

Does joint conservatorship count in Texas?

No. An order of joint conservatorship, in and of itself, is not grounds for modifying a support order (156.401(c)).

Do medical and dental support matter in Texas?

In a Title IV-D case, a court or administrative order may be modified at any time, and without a showing of a material and substantial change, to provide medical or dental support if the order does not already provide the coverage the statute requires (156.401(a-2)).

From what date can the order change?

A support order may be modified as to the amount only for obligations accruing after the earlier of the date of service of citation or an appearance in the suit to modify, with the incarceration provisions as the exception (156.401(b)). Every month before service is lost:

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 Texas for the filing steps, and check what stays owed with the Texas arrears calculator.

Frequently asked questions

Official sources

• Tex. Fam. Code 156.401: grounds for modification
• Tex. Fam. Code 156.402: effect of guidelines
• Tex. Fam. Code 157.263: confirmation of arrearages
• 42 U.S.C. 666(a)(9): no retroactive modification of support already due
• 45 CFR 302.56: federal guideline requirements

This is general information, not legal advice. It is based on the cited Texas statutes, rules and court opinions, and every case turns on its own facts. Confirm how the law applies to your situation with a licensed Texas attorney.