No, Missouri does not recognize common law marriage. Couples cannot become legally married in Missouri simply by living together, regardless of how long the relationship lasts or how committed it may be.
This is a point many people get wrong, especially long-term partners who share property, finances, or children. Missouri law is clear and has been consistent for a very long time. Below is a fresh, plain-spoken explanation of how Missouri treats marriage, why common law marriage does not exist here, and what that means in real life.
Marriage in Missouri Is a Legal Event, Not a Lifestyle
In Missouri, marriage is not something that develops over time. It is a legal event with a clear starting point.
To be legally married in Missouri, a couple must:
- Obtain a valid marriage license
- Meet the state’s eligibility requirements
- Have the marriage solemnized by an authorized officiant
If those steps are not taken, Missouri law treats the couple as unmarried, no matter how intertwined their lives may be.
Missouri has never allowed marriage to arise informally through cohabitation or mutual understanding alone.
How Missouri Looks at the Idea of Common Law Marriage
Common law marriage is based on the theory that marriage can be created through intent, cohabitation, and public behavior, even without official approval. In states that recognize it, courts may later decide that a marriage existed based on how the couple lived.
Missouri rejects this idea completely.
From Missouri’s perspective, marriage should never be something people have to argue about after a breakup or death. Either the legal steps were taken, or they were not. The law does not guess, infer, or reconstruct relationships after the fact.
Long-Term Couples Are Not Automatically Married
Missouri law draws a firm line between:
- Being in a committed relationship, and
- Being legally married
A couple can:
- Live together for decades
- Own a home together
- Share bank accounts
- Raise children together
- Be known socially as spouses
And still have no marital rights under Missouri law.
Commitment and marriage are treated as separate things.
What Happens When Unmarried Couples Separate?
Because common law marriage does not exist, separation between unmarried partners is not handled like a divorce.
Property Issues
Missouri’s marital property laws apply only to married spouses. For unmarried couples:
- Property generally belongs to whoever owns it or paid for it
- Joint property is divided based on ownership interests
- Courts do not assume a 50/50 split
This can be especially harsh when one partner contributed indirectly or relied on informal agreements.
No Spousal Support
Alimony is available only after a legal marriage. Unmarried partners generally have no right to spousal support after separation.
Children Are Treated Separately
Child custody and child support are determined independently of marriage. Parental obligations exist regardless of marital status.
Death and Inheritance: Where Assumptions Fail
This is where misunderstandings cause the most damage.
If one partner dies without a will:
- The surviving unmarried partner does not automatically inherit
- Assets pass to legal heirs under Missouri law
It does not matter how long the couple lived together. Without marriage or estate planning, the surviving partner may receive nothing.
What If the Relationship Started in Another State?
Missouri will recognize a common law marriage only if:
- It was validly formed in another state that allows common law marriage, and
- It met that state’s legal requirements at the time
Missouri itself does not create or expand common law marriages. Simply moving to Missouri does not change a couple’s legal status.
Common Beliefs That Lead to Legal Trouble
Many disputes begin with assumptions like:
- “We’ve been together long enough”
- “Everyone knows we’re married”
- “Marriage is just paperwork anyway”
In Missouri, that paperwork is exactly what matters.
Practical Protection for Unmarried Couples
Since common law marriage is not an option, planning becomes critical.
Cohabitation Agreements
These can clearly define:
- Who owns what
- How expenses are shared
- What happens if the relationship ends
Missouri courts often enforce clear, voluntary agreements.
Estate Planning
Unmarried couples should strongly consider:
- Wills
- Beneficiary designations
- Powers of attorney
Without these, a surviving partner may have no legal voice at all.
Why Missouri Takes This Approach
Missouri prioritizes certainty over assumption. Clear rules:
- Reduce litigation
- Prevent inheritance disputes
- Protect courts from subjective relationship disputes
The system may feel rigid, but it is designed to avoid chaos later.
Final Takeaway
There is no common law marriage in Missouri.
Living together, sharing finances, raising children, or presenting yourselves as spouses does not create a legal marriage under Missouri law. Without a marriage license and proper legal steps, couples remain unmarried—regardless of how long the relationship lasts.
Missouri may recognize a valid common law marriage formed in another state, but it does not allow new ones to form within its borders.
