Best time to fly Birmingham to Paris (Roissy-en-France

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

Best month

March

88.3% on time · 137 flights

Worst month

January

66.7% on time · 118 flights

Month Flights On time Cancelled When late, by
January 118 66.7% 3.39% 0 min
February 117 83.8% 0% 0 min
March 137 88.3% 0% 0 min
April 130 80.6% 0.77% 0 min
May 142 78.7% 0.7% 0 min
June 302 67.3% 0.66% 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.