A child support order is written for the family you were on the day a judge signed it. Then life keeps going. A job ends. A raise comes through. A new baby arrives in one household, or a teenager moves in with the other parent. The order doesn't notice any of it.
Texas does let you change the number. It just won't change it for you, and it won't recognize a change the two of you work out over text. Here's how modification actually works in Texas, what qualifies, and the timing mistakes that cost parents real money.
The Two Legal Grounds for Modifying Child Support in Texas
The rule lives in Texas Family Code §156.401. A court may modify a support order if either of these is true:
- A material and substantial change. The circumstances of the child, or of a person affected by the order, have materially and substantially changed since the order was rendered. If the order came out of a mediated or collaborative settlement, the clock starts from whichever came first: the signing of that agreement or the order itself.
- The three-year guideline gap. At least three years have passed since the order was rendered or last modified, and the current monthly amount differs by either 20% or $100 from what the guidelines would award today.
The second path is the one most parents don't know about. You don't have to prove anything dramatic happened. If it's been three years and the math has drifted far enough, that drift is the ground.
There's a catch. If you and the other parent originally agreed to an amount that differed from the guidelines, §156.401(a-1) takes the three-year shortcut off the table. For those orders, only a material and substantial change will do.
What Counts as a Material and Substantial Change
The statute doesn't hand out a checklist, and courts look at each family's facts. The Texas Attorney General's Child Support Division, though, lists the situations it treats as qualifying when it reviews an order:
- The paying parent's income has gone up or down.
- The paying parent is now legally responsible for additional children.
- The children's medical insurance coverage has changed.
- The children now live with a different parent.
A few situations are spelled out in the Family Code itself. Incarceration of the paying parent for more than 180 days is a material and substantial change under §156.401(c-1). So is release from incarceration, if support was reduced or suspended during that time.
Some things that feel like changes don't qualify. Moving to a joint conservatorship isn't, on its own, grounds to modify support (§156.401(c)). Neither is a rise in the receiving parent's lifestyle or standard of living since the last order (§156.405). And a new spouse's paycheck stays out of it entirely. Under §156.404, the court can't add any part of a new spouse's net resources to either parent's income, and it can't subtract the needs of the new spouse's dependents either.
Why a Side Agreement Between Parents Doesn't Change Anything
This is where most of the damage happens. Two parents agree that $400 a month is fair now that one of them got laid off. They shake on it. Then something changes between them, and the receiving parent asks the Attorney General to enforce the order still on file.
The Child Support Division is blunt about how this goes: there are only two ways to change a Texas support order, a court hearing or the Attorney General's Child Support Review Process. Informal agreements between parents don't change the court-ordered amount.
So every month of the handshake deal, the gap between what was paid and what was ordered became arrears. The Attorney General's office notes that unpaid child support carries 6% interest. A $300-a-month shortfall over a year and a half is $5,400 in back support before interest, and that number doesn't care that both parents agreed to it at the time.
The fix is boring but it works. If you and the other parent agree on a new amount, put that agreement in front of a judge so it becomes the order.
Route One: Filing to Modify in Court
A modification is filed in the court that issued the existing order. Under the Family Code, that court keeps what's called continuing, exclusive jurisdiction over the child (§156.001). If your order came out of a Travis County divorce or custody case, the modification usually goes back to Travis County.
Filing yourself, or through an attorney, gives you control over timing. You decide when the petition is filed and when the other parent is served, and timing matters more than most people expect (more on that below). Court is also where you'd go to change custody at the same time, and support often travels with a custody change. If the kids' schedule is shifting too, our guide to the standard possession order covers the default most orders start from.
Route Two: The Attorney General's Child Support Review Process
If you already have an open child support case with the Texas Attorney General, you can ask the office to review the order instead of filing in court yourself. It's free. It's also slower than many parents expect.
Here's the sequence the Child Support Division describes:
- You submit one Request for Review, online or by mail. The office says extra requests can delay processing. It reaches out to both parents within 30 days.
- Staff gather and verify each parent's income, the children's health insurance and both parents' addresses.
- A review specialist looks at the prior orders, how long it's been since the last one and the new guideline calculation, then decides whether to proceed.
