What is a key undertaking or key release arrangement? — Property Passport UK guide
Buying a Property

What is a key undertaking or key release arrangement?

Why keys sometimes release only after telegraphic transfer confirmation and how undertakings reduce the risk of buyers occupying before funds clear.

Published: 18 Apr 2026 · Updated: 18 Apr 2026 · 8 min read

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Summary

Key release is sequenced with completion mechanics so sellers are paid before buyers take possession; undertakings formalise how agents or solicitors handle that moment safely.

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