No, it is not illegal to marry your cousin in Colorado. In fact, Colorado law explicitly allows marriage between first cousins without restriction.
What Does Colorado Law Say?
- First cousin marriage is legal: Colorado permits first cousins to marry. There are no additional requirements or restrictions based on age, fertility, or genetic counseling, unlike some other states that impose such conditions.
- Prohibited relationships: Colorado law does prohibit marriage between certain close relatives, such as:
- Ancestor and descendant (e.g., parent/child, grandparent/grandchild)
- Siblings (brother and sister)
- Aunt/uncle and niece/nephew (with a narrow exception for aboriginal customs)
- Minimum age: Both parties must be at least 18 years old, or 16 with parental/guardian consent.
- No residency requirement: You do not have to be a Colorado resident to get married in the state.
Table: Colorado Cousin Marriage Law
| Relationship | Marriage Legal in Colorado? |
|---|---|
| First cousin | Yes |
| Sibling | No |
| Aunt/Uncle & Niece/Nephew | No (except aboriginal customs) |
| Ancestor/Descendant | No |
Key Points
- Marrying your first cousin is legal in Colorado with no special conditions.
- The law does not distinguish between half-cousins or adopted cousins; both are permitted.
- Colorado is among 18–19 states in the U.S. where first cousin marriage is fully legal.
If you are considering marrying your first cousin in Colorado, state law allows it without restriction. There are no legal barriers specific to cousin marriage in Colorado.
Sources
[1] https://en.wikipedia.org/wiki/Cousin_marriage_law_in_the_United_States
[2] https://www.themonastery.org/marriage-laws/colorado
[3] https://k99.com/cousin-marriage-colorado/
[4] https://www.graham.law/blog/marry-your-cousin-colorado-family-marriage/
[5] https://kekbfm.com/colorado-marry-your-cousin/