Best time to fly Houston to Charlotte

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

Best month

January

91.1% on time · 190 flights

Worst month

July

64.2% on time · 222 flights

Month Flights On time Cancelled When late, by
January 190 91.1% 11.05% 94 min
February 192 89.9% 1.56% 249 min
March 227 75.6% 2.64% 81 min
April 217 76.2% 1.38% 60 min
May 215 78.6% 0% 114 min
June 200 74.7% 1% 89 min
July 222 64.2% 3.15% 93 min
August 182 70.8% 1.65% 73 min
September 175 87.9% 0.57% 329 min
October 186 82.2% 0.54% 80 min
November 174 83.2% 0.57% 136 min
December 168 85.1% 0% 51 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.