The legality of cousins marrying varies between states, with 25 prohibiting it outright. However, marriages between cousins that take place in states where such unions are legal are usually recognized in states where they are not legal.
It is legal for first cousins to marry in the following states:
- South Carolina
- Rhode Island
- North Carolina
- New York
- New Mexico
- New Jersey
First cousins may also marry each other in the District of Columbia, too. In North Carolina, double cousin marriage is not legal, however. In Arizona, Illinois, Indiana, Utah and Wisconsin, cousin marriage is only legal between couples who are at least 50 years of age, although the age restrictions vary between states. In Maine, cousins hoping to marry must first obtain a certificate of genetic counseling from a physician. In all other states, cousin marriage is illegal.