Quick answer: Child support modification in Texas needs either a material and substantial change in circumstances, or three years since the order was rendered or last modified plus a gap of at least 20% or $100 a month from the guideline amount. A modification can reach only obligations that accrue after the earlier of service of citation or an appearance in the suit.
This Texas child support modification calculator applies Tex. Fam. Code 156.401. Enter your current order and the amount the guidelines give today (you can get it from the Texas child support calculator), say whether three years have passed or circumstances changed, and it shows whether the order qualifies and what the gap adds up to.
Texas child support modification at a glance
| Rule | What Texas says |
|---|---|
| Changed circumstances | The circumstances of the child or a person affected by the order have materially and substantially changed since the order was rendered (Tex. Fam. Code 156.401(a)(1)) |
| Three years | Three years since the order was rendered or last modified, and the monthly amount differs by 20 percent or $100 from the guideline amount (156.401(a)(2)) |
| Agreed orders | If the parties agreed to an amount that differs from the guidelines, the court may modify only on a material and substantial change (156.401(a-1)) |
| Start date | Only obligations accruing after the earlier of service of citation or an appearance in the suit to modify (156.401(b)) |
| Incarceration | Over 180 days is a material and substantial change; release is one too if the obligation was abated, reduced or suspended (156.401(c-1), (d)) |
| Medical support | A state-enforced order can be modified at any time, without a material change, to add medical or dental support (156.401(a-2)) |
| Federal rule | Support already due cannot be modified retroactively (42 U.S.C. 666(a)(9)) |
How does child support modification work in Texas?
- Know the two routes. See what counts as a material and substantial change in Texas.
- File and serve promptly. See how to modify child support in Texas.
- Income problems and incarceration. See child support after job loss or incarceration in Texas and, for what stays owed, the Texas child support arrears calculator.
What does this modification calculator check?
The calculator tests the three-year route (a gap of at least 20% or $100) and the changed-circumstances route you report, and shows the monthly gap and the accrued difference from service. It cannot decide whether a court finds a change material and substantial.
Frequently asked questions
What do I have to show to modify Texas child support?
A material and substantial change in circumstances, or three years since the order was rendered or last modified and a monthly amount that differs by 20% or $100 from the guidelines.
Is it 20% or $100 for Texas child support modification?
Either one. The statute says the amount differs by either 20 percent or $100.
From what date can Texas change child support?
Only for obligations accruing after the earlier of service of citation or an appearance in the suit to modify.
Does incarceration count as a change in Texas?
Incarceration of the obligor for more than 180 days is a material and substantial change.
Can a Texas order based on an agreed amount be modified on the three-year route?
No. If the agreed amount differs from the guidelines, the court may modify only on a material and substantial change.