Lease and Flatshare Agreement: What's the Difference?

The lease and the flatshare agreement are regularly confused — sometimes even by flatmates who have signed both. Yet these documents have neither the same role, the same signatories, nor the same effects. Telling them apart means understanding who can claim what from whom.

The Lease: The Link with the Landlord

The lease is the tenancy contract between the landlord and all the flatmates together. It sets the total rent for the property, the duration of the tenancy, and each flatmate's obligations towards the landlord.

Importantly, it generally involves joint liability among the flatmates towards the landlord. In practice, the landlord can claim the full rent from any one of the signatories, regardless of the split they have agreed among themselves.

The Flatshare Agreement: The Link Between Flatmates

The agreement, on the other hand, organises shared living between the flatmates themselves. It splits the rent and charges, sets out what happens when someone moves out or in, and fixes the practical day-to-day rules.

The landlord is not a party to this agreement: they do not sign it, do not need to approve it, and cannot rely on it. It is a document internal to the flatshare.

Why the Two Documents Are Complementary

Each one covers a relationship the other ignores. The lease protects the relationship with the landlord; the agreement protects the relationship between flatmates. Neither replaces the other.

Without an agreement, internal disagreements — who pays for what, how a move-out is handled, what happens to the deposit — get settled case by case, in confusion and often at the worst possible moment. The lease, for its part, says nothing about any of this: that is not what it is for.

A Document That Must Stay Up to Date

Unlike the lease, which stays fixed for its whole duration, the flatshare agreement can and should evolve: a flatmate leaves, another arrives, shares change, new rules get agreed together.

That is exactly where a living agreement makes sense, as opposed to a static PDF signed once and for all. A document that no longer reflects who actually lives in the flatshare protects almost no one.

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