Best time to fly Belfast to Bristol

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

Best month

November

87.7% on time · 122 flights

Worst month

January

66% on time · 239 flights

Month Flights On time Cancelled When late, by
January 239 66% 1.67% 0 min
February 273 75.8% 0% 0 min
March 294 87.4% 0% 0 min
April 286 81.1% 0% 0 min
May 298 77% 0.67% 0 min
June 305 71% 0.66% 0 min
July 158 70.5% 1.27% 0 min
August 158 67.1% 0% 0 min
September 156 73.1% 0% 0 min
October 152 82.1% 0.66% 0 min
November 122 87.7% 0% 0 min
December 146 76.8% 2.74% 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.