Marriage laws can be surprising, especially when it comes to marrying a relative. In the United States, rules about marrying a cousin vary from state to state. In Utah, it’s not always illegal to marry your first cousin, but there are specific conditions that must be met.
This article explains Utah’s laws about cousin marriages, minors getting married, and which marriages are considered void or illegal in the state — in simple, clear language.
Can You Legally Marry Your Cousin in Utah?
Yes, you can marry your first cousin in Utah, but only under certain conditions.
According to Utah State Courts, first cousins may legally marry only if:
Both individuals are over 65 years old, or
Both are over 55 years old and unable to reproduce
This means that younger first cousins cannot legally marry in Utah unless they meet one of these two exceptions. Any other marriage between first cousins — or between people who are more closely related, such as siblings, aunts, uncles, nieces, or nephews — is considered incestuous and void by law.
So, unless you’re over a certain age and medically unable to have children (if between 55 and 65), the state considers cousin marriage illegal.
Why Does Utah Have These Rules?
The age and reproduction rules are in place to prevent the risk of genetic disorders that may arise from closely related individuals having children. By allowing cousin marriage only for older couples or those who can’t reproduce, Utah tries to lower that risk while still giving some freedom to adults who wish to marry a relative.
Is Polygamy Legal in Utah?
Despite what many people think about Utah’s history, polygamy is not legal in Utah. The state constitution and criminal code both prohibit polygamous and plural marriages.
According to Utah law, a person is guilty of bigamy if they marry someone while already being legally married to someone else — or if they try to marry a person who is already married. This law applies even if the other marriage is not officially recognized in court.
Bigamy can be punished as a second-degree or third-degree felony, depending on the situation.
Can Minors Get Married in Utah?
Yes, but only under strict conditions.
In Utah, a minor who is at least 16 years old can get married, but they need:
Signed consent from a parent or legal guardian
Approval from a juvenile court, which will check if the marriage is voluntary and in the minor’s best interests
Recently, a law was passed to strengthen protection for minors. Under this new amendment:
The age gap between the minor and the adult cannot be more than four years
A judge must wait 72 hours after the marriage request is filed before approving it
These changes aim to prevent abuse and ensure that minors are not rushed or forced into marriage.
What Types of Marriages Are Considered Void in Utah?
Some marriages are automatically void in Utah, meaning they are not legally valid, even if they happen. These include:
Marriages where one person is already married to someone else (bigamy)
Marriages between close relatives, such as parent and child, siblings, aunts/uncles and nieces/nephews
Marriages involving minors under 16 years old, unless they have court approval
Marriages between first cousins who do not meet the age or infertility rules
If any of these conditions apply, the marriage is not recognized under Utah law, and it can be legally challenged or annulled.
In Utah, you can marry your first cousin only if both of you are over 65, or over 55 and medically unable to reproduce. Any cousin marriage that doesn’t meet these conditions is considered incestuous and void. Polygamy is also illegal in Utah, and bigamy can lead to serious criminal charges.
While minors aged 16 or 17 can get married with parental and court approval, new laws have made the process stricter to protect young people. Knowing the law helps avoid legal trouble and protects everyone’s rights — especially in such serious matters like marriage.
