Missouri is a 50/50 custody state by default. Since August 28, 2023, when Senate Bill 35 took effect, state law presumes that equal or approximately equal parenting time is in a child’s best interest.1Missouri Senate. Missouri Senate Bill 35 (2023) That presumption is the starting point in every contested custody case, but it is not the ending point. A judge can and often does order a different schedule when the evidence points that way.
What the Presumption Really Does
The statute calls the 50/50 default a “rebuttable presumption.” The court begins with the assumption that splitting parenting time equally serves the child, and either parent can overcome that assumption by showing, by a preponderance of the evidence, that a different arrangement would be better.2Missouri Revisor of Statutes. Missouri Revised Statutes Section 452.375 – Custody Preponderance means “more likely than not.” It is not a high bar, and parents clear it regularly.
Two situations shut the presumption down without any further analysis. If both parents reach their own custody agreement, the court respects that deal instead of imposing an equal schedule neither parent asked for. And if the court finds a pattern of domestic violence, the presumption drops out entirely and the judge focuses on protecting the child and the victim.2Missouri Revisor of Statutes. Missouri Revised Statutes Section 452.375 – Custody
In every other contested case, the judge works through the best-interest factors to decide whether 50/50 holds.
How a Judge Decides Whether 50/50 Fits
Missouri judges do not have unlimited discretion. The statute lists eight categories of evidence the court must consider, and the judge must put written findings on the record explaining the decision. In practice, these are the inputs that determine whether the equal-time presumption survives in a given case:
- Each parent’s wishes and the parenting plan each one proposes.
- The child’s relationship with each parent, and each parent’s willingness and ability to be actively involved in daily life.
- The child’s relationships with siblings, grandparents, and anyone else who plays a meaningful role.
- Which parent is more likely to support the child’s relationship with the other parent. Courts pay close attention to cooperation; a parent who blocks phone calls, badmouths the other parent, or plays scheduling games loses ground here.
- The child’s adjustment to home, school, and community. Homeschooling by itself cannot be held against a parent.
- Mental and physical health of everyone involved, including any history of abuse.
- Either parent’s intent to relocate.
- The child’s own preferences, when the child is mature enough to express them free of coaching.
No single factor is decisive. A parent with a mental health condition does not automatically lose custody, and a child’s preference does not override everything else. The judge weighs the factors together and explains the result in writing.2Missouri Revisor of Statutes. Missouri Revised Statutes Section 452.375 – Custody
What this means in practice: 50/50 is the default, but a parent who shows the court that cooperation is poor, schedules do not line up, geography makes equal time impractical, or one parent has not been meaningfully involved can convince a judge to order something different.
Legal Custody and Physical Custody Are Two Different Things
When Missouri parents talk about “50/50 custody,” they usually mean physical custody, which is where the child lives and how parenting time is divided. That is only half of what a Missouri custody order addresses. Legal custody covers who makes the big decisions about the child’s health, education, and welfare.2Missouri Revisor of Statutes. Missouri Revised Statutes Section 452.375 – Custody
Joint legal custody means both parents share decision-making authority and are expected to consult each other on significant choices. Sole legal custody puts that authority with one parent. Joint physical custody means both parents have significant time with the child, though “significant” does not require a perfectly even split. Sole physical custody means the child lives primarily with one parent while the other has a visitation schedule.
The two labels operate independently. Joint legal custody is extremely common even when physical custody is not evenly divided. A parent who sees the child every other weekend may still share in major decisions if the order grants joint legal custody. Where parents get tripped up is confusing the two: joint legal custody gives you a voice in decisions, not more overnight time.
When a Parent Does Not Get Unsupervised Time
Equal parenting time assumes both parents can safely have the child unsupervised. Missouri law sets a specific threshold for restricting that: a court cannot limit a parent’s visitation unless it finds that unsupervised visits would endanger the child’s physical health or harm their emotional development.3Missouri Revisor of Statutes. Missouri Revised Statutes Section 452.400 – Visitation Rights
When supervised visitation is ordered, a responsible adult appointed by the court must be present during visits. Certain criminal convictions involving a child victim, including serious sexual offenses and child abuse, automatically bar unsupervised visitation. For cases involving domestic violence or abuse allegations, a parent seeking unsupervised time must demonstrate proof of treatment and rehabilitation before the restriction can be lifted.3Missouri Revisor of Statutes. Missouri Revised Statutes Section 452.400 – Visitation Rights
Relocation Can End a 50/50 Arrangement Fast
A move is one of the quickest ways to make equal parenting time unworkable, which is why Missouri has detailed relocation rules. They apply any time a parent plans to change the child’s primary home for 90 days or more. A temporary absence like a summer trip does not count.4Missouri Revisor of Statutes. Missouri Revised Statutes Section 452.377 – Relocation
The relocating parent must send written notice by certified mail, return receipt requested, to every person with custody or visitation rights at least 60 days before the move. The notice must include the new address (or city, if the exact address is not known yet), the date of the move, the reasons for it, and a proposed revised custody schedule. It must also inform the other parent of the right to file a motion to block the relocation within 30 days of receiving notice.
If the other parent files that motion within the 30-day window, the move is on hold until the court decides the issue. The relocating parent carries the burden of proving the move is made in good faith and serves the child’s best interest. Skipping the notice requirement carries real consequences: the court can treat it as grounds for modifying custody, order the child returned, and require the relocating parent to pay the other side’s attorney fees and expenses.4Missouri Revisor of Statutes. Missouri Revised Statutes Section 452.377 – Relocation
Changing an Existing Custody Order
If you already have a custody order that is not 50/50, the 2023 presumption does not automatically rewrite it. A parent can ask the court to modify custody, but has to show two things: that circumstances have genuinely changed since the last order (or that the court did not know something important when the order was entered), and that the modification serves the child’s best interest.5Missouri Revisor of Statutes. Missouri Revised Statutes Section 452.410 – Custody Decree Modification
Common grounds include a parent’s relocation, a substantial change in work schedule that makes the current arrangement unworkable, a parent’s failure to actually exercise their parenting time, or new safety concerns such as substance abuse or domestic violence. Minor shifts in routine rarely qualify. The change needs to be meaningful enough that keeping the current order in place would no longer serve the child well.
Filing a modification motion does not pause the existing order. You follow the current parenting plan until the court says otherwise, even if you believe the other parent is the reason you need the change.