Best time to fly London to Singapore

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

Best month

February

83.6% on time · 140 flights

Worst month

June

72.1% on time · 302 flights

Month Flights On time Cancelled When late, by
January 157 74.5% 2.55% 0 min
February 140 83.6% 0% 0 min
March 155 81.1% 4.52% 0 min
April 151 73.8% 1.32% 0 min
May 155 76.6% 0.65% 0 min
June 302 72.1% 1.66% 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.