IAH to ORD flight delays

Houston, TX (IAH) Chicago, IL (ORD) · 925 miles

6,080 flights · January 2025 – August 2026 · US Bureau of Transportation Statistics

74.77%

Arrived on time

Within 15 minutes of schedule

1.48%

Cancelled

Share of scheduled flights

82 min

When late, late by

Average across delayed arrivals

22 min

Delay per flight

Averaged over every flight flown

What the record says about this route

Which airline you fly changes the odds here. United Airlines arrived on time 16.4 points more often than Frontier Airlines over the same period on the same route — same airports, same weather, same air traffic control. A gap that survives all of that is about how the two airlines are run.

The season swings this route hard. In September it ran 19.3 points more punctual than in July — a difference bigger than the one between the best and worst airlines on most routes. If the date is flexible, it is worth more than the carrier.

This is one of the heavily flown routes in the record — 6,080 flights in the period. Frequency is itself a form of insurance: when a flight goes wrong there is another one within hours, which is not true of the thin routes elsewhere on this site.

Flights from Houston to Chicago run late more often than the average route, though not severely.

Which airline should you fly on this route?

Over January 2025 – August 2026, United Airlines arrived on time most often on IAH to ORD. Frontier Airlines was late most often. Flights ran closest to schedule in September and worst in July.

Every airline on IAH to ORD

Ranked by how many flights each one operated. A carrier with fewer than 100 flights in the period is listed but not graded.

Airline	Flights	On time	Cancelled	Avg delay	Grade
United Airlines	4,007	78.18%	0.6%	70 min	C
American Airlines	798	67.06%	3.51%	122 min	F
Envoy Air	359	72.8%	1.11%	62 min	D
Republic Airways	357	71.68%	3.64%	80 min	D
Spirit Airlines	305	65.98%	4.59%	70 min	F
Frontier Airlines	248	61.83%	2.82%	130 min	F
PSA Airlines	4	50%	0%	156 min	—
SkyWest Airlines	2	50%	0%	38 min	—

Month by month

Share of flights that arrived within 15 minutes of schedule, by month flown.

Jul 2025 peak 85 Jun 2026

On-time arrival rate, %

The return leg

ORD to IAH Chicago back to Houston 75.01% on time D

Other routes from Houston

Common questions

Are flights from Houston to Chicago usually delayed?

74.77% of flights on the IAH to ORD route arrived within 15 minutes of schedule, so roughly 3 in every ten arrived late. That is about the same as the average route in this record.

Which airline is most on time from Houston to Chicago?

United Airlines, at 78.18% on time across 4,007 flights. The least punctual on the route was Frontier Airlines at 61.83%.

How often are IAH to ORD flights cancelled?

1.48% of scheduled flights did not operate — about 15 in every thousand. That is in the normal range.

What is the best month to fly Houston to Chicago?

September, when 85.8% of flights arrived on time. The worst was July at 66.5%.

When IAH to ORD flights are late, how late are they?

About 82 minutes on average across the flights that arrived more than 15 minutes behind schedule.

What these figures do and do not tell you

Everything on this page is counted from the flights that actually operated on IAH to ORD during January 2025 – August 2026, as reported by the airlines to the US Bureau of Transportation Statistics. "On time" is the federal definition: arriving at the gate within 15 minutes of the scheduled time.

A route's record is a description of the past, not a forecast. Weather, air traffic control and the aircraft's earlier flights that day drive most delays, and none of them are predictable from a historical rate. What the record does tell you is whether this route runs late more often than others, and which carrier on it has the better history — which is the part you can actually act on when you book.

Cancellations are counted separately from delays because they are a different problem for a traveller: a late flight still gets you there. How the grade is calculated →