Numerous studies conducted in the United States have reported that about four to eight percent of the population are in polyamorous relationships. Polyamory differs from other types of open relationships such as swinging (couples having casual sex outside of the relationship, without being emotionally attached).

How common are poly relationships?

Polyamory Is More Common Than You Think, One in Nine Americans Have Tried It. Will We Stop Having Sex? One in nine Americans have been in a polyamorous relationship, and one in six would like to try one, a study has revealed. Polyamory is a type of relationship where people have multiple romantic and sexual partners.