Do polyamorous relationships last?

The empirical comparison is harder than it sounds. Monogamous-relationship duration is measured against an assumption that one relationship per person is the norm; a polyamorous person who has had several partners over twenty years, three of whom they're still with, is harder to slot into the same comparison. The most useful framings ask not 'does the relationship last' but 'how stable are the core connections.'

On that framing, the answer is reassuring. Studies of polyamorous samples (Conley et al., Moors et al., Cox et al.) consistently find that core polyamorous relationships have stability comparable to monogamous primary partnerships, with similar predictors of longevity — communication quality, conflict resolution skill, attachment security, life-stage compatibility.

Polyamorous communities also tend to have a softer landing for relationship transitions than monogamous norms allow. A relationship that shifts from sexual to romantic-without-sexual, or from cohabiting to long-distance, or from primary to comet, is often described as the relationship evolving rather than ending. The breakup-binary that frames a monogamous relationship's end as failure tends to be less rigid in polyamorous practice.

What the data also shows: relationship-stability outcomes for polyamorous people are not improved by structure itself. People with high attachment security do well in either configuration; people with insecure attachment styles or poor communication infrastructure struggle in either. Polyamory is not a hack for relationship stability; it is just a structure within which good relationship skills produce stable relationships, same as monogamy.