Alimony in Missouri.
Whether the state sets a formula or leaves it to the judge, what the court has to weigh, how long it runs, and what brings it to an end.
See a different stateMissouri
There is no arithmetic in Missouri’s statute. The court decides the amount and the length from the factors below, and two judges on the same facts can reach different answers. That is not a flaw in how we are describing it; it is how the law is written.
Use the state’s own words
Missouri calls it maintenance. R.S.Mo. 452.335 is captioned 'Maintenance order, findings required for — termination date, may be modified, when' and uses 'maintenance' throughout. 'Alimony' does not appear in the operative text of s. 452.335 or s. 452.370; it appears only in the annotator's case notes appended below the statute on the Revisor's page, which are not statutory text.. Using the state’s own term matters when you are searching for forms or reading an order — the words are not interchangeable across state lines, and some of them mean different things in different places.
The short version4 points · tap one to jump to it
- What the law actually says
- How long it lasts — None. There is no bracket, presumption, cap or schedule tied to the length of the marriage anywhere in s. 452.335. The duration of the marriage is factor (6) in the list and nothing more.
- Does behavior matter? — Expressly relevant, as a listed factor, and stated in unusually broad terms.
- When it ends, and when it can change — There is no cohabitation termination provision in Chapter 452.
In this subject 4
What the law actually says
The short version4 points · tap one to jump to it
- What the law actually says
- How long it lasts — None. There is no bracket, presumption, cap or schedule tied to the length of the marriage anywhere in s. 452.335. The duration of the marriage is factor (6) in the list and nothing more.
- Does behavior matter? — Expressly relevant, as a listed factor, and stated in unusually broad terms.
- When it ends, and when it can change — There is no cohabitation termination provision in Chapter 452.
In this subject 4
The power the court has
What the judge has to weigh
How long it lasts
Duration
None. There is no bracket, presumption, cap or schedule tied to the length of the marriage anywhere in s. 452.335. The duration of the marriage is factor (6) in the list and nothing more. The only durational language in the section is s. 452.335.3: 'The maintenance order shall state if it is modifiable or nonmodifiable. The court may order maintenance which includes a termination date. Unless the maintenance order which includes a termination date is nonmodifiable, the court may order the maintenance decreased, increased, terminated, extended, or otherwise modified based upon a substantial and continuing change of circumstances which occurred prior to the termination date of the original order.' Note the verb: the court 'may' order a termination date. An open-ended award is permitted by the text. Source: https://revisor.mo.gov/main/OneSection.aspx?section=452.335
Does behavior matter?
Marital misconduct
Expressly relevant, as a listed factor, and stated in unusually broad terms. R.S.Mo. s. 452.335.2(9), verbatim: 'The conduct of the parties during the marriage'. The statute does not qualify the phrase, does not define it, does not confine it to sexual misconduct, does not limit it to conduct with economic consequences, and does not restrict it to conduct before separation. It is one of ten factors, so it neither bars nor compels an award. Contrast the mandatory rules in North Carolina and the express bars in Minnesota and Oregon. Source: https://revisor.mo.gov/main/OneSection.aspx?section=452.335
When it ends, and when it can change
What brings it to an end
R.S.Mo. s. 452.370.3, verbatim: 'Unless otherwise agreed in writing or expressly provided in the judgment, the obligation to pay future statutory maintenance is terminated upon the death of either party or the remarriage of the party receiving maintenance.' Note the qualifier 'statutory': the subsection reaches maintenance that the court awarded under s. 452.335, and the default may be displaced by written agreement or by an express provision in the judgment. There is no cohabitation termination provision in Chapter 452. Cohabitation enters only through the modification standard, where s. 452.370.1 directs the court to consider 'the extent to which the reasonable expenses of either party are, or should be, shared by a spouse or other person with whom he or she cohabits'. Source: https://revisor.mo.gov/main/OneSection.aspx?section=452.370
Changing it later
R.S.Mo. s. 452.370.1, verbatim: 'Except as otherwise provided in subsection 6 of section 452.325, the provisions of any judgment respecting maintenance or support may be modified only upon a showing of changed circumstances so substantial and continuing as to make the terms unreasonable. In a proceeding for modification of any child support or maintenance judgment, the court, in determining whether or not a substantial change in circumstances has occurred, shall consider 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 he or she cohabits, and the earning capacity of a party who is not employed.' The threshold is doubled: the change must be both 'substantial' and 'continuing', and it must make the existing terms 'unreasonable'. Modification reaches only installments accruing after personal service: s. 452.370.6, 'The order may be modified only as to support or maintenance installments which accrued subsequent to the date of personal service.' The court also has 'continuing personal jurisdiction over both the obligee and the obligor of a court order for child support or maintenance for the purpose of modifying such order' (s. 452.370.6). Source: https://revisor.mo.gov/main/OneSection.aspx?section=452.370
Worth knowing about Missouri
Three things. First, Missouri requires the decree to declare its own modifiability on its face: s. 452.335.3, 'The maintenance order shall state if it is modifiable or nonmodifiable.' Few states impose that drafting duty by statute, and the consequence is severe, because a maintenance order stated to be nonmodifiable with a termination date cannot afterwards be decreased, increased, terminated, extended or otherwise modified under the same subsection. Second, the modification threshold in s. 452.370.1 expressly directs the court to count the resources of a person the party lives with. The words are 'a spouse or other person with whom he or she cohabits', and the direction is not merely to consider what that person actually contributes but 'the extent to which the reasonable expenses of either party are, or should be, shared'. Third, marital conduct is a listed factor with no limiting words at all, s. 452.335.2(9), 'The conduct of the parties during the marriage'. Missouri retains a fault input in a chapter whose divorce grounds are otherwise built on irretrievable breakdown.
The tax rule changed, and most guides still describe the old one
For a divorce or separation instrument executed after 31 December 2018, alimony is not deductible by the person paying it and not taxable to the person receiving it. The Tax Cuts and Jobs Act repealed the provisions that made it otherwise. For an instrument executed on or before that date the old treatment continues — deductible to the payer, taxable to the recipient — unless it is later modified and the modification expressly adopts the new rule.
This is not a detail. Under the old rule a higher-rate payer could transfer income to a lower-rate recipient and the two of them shared the saving. That saving no longer exists, which changes what a given number is worth to each side. New Hampshire wrote the point into its own statute: its 23 per cent figure assumes non-deductibility, and reverts to 30 per cent if the federal treatment is ever restored.
Alongside the federal rule, Missouri’s own income tax follows the federal treatment. That means the federal answer above is the whole answer here — no state adjustment for alimony either way. Four states do not — Arkansas, California, New Jersey and New York — so this is worth knowing rather than assuming. Worth one more line, because it decides what happens if the federal rule ever changes: Missouri uses rolling conformity, so a change to the federal Internal Revenue Code reaches Missouri automatically, without the legislature having to act. The fifty-state table.
Source: Mo. Rev. Stat. § 143.091 the state source. Confirmed directly by the Missouri Department of Revenue, Income Tax Correspondence, in reply to our question on 24 September 2026: spousal maintenance is tax-neutral for divorces finalized after 31 December 2018 — not deductible for the payer, not taxable to the recipient. The Department did not address instruments executed on or before that date; the federal rule for those is set out above.
The other number that decides your budget
How Missouri calculates child support, and the overnight count that moves it more than income does.
And the question underneath it
What Missouri presumes about custody, and what the judge has to weigh.
The rest of what we have written about Missouri. Every figure is quoted from Missouri’s own statute or its courts’ own published schedule, and carries the date we last checked it.