How common is swinging, really?

This is a harder question to answer than it sounds, because the thing being counted is stigmatised, privately conducted, and defined differently by different researchers.

The most cited finding

The figure that gets quoted most often comes from research using nationally representative US samples, which found that roughly one in five adults reported having engaged in some form of consensual non-monogamy at some point in their lives.

That number is frequently misquoted. It refers to consensual non-monogamy broadly — open relationships, swinging, polyamory and everything else — and to lifetime experience rather than current practice. It does not mean a fifth of the population are swingers.

Current practice is a much smaller number

Estimates of people currently in some form of consensually non-monogamous relationship are much lower, typically in the low single-digit percentages. Swinging specifically is a subset of that again.

Putting a confident number on swinging alone is not really possible with the evidence available. What can be said is that it is a minority practice measured at any given moment, and a considerably less unusual one measured across a lifetime.

Why the numbers are unreliable

• Definitions vary. Some surveys count a single threesome; others require an ongoing arrangement.
• Under-reporting is near-certain. People under-report stigmatised sexual behaviour in surveys, consistently and predictably.
• Sampling is difficult. Much of the research recruits through community forums, which reaches enthusiasts rather than the general population.
• Lifetime and current get conflated. Constantly, including in news coverage of the research.

Numbers you should be sceptical of

Two categories of figure circulate widely and neither is trustworthy.

The first is membership numbers from lifestyle dating platforms. These count accounts rather than people, include inactive and duplicate profiles, and are marketing material. The second is confident-sounding statistics with no citation attached, which tend to be repeated between websites until they acquire an authority they never earned. We do not use either on this site.

What the demographics look like

Research on who participates has generally found a wider spread than the stereotype suggests, with participation reported across age groups, income levels and education levels rather than concentrated among the wealthy and middle-aged.

The one consistent pattern is that most participants arrive as an established couple, and that most are past their twenties. That fits what people describe: this tends to be something couples come to after a few years together rather than at the start.