From Swan's "Practical English Usage":
1. We use except (for) after general statements, especially after generalising words like all, every, no, everything, anybody, nowhere, whole, etc.
He ate everything on his plate except (for) the beans.
He ate the whole meal, except (for) the beans.
2. In other cases we usually use "except for", not "except". Compare:
- I've cleaned all the rooms except (for) the bathroom.
(Except is possible after "all".)
- I've cleaned the house except for the bathroom.
(NOT ... except the bathroom.)
- Nobody came except (for) John and Mary. (after "nobody")
- Except for John and Mary, nobody came. (before "nobody")
- You couldn't hear anything except (for) the noise of Louise typing.
- The house was quiet except for the noise of Louise typing.
3. We use "except", not "except for", before prepositions and conjunctions.
It's the same everywhere except in Scotland.
(NOT ... except for in Scotland.)
He's good-looking except when he smiles.
Cited: except/except for | Antimoon Forum
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