"For whom are you waiting?" should be an accepted translation, as that is the grammatically correct version in English.
Please report and check, "My answer should be accepted"
What's the way to say "Who is waiting for you"
Vem väntar på dig/er?
Are there guidelines as to which verb will end in -ar rather than -er?
No. Most are -ar though. But many common ones are -er...
thanks. you are always such a help
Could you say "På vem väntar ni?" as in the English counterpart "For whom are you waiting?"
You could get away with it as grammatically correct but it just sounds weird.
Godot, of course! - Godot, självklart!