Best time to fly Nashville to Boston

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

Best month

January

82.1% on time · 335 flights

Worst month

June

67.9% on time · 551 flights

Month Flights On time Cancelled When late, by
January 335 82.1% 6.57% 92 min
February 305 76.6% 4.92% 69 min
March 468 76.2% 1.07% 72 min
April 486 77.9% 0.21% 65 min
May 562 70.7% 0.18% 73 min
June 551 67.9% 0.36% 72 min
July 559 68% 3.4% 67 min
August 526 77.9% 1.71% 70 min
September 531 68.4% 0.38% 73 min
October 617 68.1% 0.81% 77 min
November 452 81.5% 0.22% 86 min
December 413 75.2% 1.21% 57 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.