In the United States, whether you can legally marry your first cousin depends on the laws of the state where you live. Regulations vary substantially nationwide.

Patchwork of State Laws on Cousin Marriage

There is no federal law addressing cousin marriage in the U.S. Rather, each state sets its own policy determining the legality of first cousin unions. This has resulted in a complex patchwork of differing laws across the country.

As of 2023, roughly half of states allow first cousin marriage with no regulations or limitations imposed. However, the other half completely prohibit marriages between first cousins, including double cousins.

Additionally, some states permit it only under certain circumstances, like when both partners are elderly or infertile. The legality of your cousin marriage entirely hinges on the state laws where you reside.

Restrictions and Requirements Vary

States allowing cousin marriage differ on requirements like genetic testing, premarital counseling, and minimum age. Some require cousins to be infertile, while others mandate counseling if the couple is capable of reproducing.

And states banning cousin marriage outright also diverge on specifics like penalties. Most consider it a felony, but punishments range from fines to years in prison. Navigating this maze of disparate laws can prove challenging.

Beyond First Cousins

A handful of states also prohibit marriages between first cousins once removed. And some ban unions between second cousins as well. But most focus limitations specifically on first cousins who are most closely genetically related.

Social Stigma Also Plays a Role

Alongside legal restrictions in many states, social disapproval of cousin marriage persists in America. Even where allowed, cousins often face skepticism and judgment for their relationships.

Laws may be gradually changing toward acceptance, but cultural taboos run deep. Cousins should expect mixed reactions even in states where cousin marriage is legally permitted and recognized.


The patchwork of cousin marriage laws across the 50 states leaves cousins uncertain of their options. There is no blanket federal rule. Those interested must research laws for their home state carefully and also consider potential social consequences. The legal and social treatment of cousin marriage continues evolving over time.