Best time to fly Seattle to Indianapolis

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

Best month

November

92.3% on time · 78 flights

Worst month

July

62.3% on time · 123 flights

Month Flights On time Cancelled When late, by
January 57 68.5% 5.26% 37 min
February 49 83.7% 0% 48 min
March 70 79.7% 1.43% 37 min
April 90 80.9% 0% 41 min
May 124 71.8% 0% 32 min
June 120 68.6% 1.67% 51 min
July 123 62.3% 0% 49 min
August 119 66.9% 0.84% 47 min
September 107 67.3% 0% 39 min
October 93 88.8% 3.23% 35 min
November 78 92.3% 0% 47 min
December 86 72.1% 0% 40 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.