Do polyamorous people get married?
Yes, frequently. Many polyamorous people are legally married to one partner while having other partners with everyone's full knowledge and consent. The marriage is a legal infrastructure rather than a claim of romantic exclusivity.
Polyamory and legal marriage coexist routinely. A significant portion of polyamorous adults are legally married to one partner; many of those marriages predate the practitioner's identification as polyamorous and have transitioned into polyamorous structures, while others were entered into knowingly as polyamorous from the start.
What the marriage typically is. A legal contract that provides practical infrastructure: tax filing status, healthcare access via spousal benefits, immigration status, automatic next-of-kin authority, inheritance rights. None of these are about romantic exclusivity; they are about the specific bundle of legal benefits and responsibilities the law grants to legally-married couples.
What the marriage often is not, in polyamorous structures. A claim that the spouse is the only romantic partner. A claim that the spouse outranks other partners in all domains. A vow of sexual exclusivity. The vows themselves are usually rewritten to reflect what the partners actually mean — many polyamorous wedding ceremonies replace the standard exclusivity language with commitments about honesty, presence, ongoing choice, and the specific things the partners value.
Commitment ceremonies between partners other than the legal spouse. Many polyamorous polycules also have non-legal commitment ceremonies — handfastings, vow renewals, family-formation rituals — that mark relationships that the law won't recognise but that the people involved want to mark anyway. Some configurations also use multi-partner domestic partnerships in the small but growing number of US municipalities (Somerville, Cambridge, Berkeley, Oakland, others) that recognise them.
Polyamorous divorce. When polyamorous marriages end, the legal process is the same as monogamous divorce. The non-monogamous structure may come up in custody proceedings in some jurisdictions and is one of the legal-risk areas polyamorous parents work to manage proactively. A family-law specialist who handles ENM-aware divorces is a useful person to know about before you need them.