No, it is not illegal to marry your first cousin in Rhode Island. The state permits first-cousin marriages without restrictions, listing only closer relatives like siblings, parents, or grandparents as prohibited under R.I. Gen. Laws § 15-2-1.
Marriage Law Basics
Rhode Island’s marriage statutes define prohibited relationships narrowly: no person may marry a sibling, parent, grandparent, child, grandchild, stepparent, aunt/uncle by blood, niece/nephew, or certain in-laws. First cousins (sharing grandparents) and more distant relations like second cousins or cousins once removed fall outside this list, making them legal.
The law does not require genetic counseling, age minimums beyond general marriage rules (18, or 16 with consent), or proof of infertility for cousins.​
Application Process
Couples apply for a marriage license at any town/city clerk’s office, providing ID, birth certificates, and a $24 fee (as of 2026). The pre-marriage worksheet does not ask about cousin relationships, though clerks may inquire casually—first cousins pose no barrier.
Non-residents can wed anywhere in the state after obtaining a license locally; it expires after 90 days.​
Prohibited Relations Table
| Relation | Legal in RI? |
|---|---|
| First cousins | Yes ​ |
| Second cousins | Yes ​ |
| Half-first cousins | Yes ​ |
| Siblings (full/half) | No ​ |
| Parent-child | No ​ |
| Aunt/uncle-niece/nephew | No ​ |
Health and Social Context
Children of first-cousin unions carry a slightly elevated genetic risk (3-4% higher for birth defects vs. 2-3% general population), but RI imposes no testing mandate. Culturally permissive, RI borders states like Connecticut and Massachusetts that also allow it, reducing “marriage tourism.”
Penalties for Invalid Marriages
Marrying prohibited kin voids the union automatically, risking bigamy charges (felony, up to 5 years). Cousin marriages remain valid indefinitely.
Neighboring States Comparison
Practical Advice
Verify family ties via genealogy if unsure (e.g., distinguish cousins from half-siblings). Couples should consult attorneys for interstate recognition, as some states (e.g., Nevada) ignore out-of-state cousin marriages. RI celebrates such unions without fanfare—focus on standard license steps.
SOURCES:
- https://en.wikipedia.org/wiki/Cousin_marriage_law_in_the_United_States
- https://x.com/grok/status/2024696081687122078
