Best time to fly Zurich to London

Every month pooled across the years on record, so "July" means July generally rather than one particular July. Full ZRH to LHR record →

Best month

February

91.2% on time · 386 flights

Worst month

June

67% on time · 629 flights

Month Flights On time Cancelled When late, by
January 420 76.2% 1.9% 0 min
February 386 91.2% 0.26% 0 min
March 417 84.5% 4.08% 0 min
April 333 77.9% 0.6% 0 min
May 336 78.7% 0.89% 0 min
June 629 67% 1.11% 0 min

What a seasonal pattern can and cannot tell you

Months differ for reasons that repeat — summer thunderstorms in the American interior, winter fog and de-icing in northern Europe, school holidays filling every seat and leaving no slack in the schedule. Those are real and they come back each year.

What the pattern cannot do is forecast a particular flight. A quiet month has late days and a bad month has punctual ones. Treat this as a way to choose between two dates you are indifferent about, not as a promise.