Best time to fly Newark to Boston

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

Best month

May

82.9% on time · 348 flights

Worst month

October

50.3% on time · 332 flights

Month Flights On time Cancelled When late, by
January 296 80.8% 6.76% 67 min
February 302 80.5% 8.28% 94 min
March 353 73% 2.27% 53 min
April 347 81% 0% 60 min
May 348 82.9% 0.57% 58 min
June 327 75.7% 1.83% 73 min
July 331 59.3% 10.27% 103 min
August 330 70.3% 0.91% 92 min
September 336 54% 2.98% 75 min
October 332 50.3% 3.01% 69 min
November 327 73% 10.09% 74 min
December 277 76.9% 1.44% 77 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.