ORD → IAH Flight Reliability

Right now

Origin · ORDNo disruption reported

Aviation weather is not currently a factor.

Updated 08:51 UTC

Chicago airport profile →

Destination · IAHNo disruption reported

Aviation weather is not currently a factor.

Updated 08:53 UTC

Houston airport profile →

Route reliability

July 2023 – July 2026

Route Reliability Score

61/ 100Good

Better than 38% of comparable major US routes (4,598 compared)

Calculated from 17,017 flights. How this is calculated

On-time arrivals

77.0%

12,886 of 16,736

Cancellation rate

1.32%

224 cancelled

Median arrival delay

-6 min

Average 6.9 min

Severe delays

8.6%

60+ minutes late

Delay when late

70 min

Average, when 15+ min late

Flights analyzed

17,017

6 carriers

ORD → IAH arrives on time 77.0% of the time; the return trip, IAH → ORD, arrives on time 76.9% of the time.

ORD → IAH spends 35.2 minutes on the ground on a 925-mile trip: 24.5 minutes from pushback to wheels-up at ORD and 10.7 minutes from touchdown to gate at IAH.

Source: US DOT Bureau of Transportation Statistics · Data covering July 2023 – July 2026

Why ORD → IAH flights are cancelled

July 2023 – July 2026

ORD → IAH cancelled 224 of 17,017 scheduled flights — about 1 in every 76. The reason filed most often was extreme weather, 61.6% of the cancellations coded on this route — about 1 in every 123 scheduled flights.

Share of cancellations

Weather61.6%

Airline27.7%

Air traffic10.7%

Security0.0%

Of 224 cancelled departures carrying a reason code.

What each reason means

Extreme weather1 in 123

Conditions the carrier judged severe enough to stop the flight: a blizzard, a hurricane, a line of thunderstorms.

138 cancellations, 61.6% of the total.

The airline1 in 274

Crew, maintenance, aircraft cleaning, baggage or fueling: what BTS counts as within the carrier’s own control.

62 cancellations, 27.7% of the total.

The air traffic system1 in 709

Airport capacity, air traffic control flow programs, heavy traffic and ordinary bad weather. A system decision, not the airline’s.

24 cancellations, 10.7% of the total.

Security—

A terminal evacuation, a security breach, screening equipment failure, or screening queues over 29 minutes.

0 cancellations, 0.0% of the total.

Reason codes are the operating airline’s own filing with US DOT, not an independent finding of fault. Ordinary bad weather is filed under air traffic, so weather’s full share is larger than its bar.

224 coded cancellations were recorded on ORD → IAH; the section appears from 50.

When it goes wrong

July 2023 – July 2026

One arrival in ten is worse than

51 min late

against a median of 6 min early

Arrived an hour or more late8.6%

Typical delay when late70 min

Cancelled1.32%

Landed somewhere else0.33%

Percentiles over 17,017 operations; cancelled and diverted flights are counted separately.

Will your connection be tight enough?

Layovers at IAH after arriving from ORD.

Connection buffer and chance of missing by layover length, ORD → IAH arrivals
Connection time	Chance of missing	Reads as
30 min	38%	Likely to miss
45 min	22%	High risk
60 min	15%	Some risk
90 min	8.5%	Some risk
120 min	5.3%	Some risk

This is one leg of a connection. Gate changes and the next flight's own schedule matter too. And a connection can fail before delay is even the question — this route cancels 1.32% of the time and diverts 0.33% of the time, which a late arrival never shows up in.

Chance of missing is the share of 16,736 arrivals on this route that landed later than the connection time less 30 minutes to reach the next gate.

The worst tenth of arrivals on this route land at least 51 minutes late (90th-percentile gate arrival delay), over 17,017 operations.

Any other layover length: connection checker.

Best time to fly

ORD → IAH flights departing 5–9 AM arrived on time 87.3% of the time, against 66.0% for 6–9 PM departures, a gap of 21.3 percentage points.

By day and hour

On-time arrival rate for each weekday and scheduled departure hour, in local time at the departure airport (ORD).

Hour of departure matters more than day of the week: hourly averages sit a typical 8.7 points from the route-wide rate, weekday averages 2.0 points.

On-time arrival rate for ORD to IAH by weekday and scheduled departure hour, local time. Each button reads out one slot.
Hour	Monday	Tuesday	Wednesday	Thursday	Friday	Saturday	Sunday
6 AM–7 AM
7 AM–8 AM
8 AM–9 AM
9 AM–10 AM
10 AM–11 AM
11 AM–12 PM
12 PM–1 PM
1 PM–2 PM
2 PM–3 PM
3 PM–4 PM
4 PM–5 PM
5 PM–6 PM
6 PM–7 PM
7 PM–8 PM
8 PM–9 PM
9 PM–10 PM

On-time rate, % · stronger color, fewer on time

50–59
60–69
70–79
80–89
90–99

Fewer than 120 flights, not scored

Source: FlyerIntel analysis of US DOT BTS data · July 2023 – July 2026 · On time is arrival within 15 minutes of schedule. Cells round to whole percentages; the table shows one decimal.

