Best time to fly Las Vegas to London

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

Best month

August

90.3% on time · 62 flights

Worst month

May

68.3% on time · 165 flights

Month Flights On time Cancelled When late, by
January 159 80.4% 0.63% 0 min
February 133 87.2% 0% 0 min
March 127 83.2% 1.57% 0 min
April 156 88.5% 0% 0 min
May 165 68.3% 0.61% 0 min
June 153 80.8% 1.31% 0 min
July 62 80.6% 0% 0 min
August 62 90.3% 0% 0 min
September 69 75.4% 0% 0 min
October 73 75.3% 0% 0 min
November 60 75% 0% 0 min
December 57 78.6% 1.75% 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.