What actually changes legally once you're married?

Marriage changes your legal status in several concrete ways: it affects inheritance rights, next-of-kin recognition, some tax arrangements, and pension or benefit entitlements, and it gives you the option — but not the obligation — to change your surname. None of these happen automatically before the marriage certificate is issued.

Recognition and next of kin

Being legally married gives you formal recognition as next of kin in situations like medical decisions and hospital visiting, which unmarried partners do not automatically have regardless of how long they have been together.

Money and inheritance

Marriage affects inheritance if a partner dies without a will, since spouses have statutory entitlements that unmarried partners do not. It can also affect eligibility for certain tax arrangements, such as marriage allowance, and some pension or benefit calculations.

None of this is retrospective — it applies from the date the marriage becomes legal, not from when you started living together.

Your name

Marriage gives you the right to change your surname using your marriage certificate as evidence, but there is no requirement to do so — many people keep their existing name, and the certificate is valid either way.

What this means for you

Update your will after marrying, since existing wills can be affected by a later marriage.
Keep your marriage certificate safe — you will need it for name changes, financial updates and next-of-kin situations.

Official sources

Last reviewed: 17 August 2026 · Next review due 17 November 2026

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