Polyamory and consensual non‑monogamous (CNM) relationships are increasingly common. But while social acceptance may be growing, UK law has not yet caught up. That means couples and “throuples” where more than two adults share a committed partnership, often face significant legal uncertainty around their rights and protections.
At Arlingsworth, we provide clear, pragmatic legal advice for polyamorous and non‑monogamous families. Whether you’re entering such a relationship, living together, separating, or planning for the future, our solicitors can help you protect your interests and plan ahead.
Call email or provide us with a few details of your matter by completing the enquiry box and we will endeavour to reply to you within 48 hours.
Secondary (or tertiary) partners do not have an automatic claim to each other’s estates, pensions, or spousal benefits. If someone dies without a valid will, their non‑married partners may be left unprotected.
We can draft legally‑binding (or persuasive) agreements that set out:
Such an agreement can help prevent lengthy disputes and clarify ownership or entitlement, especially if one or more partners are unmarried.
If more than two adults live together, and the property is jointly owned or contributions are shared, disputes may arise about who owns what, or who should benefit if the relationship ends. In the absence of a formal marital status, courts treat such situations like any cohabitation dispute.
Where children are involved, legal parenthood follows standard rules: the birth parents (or those who have satisfied parent‑responsibility requirements) retain parental rights. A third partner not named on the birth certificate may not have any legal rights over the child, even if they have acted as a parent.
If the relationship ends, any legal claims (e.g. over property, finances) are likely limited to what can be proved under trust/property law rather than having the automatic protections a marriage offers.
Because polyamorous relationships fall outside the standard legal framework, you benefit from getting specialist advice and putting protective documents in place early.
CALL OUR EXPERT EMPLOYMENT LAWYERS TODAYWe can draft legally‑binding (or persuasive) agreements that set out:
Yes, being in a polyamorous or consensually non-monogamous relationship is legal. However, UK law does not currently offer legal recognition or protection for relationships involving more than two people.
No. UK law only recognises marriage and civil partnerships between two individuals. Marrying more than one person at the same time is considered bigamy and is a criminal offence.
We recommend creating legally binding agreements such as cohabitation agreements or declarations of trust. These documents clarify ownership, financial contributions, and what happens if the relationship changes or ends.
Not automatically. Parental responsibility can be granted through a formal Parental Responsibility Agreement or a court order, depending on the circumstances and the child’s best interests.
A legally valid will is essential. Without one, only spouses or blood relatives inherit under UK intestacy rules. We can help you draft a will that ensures all partners are protected.