Legal with no special conditions.
Legal only with age, fertility or counseling conditions.
Banned. Several also make it a crime.
Legal everywhere in the US.
First-cousin marriage, state by state.
Tap a state to jump to its details.
| State | First cousins | Details |
|---|---|---|
| Alabama | Legal | No special conditions. |
| Alaska | Legal | No special conditions. |
| Arizona | Legal with conditions | Only if both are 65 or older, or one of you can't have children. |
| Arkansas | Banned | First-cousin marriage is void. |
| California | Legal | No special conditions. |
| Colorado | Legal | No special conditions. |
| Connecticut | Banned | Banned for new marriages from October 1, 2025. Earlier marriages stay valid. |
| Delaware | Banned | First-cousin marriage is void. |
| Florida | Legal | A 2026 bill to ban it did not pass. |
| Georgia | Legal | No special conditions. |
| Hawaii | Legal | No special conditions. |
| Idaho | Banned | First-cousin marriage is void. |
| Illinois | Legal with conditions | Only if both are 50 or older, or one of you can't have children. |
| Indiana | Legal with conditions | Only if both are 65 or older. |
| Iowa | Banned | First-cousin marriage is void. |
| Kansas | Banned | First-cousin marriage is void. |
| Kentucky | Banned | Bans marriage "nearer of kin than second cousins," and doesn't recognize ones from other states. |
| Louisiana | Banned | First-cousin marriage is void. |
| Maine | Legal with conditions | Allowed after genetic counseling, with a physician's certificate. |
| Maryland | Legal | No special conditions. |
| Massachusetts | Legal | No special conditions. |
| Michigan | Banned | First-cousin marriage is void. |
| Minnesota | Banned | Narrow exception for some Native American cultural practices. |
| Mississippi | Banned | First-cousin marriage is void. |
| Missouri | Banned | First-cousin marriage is void. |
| Montana | Banned | First-cousin marriage is void. |
| Nebraska | Banned | First-cousin marriage is void. |
| Nevada | Banned | Also a criminal offense. |
| New Hampshire | Banned | First-cousin marriage is void. |
| New Jersey | Legal | No special conditions. |
| New Mexico | Legal | No special conditions. |
| New York | Legal | No special conditions. |
| North Carolina | Legal | Except double first cousins. |
| North Dakota | Banned | Also a criminal offense. |
| Ohio | Banned | First-cousin marriage is void. |
| Oklahoma | Banned | Also a criminal offense. |
| Oregon | Banned | First-cousin marriage is void. |
| Pennsylvania | Banned | First-cousin marriage is void. |
| Rhode Island | Legal | No special conditions. |
| South Carolina | Legal | No special conditions. |
| South Dakota | Banned | Also a criminal offense. |
| Tennessee | Banned | Banned in 2024. |
| Texas | Banned | Banned in 2005, and a criminal offense. |
| Utah | Legal with conditions | Only if both are 65 or older, or 55 or older and unable to have children. |
| Vermont | Legal | No special conditions. |
| Virginia | Legal | No special conditions. |
| Washington | Banned | First-cousin marriage is void. |
| Washington, DC | Legal | No special conditions. |
| West Virginia | Banned | First-cousin marriage is void. |
| Wisconsin | Legal with conditions | Only if the woman is 55 or older, or one of you can't have children. |
| Wyoming | Banned | First-cousin marriage is void. |
Laws change. Tennessee banned first-cousin marriage in 2024 and Connecticut in 2025. Confirm with your county clerk before you plan anything. Some banning states recognize cousin marriages performed elsewhere and some don't.
So what are the actual risks?
Babies of unrelated parents have roughly a 3% chance of a serious birth defect. For first cousins it's roughly 5 to 6%. That's double, but still low in absolute terms. For second cousins the extra risk is under one percentage point.
The risk comes from recessive conditions. Cousins are more likely to carry the same hidden gene variant from a shared grandparent, and a baby who gets that same variant from both parents can be affected. In families where cousin marriage has gone on for generations, the risk stacks up higher.
The good news: it's testable. A carrier screen tells you whether you two carry the same condition. If you don't, most of that extra risk goes away. If you do, you have options, and a genetic counselor can walk you through them.
Around the world
First-cousin marriage is legal in the UK, Canada, most of Europe, Australia and across the Middle East and South Asia. In Pakistan, roughly half of marriages are between relatives. India's Hindu Marriage Act prohibits it except where a community's custom allows, which is common in parts of South India. China and the Philippines ban it.
Not sure if you're cousins at all?
That's more common than you'd think, thanks to adoptions, donor conception and family secrets. Work it out with the cousin calculator, or settle it with DNA.
Cousins? Check your carriers.
A carrier screen shows whether you both carry the same hidden condition. It's the single most useful test a related couple can take before kids.
Cousin marriage questions.
Can you marry your cousin in the US?
It depends on the state and the cousin. Second cousins can marry in all 50 states. First cousins can marry in 17 states and Washington, DC, can marry with conditions in 6 states, and cannot marry in 27 states (as of October 2026).
Can you marry your second cousin?
Yes. Marrying a second cousin is legal in every US state. Second cousins share great-grandparents and about 3% of their DNA, so the added genetic risk is small.
Can you marry your third cousin?
Yes, everywhere in the US. Third cousins share about 1% of their DNA on average, and some share none at all.
Can you marry your first cousin once removed?
In most states, yes. A few states ban marriages "nearer of kin than second cousins," which can include first cousins once removed, so check your state.
What states can you marry your first cousin in?
Alabama, Alaska, California, Colorado, Florida, Georgia, Hawaii, Maryland, Massachusetts, New Jersey, New Mexico, New York, North Carolina, Rhode Island, South Carolina, Vermont and Virginia, plus Washington, DC. Arizona, Illinois, Indiana, Maine, Utah and Wisconsin allow it with conditions.
Can you marry your cousin in Alabama?
Yes. First-cousin marriage is legal in Alabama with no special conditions.
Can you marry your cousin in Florida?
Yes. First-cousin marriage is legal in Florida. A 2026 bill to ban it did not pass.
Can you marry your cousin in California?
Yes. First-cousin marriage is legal in California.
Can you marry your cousin in Texas?
No. Texas banned first-cousin marriage in 2005, and it is a criminal offense there.
Can you marry your cousin in Tennessee?
No, not anymore. Tennessee banned first-cousin marriage in 2024.
Can you marry your step-sibling?
Step-siblings aren't blood relatives, and most states allow them to marry. A few states have rules about relationships by marriage, so check yours.
Can you date your cousin?
Dating itself isn't regulated, but a handful of states include first cousins in their incest laws, so a relationship can become legally complicated quickly. Second cousins and beyond are fine everywhere.
Know before
you say "I do."
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