How common is ethical non-monogamy, really?
Media coverage of polyamory makes it seem either fringe or ubiquitous. The population data splits the difference, and the gap between what people have tried and what people currently practise is one of the most overlooked findings in relationship research.
How many people have practised ENM?
Approximately 21.9% of US adults have engaged in some form of consensual non-monogamy at some point in their lives, according to a study of 8,718 single Americans published in the Journal of Sex & Marital Therapy (Haupert et al. 2017, n=8,718 · Levine et al. 2018 · Moors et al. 2021
Each dot represents 1 in every 100 US adults. Highlighted: have tried some form of ENM. Source: Haupert et al. 2017, n=8,718 · Levine et al. 2018 · Moors et al. 2021
Who practises ethical non-monogamy?
CNM practice spans all demographic groups. Notably, Haupert et al. 2017, n=8,718 · Levine et al. 2018 · Moors et al. 2021
If you want to explore where you sit on the sexual orientation spectrum, the Kinsey scale test uses the research-backed framework that goes beyond the binary.
Types of consensual non-monogamy
ENM is an umbrella term covering several distinct relationship structures. The estimated shares below are approximate; many people practise hybrid forms, and the categories are not mutually exclusive.
| Type | Description | Est. share of CNM |
|---|---|---|
| Swinging | Couples engage sexually with others together or with permission | 30-40% |
| Polyamory | Multiple romantic and emotional relationships, all consensual | 25-35% |
| Open relationship | Primary partnership with sexual freedom outside it | 25-35% |
| Relationship anarchy | Rejection of hierarchical relationship labels entirely | Small, growing |
| Monogamish | Mostly monogamous with negotiated exceptions | Increasingly reported |
To see how your lifetime partner count compares to the national data, visit the body count calculator.
Are CNM relationships satisfying?
Research consistently finds that people in consensually non-monogamous relationships report comparable or slightly higher relationship satisfaction than those in monogamous relationships, when measured on the same validated scales (Rubin et al. 2014). CNM individuals also report higher self-reported communication quality (Moors et al. 2017).
The caveat: selection effects likely play a role. People who choose CNM invest heavily in communication skills, and those who find it unsatisfying tend to leave, so the satisfied pool may be partially self-selecting.
For relationship frequency context, the sex frequency calculator shows how intimacy frequency compares across relationship stages.
This page is for informational purposes only and does not constitute relationship advice or clinical guidance. Relationship structures are deeply personal. The data presented reflects population-level research and does not imply any structure is healthier or more valid than another. If you are experiencing relationship distress, consider speaking with a licensed therapist.
What does the research say about ethical non-monogamy?
The most widely cited prevalence figure comes from Haupert et al. (2017), a study of 8,718 single US adults across two independent national samples. The finding that roughly 21.9% had engaged in some form of CNM has been replicated in smaller samples. Levine et al. (2018) used the nationally representative 2012 National Survey of Sexual Health and Behavior (N=2,270) to establish that 4-5% of US adults are currently in a CNM arrangement.
The Kinsey Institute's ongoing research programme, led by Amy Moors and colleagues, has been instrumental in moving CNM research beyond clinical stigma into population-level analysis. Their 2021 study found that 31% of US adults express willingness to try CNM, a figure substantially higher than current practice rates. This gap between willingness and practice is consistent with how attitude shifts precede behaviour change on relationship norms.
Is ENM becoming more common?
The research suggests growing openness rather than a dramatic spike in actual practice. Current practice rates (4-5%) have remained relatively stable in the available data, but willingness to try CNM has increased. Media coverage has expanded significantly since 2015, and dating apps now include options for non-monogamous users. Google Trends data shows sustained growth in searches for "ethical non-monogamy" and "polyamory" over the past decade. Mainstream discourse has normalised the concept faster than actual behaviour has shifted, which is consistent with how cultural attitudes typically precede behavioural change.
Frequently asked questions
ENM stands for ethical non-monogamy, an umbrella term for relationship structures where all partners consensually agree that romantic or sexual relationships with others are permitted. The "ethical" qualifier distinguishes it from infidelity: transparency and mutual agreement are the defining features. Common forms include polyamory (multiple romantic relationships), open relationships (a primary partnership with sexual freedom outside it), swinging (couples engaging sexually with others together), and relationship anarchy (rejecting hierarchical relationship labels entirely). The term has gained mainstream visibility since approximately 2015, though the practices it describes have existed across cultures for centuries.
