Grammar fix
what time is check-out
ask about check-out
How you ask a hotel by when you must leave your room on the last day.
expressionB1common
Hear it in context
Notice where the phrase sounds natural.
Just to check — what time is check-out tomorrow?
A: Anything else I can help with?
B: Yes — what time is check-out?
Fix the pattern
One small grammar move makes it sound right.
Not: What time I must go out the room?
Say: What time is check-out?
Use the fixed noun 'check-out' (with a hyphen) for the leaving time.