When a Missouri court establishes a child support order, it reflects the circumstances of both parents and the needs of the child at that moment in time. But life does not stay still. Jobs change, incomes shift, children grow and develop new needs, and custody arrangements evolve. If your existing child support order no longer fits your current reality, you may have more options than you realize.
The short answer to the question “Can my Missouri child support be modified?” is yes, but only under specific legal circumstances. Understanding what qualifies, how to pursue a modification, and what to expect from the process can save you considerable time, money, and frustration.
Once a child support order is handed down, many people believe that they are “stuck” paying that amount of child support for the duration specified in the order. While it is critical to pay the child support according to the judgment, it is possible to have the judgment modified under certain circumstances. Here’s what you need to know.
Related: Child Support Laws in Missouri
Missouri law sets a clear threshold for when a child support order can be revisited. Under Missouri Revised Statutes § 452.370, the provisions of any judgment respecting support may be modified only upon a showing of changed circumstances so substantial and continuing as to make the existing terms unreasonable. That phrase, “substantial and continuing,” carries a lot of legal weight.
Not every change in your life will qualify. The shift in circumstances must be significant enough that keeping the old order in place would be genuinely unfair, and it must be ongoing rather than temporary. A brief dip in income during one slow quarter at work, for instance, is unlikely to meet the bar. A permanent job loss or a major change in a child’s medical needs is a different story.
Missouri law also provides a helpful numerical benchmark. If applying the child support guidelines to the current financial circumstances of both parties would result in a change of child support from the existing amount by 20 percent or more, that constitutes a prima facie showing of a substantial and continuing change in circumstances. In plain terms, if recalculating support under today’s numbers would yield a figure that is at least 20 percent higher or lower than what is currently ordered, that difference itself provides the foundation for a modification request.
For a deeper look at how these calculations work in the first place, our child support overview page walks through Missouri’s income shares model and how courts determine an initial support amount.
A child support order can be modified to go both ways — so the payor is paying either less or more child support, depending on the situation. It is more common for a payor to bring forward a judgment modification case if he or she needs the amount of support lowered, while it is more common for the recipient of child support to bring forward a case if there is grounds to have the amount of child support paid raised.
A job loss, a demotion, a major raise, or a career change that substantially alters one parent’s earnings is one of the most common reasons to seek a modification. If a parent loses their job or experiences a significant reduction in income, they may request a modification to lower their child support obligation. Conversely, if a parent receives a substantial raise or promotion, the other parent may seek an increase in child support based on the new income level.
One important note here: the court will not simply take your word for it that you are earning less. Judges can and do consider your earning capacity, not just your current wages. If a court finds that you are intentionally unemployed or underemployed, it may impute income, meaning it uses the salary it believes you are capable of earning when calculating child support under Form 14. If you voluntarily quit your job or were let go due to misconduct, do not expect the court to reward that with a reduced support obligation.
Children’s financial requirements change as they age. If a child develops special needs or requires additional support, such as medical care or educational expenses, a modification may be warranted. A child who is newly diagnosed with a serious medical condition, for example, may require treatments and ongoing care that the original order never contemplated.
If custody arrangements change, such as one parent gaining primary custody, this can also lead to a modification of child support obligations. Child support and parenting time are closely linked in Missouri, because the amount of overnight parenting time each parent exercises directly affects the Form 14 calculation. Our article on how to approach a motion to modify child custody and support explores this connection in more detail.
When determining whether a substantial change has occurred, the court considers all financial resources of both parties, including the extent to which the reasonable expenses of either party are, or should be, shared by a spouse or other person with whom that party cohabits. If one parent remarries and gains a significant financial partner, that may factor into the analysis, though courts are careful about how much weight they give to a new spouse’s income.
Even if there has been no dramatic change in your situation, Missouri provides a built-in review mechanism. You may request a review of your existing support order from Missouri’s Family Support Division every three years since the order was issued, previously reviewed, or modified, or if there are special circumstances such as a large change in a parent’s income. This administrative pathway can sometimes be faster and less formal than going directly to court, though it is only available in qualifying cases. DivorceNet
Parents seeking a child support modification in Missouri generally have two avenues available to them.
You may request a review by sending a written request by mail to the FSD at P.O. Box 6790, Jefferson City, MO 65102-6790, or by email. If the FSD review shows that you qualify for a modification, the agency will handle the request in court for you. This option tends to be accessible for parents who are already part of the FSD system, but it comes with some limitations in terms of how quickly things move and what kinds of changes the agency can address.
