A form of ethical non-monogamy where a committed couple agrees to outside sexual, and sometimes romantic, connections while keeping the central partnership intact. Unlike polyamory, the emotional commitment usually stays with the primary pair.
Also known as Open marriage, Sexually open relationship.
What open relationships actually cover
Most open relationships share a shape: two people stay committed to each other as the central relationship, and they agree to outside connections that are primarily sexual. The emotional weight stays with the pair. That's the default. But the variation inside that shape is huge.
Some couples are mutually open: both partners pursue outside connections. Others are one-sided, where one partner dates out and the other doesn't, either temporarily or as the standing arrangement. Some practice DADT (don't ask, don't tell): outside activity is permitted but kept out of the shared conversation. Some are event-only (swinging is the clearest subset here, usually with other couples, usually at parties or clubs). Some are "monogamish," Dan Savage's term for relationships that are largely exclusive with permission to stray occasionally under specific conditions. Some open relationships allow outside romance. Many don't, and that's often the line between "we're open" and "we're polyamorous."
Interest is rising. In 2024, open relationship was Google's top trending relationship-related search term, and the Feeld / Kinsey Institute 2024 State of Dating Report found ethical non-monogamy was the single most preferred relationship style among Millennials and Gen X. Books like Deepa Paul's Ask Me How It Works and Molly Roden Winter's More brought the conversation into mainstream publishing.
Where people get it wrong
Opening isn't a fix. Couples who open up to solve a problem (dead sex life, drift, a one-sided crush that won't go away) often discover that opening surfaces the problem instead of solving it. That's not a reason not to do it. It's a reason to know what you're actually signing up for.
"Open" isn't less serious than polyamory. It's a different structure, not a lesser commitment. Some open couples have been at it for twenty years with more relationship maturity than people twice as invested in their one partner.
Emotional lines don't stay where you put them. Most rule sets ("just sex, no feelings") assume feelings are controllable, which they largely aren't. Plan for the possibility that an outside connection becomes more than casual, and agree in advance what you'll do when it happens. You can always not act on the plan. You can't skip having it.
Agreements aren't set-and-forget. An open relationship that works at year one probably needs different agreements by year five. Pencil in when you'll revisit them.
Related terms you'll see
- Polyamory
Overlaps with open relationships but centers multiple emotionally committed relationships rather than a single primary pair.
- Swinging
A subset of open relationships focused on shared sexual experiences, typically at events or with other couples.
- Safer sex agreement
An explicit agreement covering testing schedules, barrier methods, and disclosure across your relationship network.
Frequently asked questions
What is the difference between an open relationship and polyamory?
Open relationships are typically couple-centered and focus on outside sexual connections, keeping emotional commitment within the primary pair. Polyamory centers multiple emotionally committed relationships, where the individual (not the couple) is the organizing unit.
Does opening a relationship fix existing problems?
Usually not. Opening a relationship tends to surface existing problems rather than solve them. Couples who open up to rescue a struggling relationship often find the underlying issues intensify, not resolve.
Are open relationships as satisfying as monogamous ones?
Research supports this. A 2025 meta-analysis of 35 studies found no significant differences in relationship or sexual satisfaction between consensually non-monogamous and monogamous relationships.
Is swinging the same as an open relationship?
Swinging is a subset of open relationships focused on shared sexual experiences, typically with other couples at events or clubs. All swinging relationships are open, but not all open relationships involve swinging.