England, Wales, and Czechia in February- How warm indoors?

Speaking for the UK, I can only say that generally if I’m shopping in February I’ll probably be wearing some kind of puffa coat, and I might unzip it in a shop and take my woolly hat off, but generally not uncomfortably warm. In a pub you might find an open fire, in which case the coat comes off but probably not the sweater. Museums - I’ve never really noticed the temperature. I guess my coat might go to the cloakroom while I wander around.

Broadly speaking in the UK, we’re much less assertive with our indoor temps than the US. By which I mean we would heat up to a lower temperature in winter but equally in the summer you won’t find aggressive air conditioning.

Cannot speak for Czechia.

I haven’t been to Czechia but my experience in other Eastern European countries that have cold winters is that everything is very warm and cosy indoors.

In the UK it can be more variable. We have a lot of draughty old buildings. The heating might be on but often it doesn’t make things warm enough for my taste in restaurants and cafes. However, it does come down to personal perception and I’m a cold person. Basically, wear layers.

If you’re in London then beware the Tube is always very hot.

Thanks everyone. I'm going for light but flexible so a couple thinner sweaters that can be layered if need be.

In London in winter, the tube is hot and the churches are cold!

That said, January is my favorite time to visit (properly layered, of course)—comparatively low hotel rates, walk right up to popular sights. I imagine February would be similar.