First cousins can legally get married in Utah — plus other marriage laws you may not have known about

SALT LAKE CITY (ABC4) — Did you know that it’s legal to marry your first cousin in Utah? The Beehive state is one of several states where marriage between cousins is allowed — but only in certain cases.

In Utah, first cousins can get married if both parties are over the age of 65 — or if both individuals are over the age of 55 and are “unable to reproduce,” according to Utah State Courts. In all other cases, marriage between relatives is deemed “incestuous and void.”

“You cannot marry your first cousin, or anyone related more closely than a first cousin, such as an aunt, uncle, niece, nephew, parent or child, brother or sister,” Utah State Courts explains.

Utah is one of eight states (Arizona, Illinois, Indiana, Maine, Minnesota, and Wisconsin) that allow some marriages between first cousins, under certain restrictions. Many restrictions in these states deal with age and fertility. Other states either completely prohibit cousin marriage or allow it.

ABC4.com took a look at some of Utah’s other marriage laws that you may not have known about.

Is polygamy legal in Utah?

No, polygamy is not legal in Utah — polygamous and plural marriages were prohibited in the state’s constitution. Utah code restricts bigamy, or marrying someone who is legally married to someone else.

Utah code further says someone is guilty of bigamy if they want to marry another person when one or both parties are already legally married to someone else. Bigamy can be punished as a second- or third-degree felony.

Can you marry a minor in Utah?

In Utah, it is legal for minors to get married if they are at least 16 years old.

Minors aged 16 or 17 need signed consent from their parent or legal guardian, which must be delivered to a county clerk in person. Approval of the marriage must be applied for in juvenile court, which will decide if “the marriage is voluntary and in your best interests.”

During the 2025 legislative session, Sen. Jen Plumb (D) sponsored a bill to amend Utah’s laws regarding marriage to a minor. The amendment decreases the legal age gap from seven years to four years — meaning an adult can only marry a minor if there is not more than a four-year difference in their ages.

The bill also added that a judge may not authorize a minor to be married until it has been at least 72 hours after the minor and their parent/guardian have filed a petition for the authorization.

Which marriages are void in Utah?

There are some situations in Utah where marriages are deemed void, and would be prohibited.

In situations where one party is already married to another person, a marriage is void.

Marriages with minors are also void, unless the minor is 16 or 17 and the marriage has been authorized by the court.

If a decree of divorce is in court but has not been finalized, a new marriage will be void.