https://www.epo.org/en/node/territorial-scope-unitary-patent-and-possible-0

What is the territorial scope of a Unitary Patent?

The geographical scope of the Unitary Patent will eventually cover all the 25 EU Member States that have joined the enhanced cooperation in the area of the creation of Unitary Patent protection. But to be covered by the Unitary Patent, a Member State must not only be participating in this enhanced co‑operation but must also have ratified the Agreement on a Unified Patent Court (UPCA) when unitary effect is registered. A total of 17 states had done so when the new system started on 1 June 2023.

The geographical scope of a given Unitary Patent remains the same for its lifetime and is not extended to those states that ratify the UPCA after its unitary effect has been registered.