- If the review is approved, both parents are invited to a negotiation appointment to draft a new order. If everyone agrees, it goes to a judge to sign. If not, the case goes to a court date.
The office's own estimate is that for most parents, getting a modified order through this process takes at least six months. If the review isn't approved, either parent can still file their own motion to modify in court.
One thing to know before you ask: a review can raise the payment, not just lower it. The Attorney General says plainly that modifications are based on the paying parent's current income. If that parent earns more now than when the order was set, the new number may go up. Run your figures through the Attorney General's monthly child support calculator first.
The Date That Controls How Far Back a Change Reaches
Modification isn't retroactive to the day you lost your job. Under §156.401(b), a court can generally change the amount only for payments that come due after the earlier of two dates: the date the other parent is served with citation, or the date they appear in the modification suit.
Read that slowly if you're the one whose income dropped. Every month you wait to file, and every week the other parent goes unserved, is a month at the old amount that a judge generally can't reach back and fix. In the meantime, the Attorney General's advice is simple: keep paying as much as you can.
Quitting or Cutting Hours Won't Lower Support the Way You'd Think
A judge isn't required to use what you're earning right now. Under Texas Family Code §154.066, if the paying parent's actual income is significantly less than what they could earn because of intentional unemployment or underemployment, the court may apply the guidelines to earning potential instead.
So walking away from a $70,000 job for a $35,000 one doesn't guarantee support gets cut in half. If the court sees the drop as a choice, it can set support on what you're capable of earning. When there's no evidence of income at all, §154.068 tells the court to presume full-time work at federal minimum wage. The Attorney General treats part-time work much the same way, looking at past employment and ability to earn. One limit is written into §154.066 itself: incarceration can't be treated as intentional unemployment.
The Guideline Numbers a Modification Will Be Measured Against
Whether you're testing the 20%-or-$100 gap or estimating a new amount, the comparison point is the guideline schedule in §154.125. For a paying parent with monthly net resources of at least $1,000, the percentages are:
- One child: 20% of net resources
- Two children: 25%
- Three children: 30%
- Four children: 35%
- Five children: 40%, and not less than that for six or more
Below $1,000 a month in net resources, a lower low-income schedule applies, starting at 15% for one child.
Those percentages stop at a cap on monthly net resources. The cap is adjusted for inflation every six years under §154.125(a-1), with each adjustment taking effect on September 1. The 2025 adjustment raised it from $9,200 to $11,700, the figure the Attorney General's own calculator now uses. For one child, that tops the guideline amount out at $2,340 a month. Above the cap, §154.126 lets a court order more depending on both parents' income and the child's proven needs.
If your order was set under the old $9,200 ceiling and the paying parent earns well above it, the new cap alone may open a 20%-or-$100 gap. Whether it does depends on your actual numbers. Our child support practice page walks through how net resources are calculated in the first place.
Common Questions
Can my child support go up if I ask for a modification? Yes. A review looks at current income, not just the change you're worried about. If the paying parent earns more now than when the order was set, the new guideline amount can come out higher. It's worth running the Attorney General's online calculator with real numbers before you file anything.
How long does a child support modification take in Texas? Through the Attorney General's Child Support Review Process, the office says most parents should expect at least six months to get a new order. A court case can be faster or slower depending on whether the other parent agrees and how quickly they're served. Either way, the old amount keeps running until a judge signs the new order.
Does my ex's new spouse's income count in a modification? No. Texas Family Code Section 156.404 bars the court from adding any part of a new spouse's net resources to either parent's income in a modification. It also bars subtracting the needs of the new spouse or the new spouse's dependents.
If I pay extra child support voluntarily, can that be used to raise my order? Not by itself. Under Texas Family Code Section 156.403, a history of paying more than the order requires is not grounds to increase the order. An increase still needs one of the statutory grounds, like a material and substantial change or the three-year guideline gap.
If your income, your household or your kids' living arrangements have changed since the last order, the cheapest time to sort it out is before the arrears pile up. Read how Texas divorce orders set support in the first place, or connect with an Austin family law attorney in our network who handles modifications.
Disclaimer: This article provides general legal information for educational purposes only. It does not constitute legal advice. Whether a child support order can be modified depends on the facts of each case and the terms of the existing order. Consult a licensed Texas attorney about your particular situation.