The Motion to Modify Child Support form is a formal pleading to the court that must be filled out completely and verified, meaning sworn to before a notary public, before it can be filed. If the other parent agrees to the modification, the process can move relatively quickly. If the other parent contests it, both sides will have the opportunity to present evidence at a hearing, and a judge will make the final determination.
Our modifications practice page outlines both pathways and explains what to expect at each stage of the process.
If both parents agree on the new terms, the court will typically approve the arrangement as long as it is reasonable and serves the child’s interests. The contested cases are more involved.
Both parties will have the opportunity to present evidence to the court. The judge will review financial records and arguments before issuing a decision, and mediation is available at any time. In fact, the judge can and often will request that the parents meet with a mediator before hearing a contested motion.
To strengthen your position in a contested hearing, preparation matters enormously. You will want to bring pay stubs, tax returns, bank statements, and documentation of any relevant changes in the child’s needs. You will also likely need to present a completed Form 14, Missouri’s child support calculation worksheet, showing what the support amount should be under current circumstances. Use a Missouri child support calculator to estimate the appropriate child support amount based on current income and expenses, and document your financial situation thoroughly. Our child support calculator can help you get a working estimate before your hearing.
One of the most common and costly mistakes parents make is assuming that because they have filed for a modification, they can reduce or stop making payments right away. This is not how Missouri law works.
You must continue paying the original amount until the modification is approved. If you need a child support modification due to a job loss, you must file a formal motion as soon as possible, but the court will not retroactively modify support to a date before you filed. Every dollar of unpaid support during the pendency of your case continues to accrue as a legal debt, and that debt does not disappear when the new order finally takes effect.
This is why timing matters. The moment you experience a substantial change in circumstances, that is the time to consult with a child support attorney and file your motion. Waiting, even with good intentions, only compounds the problem.
A related question that often comes up alongside modification discussions is when child support stops altogether. Missouri’s general rule is that child support payments end when the child turns 18. However, if the child is still in high school, support continues until graduation or the child turns 21, whichever comes first. Support may also continue if the child enlists in the military, becomes self-supporting, gets married, or passes away.
Missouri parents will also continue to be obligated to pay support for children up to age 21 when they are attending college or vocational school, as long as they provide transcripts or other proof that they meet the credit and grade requirements. And for children with significant physical or mental disabilities, support obligations can extend even further. Our article on when child support ends in Missouri goes into greater detail on these exceptions and what you need to document.
Missouri uses what is known as the income shares model to calculate child support. This approach aims to provide the same level of total support children would receive if the family were still together and then divides that amount between the parents based on their incomes. The actual mechanics of the calculation are spelled out in Missouri Supreme Court Rule 88.01 and rely heavily on Form 14.
When a modification is requested, the court runs the current financial figures through the same guidelines used to establish the original order. If the new number comes out 20 percent or more different from the existing order, that is typically sufficient to trigger a formal review. A court will then determine whether the change of circumstances is continuing. If the change is only temporary and for a short period of time, a Missouri court is not likely to modify the child support requirements.
The Missouri Department of Social Services Family Support Division also provides resources for parents navigating support orders, including information on administrative reviews and enforcement.
Child support modification cases can feel deceptively simple on the surface but become complicated quickly once financial records, competing arguments, and the other parent’s objections enter the picture. Courts look at earnings, earning capacity, parenting time, health insurance contributions, childcare costs, and a range of other factors before arriving at a new number.
Having an child support modifications attorney in your corner means having someone who understands how to present your financial documentation clearly, anticipate the other side’s arguments, and make sure the Form 14 calculation accurately reflects your actual circumstances. It also means having someone who can tell you honestly whether your situation qualifies for modification in the first place, before you invest significant time and money into a motion that may not succeed.
At Haefner Law Office, we represent parents on both sides of the modification equation, those seeking a reduction and those seeking an increase. We offer flat-rate pricing that takes the guesswork out of legal fees, so you know what you are getting into from the start. If your child support order no longer reflects your life as it actually is, we encourage you to reach out for a consultation and let us help you figure out your next step.
If you find yourself in a situation where you are no longer making the money you need to pay your child support payments and adequately meet your other financial obligations, it’s critical to get legal help. Back child support will typically still be owed, even if your future payments have been reduced. If you’ve experienced a change in circumstances, don’t wait to submit a request for a modification to the court with the help of a child support modification attorney.
Contact Haefner Law today to learn more about child support modifications by calling (314) 200-6101.
This blog post is intended for general informational purposes only and does not constitute legal advice. For guidance specific to your situation, please consult with a licensed Missouri family law attorney.
Apr 1st, 2026
Child Custody, Child Support, Divorce, Modification
Mar 3rd, 2026
Divorce Mediation, Divorce Mediations, Divorce Process, Family Law