Best time to fly Toronto to London

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

Best month

March

77.6% on time · 50 flights

Worst month

May

40.3% on time · 67 flights

Month Flights On time Cancelled When late, by
January 57 42.1% 0% 0 min
February 49 49% 0% 0 min
March 50 77.6% 2% 0 min
April 61 75% 1.64% 0 min
May 67 40.3% 0% 0 min
June 89 43.2% 1.12% 0 min
July 62 64.5% 0% 0 min
August 62 46.8% 0% 0 min
September 44 72.7% 0% 0 min
October 27 59.3% 0% 0 min
November 30 60% 0% 0 min
December 31 66.7% 3.23% 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.