Best time to fly Hartford to Chicago

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

Best month

May

84.1% on time · 229 flights

Worst month

July

62.1% on time · 199 flights

Month Flights On time Cancelled When late, by
January 162 75.2% 6.79% 66 min
February 148 74.3% 5.41% 106 min
March 171 70.6% 5.26% 74 min
April 226 77.3% 2.21% 113 min
May 229 84.1% 0.87% 79 min
June 204 83.2% 2.94% 98 min
July 199 62.1% 1.51% 121 min
August 207 71.4% 1.93% 102 min
September 206 76.6% 0% 56 min
October 212 72.2% 0% 100 min
November 209 73.1% 5.74% 73 min
December 176 64.2% 1.14% 68 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.