Carrier route record

YXIAH→ORD

Republic Airways · Houston to Chicago

Flights: 357
Period: July 2025 to June 2026
Share of route: 6%
Carriers: 8

Historical statistics for July 2025 to June 2026, not live status. For today’s flights, check with Republic Airways.

Republic on IAH to ORD sits in the middle of the pack with a C−. About seven flights in ten arrive on time by the DOT's definition, 6 points worse than the national rate of 77.6%. The late ones land a little over an hour behind schedule. That rests on 357 flights. The strongest carrier on the route with a full sample, United Airlines, flew 4,007 at 78.2% on time.

The national on-time rate over the same period is 77.6%, so Republic on IAH to ORD runs 6 points behind the country as a whole. Across a thousand flights that is about 59 extra late arrivals.

On time

71.7%

Arrivals under 15 minutes late, of 339 completed flights

Avg delay

80 min

Across delayed arrivals only, not all flights

Cancelled

3.64%

National rate is 1.81%

Whole route

74.8%

Every carrier on IAH to ORD, 6,080 flights

These figures cover 357 flights between July 2025 and June 2026. Beyond the headline rate, 14.7% of arrivals land a full hour or more behind schedule. That is the number that wrecks a connection, and it is not visible in an on-time percentage alone.

Carrier by carrier

Republic against every carrier on IAH to ORD

Republic flew 357 of the 6,080 flights on IAH to ORD, about 6% of it. Its 71.7% on time is 3 points worse than the route as a whole, which runs 74.8%. Ranked by on-time rate it is number three of eight carriers on the route, where the range runs from United at 78.2% to PSA at 50.0%. Five of those carriers flew fewer than 365 flights here, so treat their positions as rough.

The choice of carrier is not cosmetic here. United Airlines arrives on time 78.2% of the time; American Airlines manages 67.1%. Sample sizes sit next to every figure, because a two-point gap across 798 flights means less than a ten-point one.

On-time performance by carrier on IAH to ORD
Airline	Flights	On time	Avg delay	Cancelled	Grade
United Airlines	4,007	78.2%	70 min	0.60%	B+
Envoy Airthin sample	359	72.8%	62 min	1.11%	C
Republic Airways (this page)thin sample	357	71.7%	80 min	3.64%	C−
American Airlines	798	67.1%	122 min	3.51%	C−
Spirit Airlinesthin sample	305	66.0%	70 min	4.59%	C−
Frontier Airlinesthin sample	248	61.8%	130 min	2.82%	D
SkyWest Airlinesthin sample	2	50.0%	38 min	0.00%	F+
PSA Airlinesthin sample	4	50.0%	156 min	0.00%	F+

American Airlines cancels 3.5% of what it schedules here, the highest in the table. A cancelled flight never appears in an on-time rate, so read that column alongside the punctuality one rather than after it.

Departure window

When Republic runs best on this route

Departure time matters more here than the choice of carrier. The gap between the best and worst window is 14 points, against 11 points between the best and worst carrier. Each bar is the on-time rate for flights scheduled inside that window.

5am–8am—
8am–11am7 flights—
11am–2pm151 flights74.5%
2pm–5pm92 flights77.3%
5pm–8pm105 flights62.9%
8pm–5am2 flights—

Scale runs 55% to 85%. Rows with fewer than 30 flights show a dash.

The 5pm–8pm window is where this operation falls apart: 62.9% on time, against 77.3% for the 2pm–5pm slot. By evening the aircraft flying these rotations have absorbed a full day of small delays and there is no slack left to recover in. The 11am–2pm window is the busiest, with 151 flights scheduled in it.

Across the year

Republic on IAH to ORD through the year

Jul–Sep 202589 flights66.7%
Oct–Dec 202598 flights71.3%
Jan–Mar 202647 flights87.0%
Apr–Jun 2026123 flights69.6%

Scale runs 60% to 90%. Rows with fewer than 30 flights show a dash.

Monthly volumes are too low here to break the year into twelve reliable readings. What the twelve-month total says is 71.7% on time across 357 flights.

Republic on IAH to ORD did not run the same all year. Its best quarter was Jan–Mar 2026 at 87.0% on time and its weakest Jul–Sep 2025 at 66.7%, a swing of 20 points on roughly 89 flights a quarter. The twelve-month rate averages over that, so if you are flying in a weak quarter the quarter's own figure is the better guide.

Across the week, Saturday is the strongest day at 82.5% on time and Tuesday the weakest at 64.4%. 18 points is a smaller lever than departure hour, but it is free.

Delay causes

Why Republic runs late on this route

One category carries most of the weight here. Late-arriving aircraft accounts for 51% of the 7,639 delay minutes carriers reported, and the remaining four split what is left. The split is by minutes rather than by flights, so a few very long delays count for as much as many short ones.

Late-arriving aircraft
51%
National Airspace System
32%
Carrier
12%
Extreme weather
4%
Security
0%

51% of delay minutes trace back to a late-arriving aircraft, meaning the plane was already behind before it got here. That is a cascade, and cascades start small and grow through the day. Across 7,639 reported delay minutes here, that single category outweighs weather by 11 to one. It is the strongest argument for booking the first departure of the morning, when the aircraft has been sitting at the gate overnight with nothing to inherit. The split is drawn from 7,639 reported delay minutes.

Cancellations run at 3.64%, against 1.81% nationally. That is roughly one flight in 25 cancelled outright. A cancelled flight is invisible in every on-time figure on this page, so the punctuality numbers above describe only the flights that actually operated.

Connections and stage length

What a delay here costs

For anyone connecting, the number to weigh is not the on-time rate but the tail behind it. 14.7% of arrivals land a full hour or more behind schedule, against 8.1% nationally. A 45-minute layover does not survive that, and no amount of walking quickly changes it. Ninety minutes is the honest minimum here, and two hours if the onward flight is on a separate ticket.

The 925 miles between these two airports put this in the middle of the US network, around two and a half to three hours of block time. That is enough cruise to absorb a ten-minute late pushback and not enough to absorb thirty. It is also long enough that the aircraft usually flies three or four legs a day rather than six, which slows how fast delay compounds.

The return leg is a different operation and performs like one: it runs 76.3% on time across 359 flights, 5 points above this direction. Departure banks, aircraft rotations and the congestion at each end all differ, so scoring the two directions together would average away a real 5 points of difference.

One caution: this is a thin sample. 357 flights over twelve months is enough to clear this site's floor but not enough to pin the rate down tightly, and a single bad week moves it by more than a point. Treat the grade as a rough reading.

What to do with this

Booking Republic on IAH to ORD

Put together: the delay figures matter less here than the 3.64% cancellation rate. A late arrival costs you a little over an hour; a cancelled flight costs you the day. Book the 2pm–5pm departure so there is still a schedule behind you if it goes wrong, and treat a same-day connection as optimistic. 339 completed flights over 12 months sit behind that.

Where to go next

Source: US DOT Bureau of Transportation Statistics, on-time performance data, July 2025 to June 2026. Last updated 15 September 2026; recomputed monthly. How this data is collected.

Key figures