Best time to fly Austin to Boston

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

Best month

January

76.7% on time · 188 flights

Worst month

July

63.2% on time · 273 flights

Month Flights On time Cancelled When late, by
January 188 76.7% 4.26% 139 min
February 206 76% 5.83% 99 min
March 255 64.1% 2.75% 89 min
April 244 69.6% 0.82% 72 min
May 263 68.6% 0.38% 77 min
June 299 66% 0.67% 81 min
July 273 63.2% 4.03% 72 min
August 267 71.1% 1.5% 100 min
September 257 71.4% 0.78% 98 min
October 271 68% 0.37% 95 min
November 230 71.4% 0.87% 96 min
December 237 71.4% 1.27% 65 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.