No slot is named best or worst: too few reach 500 flights. Departures before 6 AM and after 10 PM (745 flights) are not drawn: no slot in those hours has enough flights to score.

View as tableHide table

On-time arrival rate (%) with flights beneath, by scheduled departure hour and weekday for ORD to IAH. A dash means fewer than 120 flights, which are not scored.
Hour	Monday	Tuesday	Wednesday	Thursday	Friday	Saturday	Sunday
6 AM–7 AM	87.0% on time168 flights	96.2% on time133 flights	92.5% on time133 flights	89.0% on time148 flights	88.1% on time171 flights	87.4% on time136 flights	89.0% on time157 flights
7 AM–8 AM	89.4% on time221 flights	89.0% on time221 flights	90.3% on time211 flights	84.0% on time234 flights	84.7% on time217 flights	85.1% on time223 flights	85.3% on time227 flights
8 AM–9 AM	87.3% on time184 flights	85.2% on time186 flights	88.3% on time182 flights	78.9% on time192 flights	78.8% on time186 flights	82.8% on time163 flights	86.2% on time191 flights
9 AM–10 AM	78.5% on time137 flights	84.2% on time122 flights	80.2% on time120 flights	81.5% on time124 flights	68.0% on time131 flights	96 flights, too few to score	74.4% on time127 flights
10 AM–11 AM	87.2% on time184 flights	83.3% on time195 flights	85.0% on time195 flights	83.0% on time185 flights	82.9% on time182 flights	85.3% on time179 flights	82.2% on time187 flights
11 AM–12 PM	5 flights, too few to score	10 flights, too few to score	9 flights, too few to score	4 flights, too few to score	12 flights, too few to score	15 flights, too few to score	8 flights, too few to score
12 PM–1 PM	85.5% on time177 flights	85.9% on time171 flights	86.6% on time164 flights	87.9% on time176 flights	73.7% on time172 flights	82.7% on time173 flights	84.5% on time183 flights
1 PM–2 PM	72.3% on time143 flights	91 flights, too few to score	105 flights, too few to score	76.3% on time157 flights	74.8% on time155 flights	79 flights, too few to score	70.4% on time154 flights
2 PM–3 PM	69.2% on time206 flights	74.3% on time206 flights	73.3% on time207 flights	73.4% on time207 flights	69.7% on time203 flights	73.4% on time203 flights	70.1% on time205 flights
3 PM–4 PM	67.4% on time132 flights	118 flights, too few to score	116 flights, too few to score	64.8% on time125 flights	65.1% on time126 flights	69.7% on time135 flights	69.2% on time134 flights
4 PM–5 PM	66.4% on time122 flights	109 flights, too few to score	118 flights, too few to score	76.6% on time125 flights	69.6% on time127 flights	113 flights, too few to score	62.6% on time126 flights
5 PM–6 PM	70.4% on time130 flights	72.5% on time135 flights	76.6% on time139 flights	119 flights, too few to score	73.0% on time126 flights	83.3% on time123 flights	77.2% on time126 flights
6 PM–7 PM	95 flights, too few to score	97 flights, too few to score	97 flights, too few to score	96 flights, too few to score	95 flights, too few to score	115 flights, too few to score	96 flights, too few to score
7 PM–8 PM	106 flights, too few to score	105 flights, too few to score	101 flights, too few to score	101 flights, too few to score	99 flights, too few to score	88 flights, too few to score	104 flights, too few to score
8 PM–9 PM	64.5% on time192 flights	69.2% on time166 flights	64.2% on time164 flights	58.1% on time194 flights	56.4% on time199 flights	68.6% on time171 flights	59.3% on time197 flights
9 PM–10 PM	67.4% on time195 flights	73.3% on time149 flights	70.1% on time168 flights	61.4% on time214 flights	67.5% on time218 flights	66.0% on time162 flights	67.5% on time216 flights

By departure window

5–9 AM87.3%

9 AM–12 PM81.5%

12–3 PM76.8%

3–6 PM71.3%

6–9 PM66.0%

9 PM–5 AM67.4%

By departure hour

12 AM

3 AM

6 AM

9 AM

12 PM

3 PM

6 PM

9 PM

Why ORD → IAH runs late

July 2023 – July 2026

Late-arriving aircraft40.2%

the inbound aircraft was late, so this flight started late

The airline26.8%

crew, maintenance, boarding and fueling, all within the carrier’s control

Air traffic control26.4%

airspace and airport capacity, including weather-driven flow control

Weather6.5%

weather severe enough to stop this flight specifically

Security<0.1%

screening or terminal security incidents

Share of the delay minutes US DOT attributed to each cause for ORD → IAH. Only delays of 15 minutes or more are attributed.