Approximately 1 in 5 US adults (21.9%) have engaged in some form of consensual non-monogamy at some point in their lives, according to a study of 8,718 single Americans published in the Journal of Sex & Marital Therapy (Haupert et al. 2017, n=8,718 · Levine et al. 2018 · Moors et al. 2021
ENM is the umbrella term; polyamory is one form of it. Ethical non-monogamy includes any consensual arrangement where partners agree to non-exclusive relationships: swinging, open relationships, polyamory, relationship anarchy, and other configurations. Polyamory specifically refers to having multiple romantic and emotional relationships simultaneously, with the knowledge and consent of everyone involved. The Moors et al. 2021 study found that 16.8% of US adults had specifically engaged in polyamory, compared to 21.9% who had practised any form of CNM.
Research consistently finds that people in consensually non-monogamous relationships report comparable or even slightly higher relationship satisfaction than those in monogamous relationships, when measured using the same validated scales (Rubin et al. 2014). Key factors that predict satisfaction in CNM relationships include strong communication skills, clear agreements between partners, and a supportive social network. CNM individuals also report higher self-reported communication quality (Moors et al. 2017). Selection effects likely play a role: people who choose CNM tend to invest heavily in relationship communication skills, and those who find it unsatisfying tend to leave.
CNM practice spans all demographic groups, with some notable patterns. LGBTQ+ individuals report significantly higher lifetime CNM experience, at approximately 32% compared to roughly 20% among heterosexual individuals (Haupert et al. 2017, n=8,718 · Levine et al. 2018 · Moors et al. 2021
No. The defining feature of ethical non-monogamy is informed, mutual consent from all parties involved. Cheating, by definition, involves deception or violation of an agreed-upon relationship boundary. In a CNM relationship, all partners know about and agree to the relationship structure, even if the specific agreements vary widely. Levine et al. (2018) specifically distinguished between consensual and nonconsensual nonmonogamy in their research, finding that the motivations, relationship dynamics, and outcomes differ substantially.
Stigma remains one of the most significant challenges for people in CNM relationships. Research by Moors and colleagues (2013) found that 43% of CNM individuals report experiencing stigma from family members, friends, or colleagues. CNM relationships are often perceived as less committed, less satisfying, and more sexually risky than monogamous ones, despite research showing comparable satisfaction and commitment levels. The stigma appears strongest among older generations and more politically conservative populations. Younger adults (18-29) report significantly less negative attitudes toward CNM, suggesting a generational shift in acceptance.
The research suggests growing openness rather than a dramatic spike in actual practice. Current practice rates (4-5%) have remained relatively stable, but willingness to try CNM has increased, with 31% of US adults expressing openness in 2021 (Moors et al. 2021). Media coverage has expanded significantly since 2015, and dating apps now include options for non-monogamous users. Mainstream discourse has normalised the concept faster than actual behaviour has shifted, which is consistent with how cultural attitudes typically precede behavioural change on relationship norms.
- Haupert ML, Gesselman AN, Moors AC, Fisher HE, Garcia JR. (2017). Prevalence of Experiences With Consensual Nonmonogamous Relationships. Journal of Sex & Marital Therapy, 43(5), 424-440. N=8,718.
- Levine EC, Herbenick D, Martinez O, Storme J, Dodge B. (2018). Open Relationships, Nonconsensual Nonmonogamy, and Monogamy Among U.S. Adults. Archives of Sexual Behavior, 47(5), 1439-1450. N=2,270.
- Moors AC, Gesselman AN, Garcia JR. (2021). Desire, Familiarity, and Engagement in Polyamory. Frontiers in Psychology, 12, 619640. N=3,438.
- Rubin JD, Moors AC, Matsick JL, Ziegler A, Conley TD. (2014). On the Margins. Journal fur Psychologie, 22(1).
- Kinsey Institute research programme. Amy Moors et al. kinseyinstitute.org.