I just got back from a trip to Europe with several intra-Europe flights. My experience was as soon as the aircraft passed through 10,000 feet or so, the seatbelt sign went off and stayed off until landing. There was even a couple times where we hit some minor bumps and I thought the seatbelt sign would come on but it didn’t. There was only one point across eight intra-Europe segments where the sign came on at cruise and the FAs were asked to take their seats for a bit. This has matched my experience on previous trips to Europe too.

Conversely in the US I find the seatbelt sign isn’t turned off until a higher altitude, if it is turned off at all, and I find the seatbelt sign is turned on at the slightest bump and then remains on for a while. I realize the pilots can get busy up in the flight deck worrying about flying the plane, talking to ATC, managing any route deviations, etc but the seatbelt sign seems like a joke in the US to where now my general rule is if the FAs are up and about and haven’t been asked to suspend service and take their seats, I feel comfortable getting up myself.