The Legal Status of Cousin Marriage in California
In California, marriage between first cousins is fully legal. The state’s laws do not prohibit or restrict marriage between first cousins, regardless of whether the couple is opposite-sex or same-sex.
Both parties must be over the age of 18 and meet the general requirements for marriage, such as not already being married and providing valid consent.
There are no special conditions—such as age or infertility restrictions—that apply specifically to cousin marriages in California, unlike in some other states.
How California Compares to Other States
California is among a minority of U.S. states that permit first cousin marriage without restriction. While 24 states ban first cousin marriage and 8 states allow it only under certain conditions (such as age or infertility), California stands with 18 states that allow it freely.
In contrast, states like Texas and Oklahoma not only prohibit cousin marriage but may also criminalize it. This patchwork of laws means that while cousin marriage is legal in California, it may not be recognized in other states if you move.
Legal Recognition and Out-of-State Considerations
If you legally marry your first cousin in California, your marriage is fully recognized under California law, granting you all the rights and responsibilities of any married couple.
However, if you move to a state where cousin marriage is prohibited, your marriage may not be recognized there, and you could face legal complications regarding inheritance, spousal rights, or immigration status. Therefore, it is important to consider the laws of any state where you may plan to live in the future.
Cultural and Genetic Considerations
California’s permissive stance reflects its cultural diversity and respect for individual autonomy. In many cultures around the world, cousin marriage is customary and socially accepted, and California’s law acknowledges this diversity.
While some people express concerns about the genetic risks associated with cousin marriage, research shows that the increased risk of birth defects for children of first cousins is relatively small—rising from about 3-4% (unrelated parents) to 5-6% (first cousins).
Nevertheless, couples considering cousin marriage are often advised to seek genetic counseling if they have concerns about hereditary health risks.
First cousin marriage is legal and recognized in California, with no special restrictions beyond the general marriage requirements. While California law is clear, the legality and recognition of cousin marriage can vary significantly in other states.
Anyone considering cousin marriage should be aware of these differences, especially if planning to move, and may wish to consult legal or genetic professionals for guidance.
Sources
[1] https://thewrangler.com/is-it-illegal-to-marry-your-cousin-in-california-heres-what-the-law-says/2025/06/02/
[2] https://www.jlegal.org/blog/is-it-legal-to-marry-your-cousin-in-california/
[3] https://www.linkedin.com/pulse/can-you-marry-your-cousin-law-office-of-james-arrasmith
[4] https://en.wikipedia.org/wiki/Cousin_marriage_law_in_the_United_States
[5] https://www.yeklaw.com/blog/2024/july/immigration-and-marriage-between-cousins/