Late-arriving aircraft is the largest cause on ORD → IAH, at 40.2%: flights here mostly leave late because the plane came in late, and the day shows it: 5–9 AM departures arrived on time 87.3% of the time and 6–9 PM departures 66.0%.

How this route holds up in bad weather

July 2023 – July 2026

The harder-hit end is the one the flight leaves from, where a cancellation keeps it from departing at all. Bad weather cancels 5.5 times the normal rate at ORD against 3.4 times at IAH. Cancelled in bad weather against normal hours: ORD 6.5% against 1.2%, IAH 4.1% against 1.2%. Flights that did leave ORD in bad weather arrived on time 55.7% of the time, against 77.1% in normal hours.

Bad weather and normal hours at the airports

Scheduled departures, July 2023 – July 2026

Departures from ORD and IAH in hours of bad weather and in normal hours
Departures from	ORD	IAH
Cancelled in bad weather	6.5%	4.1%
Cancelled in normal hours	1.2%	1.2%
Arrived on time, bad weather	55.7%	63.8%
Arrived on time, normal hours	77.1%	78.6%
Departures in bad weather	104,455	28,922

Of the carriers on this route, United Airlines (3.5% cancelled against 7.4% for the other carriers at ORD) cancelled the fewest departures from ORD in bad weather and Envoy Air (8.6% cancelled against 6.9% for the other carriers at ORD) the most.

This route’s airlines in bad weather at ORD

All departures from ORD

Cancellation rates in bad weather at ORD for the airlines that fly ORD to IAH, against the other carriers at ORD in the same months
Airline	Bad-weather departures	Cancelled	Other carriers
United Airlines	31,269	3.5%below the others	7.4%
Frontier Airlines	1,047	6.0%about level	7.5%
American Airlines	17,789	5.4%below the others	6.7%
Spirit Airlines	2,378	4.8%about level	5.5%
Republic Airways	9,471	8.1%above the others	6.5%
Envoy Air	14,228	8.6%above the others	6.9%

These are airport figures, not route figures: every scheduled departure from ORD and IAH, to any destination, in hours the weather report called bad. The airline rows count each carrier’s departures from ORD on every route.

Weather source and limits. In full: ORD (airlines), IAH, What Weather Costs Each Airport, Who Cancels More When the Weather Turns, Airports That Change Places When Weather Turns.

Airlines on this route

Carriers with at least 200 flights, by the airline that operated each one.

Airlines on this route
Carrier	Flights	On time	Cancelled	Median delay	Severe
United Airlines	11,764	79.8%	0.91%	-7 min	6.7%
American Airlines	2,171	67.3%	1.98%	-3 min	14.2%
Spirit Airlines	1,318	70.7%	2.58%	-4 min	14.4%
Envoy Air	686	75.9%	1.31%	-9 min	8.0%
Republic Airways	581	74.9%	2.58%	-8 min	10.3%
Frontier Airlines	490	73.8%	3.27%	-4 min	13.1%

United Airlines flew 69.2% of the 17,010 flights listed. Frontier Airlines cancelled 3.27% of its flights here against 0.91% for United Airlines.

United Airlines arrived on time 12.5 percentage points more often than American Airlines on this route.

Flights on this route

Flight numbers with at least 600 operations here and still on the schedule.

Flights on this route
Flight	Scheduled	Operations	On time
UA2665 United Airlines	9:15 PM	889	71.8%

Weekly and seasonal patterns

By day of week

Mon76.8%

Tue80.2%

Wed79.3%

Thu76.1%

Fri73.8%

Sat77.6%

Sun75.5%

Tuesday is historically the most reliable day and Friday the least, a gap of 6.4 percentage points.

By month

Jan

Feb

Mar

Apr

May

Jun

Jul

Aug

Sep

Oct

Nov

Dec

July is historically the weakest month and February the strongest, a spread of 17.5 percentage points.

Reliability over time

July 2023 – July 2026

24

25

26

Over the most recent 12 months (2025-08 to 2026-07), on-time arrivals averaged 76.1% against 77.0% in the 12 months before — broadly unchanged.

Data and methodology

Calculated by FlyerIntel from 17,017 ORD → IAH flight records from the US DOT Bureau of Transportation Statistics, covering July 2023 – July 2026. Late means 15 or more minutes past scheduled arrival; cancelled and diverted flights are left out of on-time rates.

Full methodology · Data sources · Report a problem

Analysis last recomputed September 26, 2026

ORD airport IAH airport Return direction IAH → ORD

ORD→IAH

Right now

Route reliability

Why ORD → IAH flights are cancelled

Share of cancellations

What each reason means

When it goes wrong

Will your connection be tight enough?

Best time to fly

By day and hour

By departure window

By departure hour

Why ORD → IAH runs late

How this route holds up in bad weather

Bad weather and normal hours at the airports

This route’s airlines in bad weather at ORD

Airlines on this route

Flights on this route

Weekly and seasonal patterns

By day of week

By month

Reliability over time

Data and methodology