Carrier route record
UAORD→PIT
United Airlines · Chicago to Pittsburgh
- Flights
- 1,318
- Period
- September 2025 to August 2026
- Share of route
- 33%
- Carriers
- 5
Historical statistics for September 2025 to August 2026, not live status. For today’s flights, check with United Airlines.
United on ORD to PIT sits in the middle of the pack with a C. Close to three flights in four arrive on time by the DOT's definition, 3 points worse than the national rate of 77.3%. The late ones land a little over an hour behind schedule. That rests on 1,318 flights. The strongest carrier on the route with a full sample, Republic Airways, flew 1,722 at 80.3% on time.
The US average over the same twelve months is 77.3%, so there is little to separate United on ORD to PIT from the country as a whole. The variation that matters here is internal: which carrier, and what time of day.
Key figures
On time
74.2%
Arrivals under 15 minutes late, of 1,297 completed flights
Avg delay
68 min
Across delayed arrivals only, not all flights
Cancelled
1.37%
National rate is 1.89%
Whole route
73.6%
Every carrier on ORD to PIT, 4,029 flights
These figures cover 1,318 flights between September 2025 and August 2026. Beyond the headline rate, 9.6% of arrivals land a full hour or more behind schedule, against 8.3% nationally.
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Carrier by carrier
United against every carrier on ORD to PIT
United flew 1,318 of the 4,029 flights on ORD to PIT, about 33% of it. Its 74.2% on time is about level with the route as a whole at 73.6%. Ranked by on-time rate it is number three of five carriers on the route, where the range runs from Republic at 80.3% to American at 54.2%. Two of those carriers flew fewer than 365 flights here, so treat their positions as rough.
The choice of carrier is not cosmetic here. Republic Airways arrives on time 80.3% of the time; American Airlines manages 54.2%. Sample sizes sit next to every figure, because a two-point gap across 616 flights means less than a ten-point one.
| Airline | Flights | On time | Avg delay | Cancelled | Grade |
|---|---|---|---|---|---|
| Republic Airways | 1,722 | 80.3% | 85 min | 2.56% | B |
| Envoy Airthin sample | 138 | 80.0% | 68 min | 2.17% | B |
| United Airlines (this page) | 1,318 | 74.2% | 68 min | 1.37% | C |
| SkyWest Airlinesthin sample | 235 | 68.3% | 63 min | 3.40% | C− |
| American Airlines | 616 | 54.2% | 100 min | 3.08% | F− |
American Airlines cancels 3.1% 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.
Flight by flight
United flight numbers on ORD to PIT
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Departure window
When United runs best on this route
Departure time matters more here than the choice of carrier. The gap between the best and worst window is 25 points, against 26 points between the best and worst carrier.
- 5am–8am299 flights87.4%
- 8am–11am332 flights77.8%
- 11am–2pm—
- 2pm–5pm326 flights71.2%
- 5pm–8pm359 flights62.7%
- 8pm–5am2 flights—
Scale runs 55% to 95%. Rows with fewer than 30 flights show a dash.
The 5pm–8pm window is where this operation falls apart: 62.7% on time, against 87.4% for the 5am–8am 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 5pm–8pm window is the busiest, with 359 flights scheduled in it.
Across the year
United on ORD to PIT through the year
August is the worst month at 65.6% on time, 20 points below September, the best at 86.0%. Summer afternoon convection and peak-season schedules land on the same weeks every year, so this is a pattern you can book around rather than a run of bad luck. August was the busiest month here, with 124 flights.
Across the week, Tuesday is the strongest day at 82.3% on time and Saturday the weakest at 68.6%, a spread of 14 points.
Arrival by arrival
How late United on ORD to PIT runs when it is late
The 335 late arrivals split 120 under half an hour, 91 between 30 and 60 minutes, and 124 an hour or more.
- 15+ min early272 flights21.0%
- Within 15 min690 flights53.2%
- 15–29 min late120 flights9.3%
- 30–59 min late91 flights7.0%
- 1–2 hours late75 flights5.8%
- 2+ hours late49 flights3.8%
Scale runs 0% to 100%.
Share of 1,297 completed flights by arrival against schedule.
Time lost at the gate mostly stays lost. Of 271 departures that left 15 minutes late or more, only 30 made it up before arrival. In the other direction, 94 flights left on time yet arrived 15 minutes late or more, so that delay built up after pushback: in the air, in a holding pattern or on the ground at PIT.
The worst days
Worst days for United on ORD to PIT
The latest arrival of the period was on 4 May 2026, 8 hours 24 minutes behind schedule; most of its delay minutes were filed as extreme weather. On three of the five worst days the largest share was filed as a late-arriving aircraft.
| Date | Arrived late by | Largest filed cause |
|---|---|---|
| 4 May 2026 | 8 hours 24 minutes | Extreme weather |
| 30 November 2025 | 6 hours 14 minutes | Carrier |
| 7 December 2025 | 5 hours 29 minutes | Late-arriving aircraft |
| 3 July 2026 | 5 hours 27 minutes | Late-arriving aircraft |
| 9 August 2026 | 5 hours 17 minutes | Late-arriving aircraft |
Delay causes
Why United runs late on this route
Late-arriving aircraft accounts for 42% of the 23,000 delay minutes carriers reported here, and the remaining four split what is left.
- 42%Late-arriving aircraft
- 31%Carrier
- 18%National Airspace System
- 9%Extreme weather
42% of delay minutes trace back to a late-arriving aircraft, meaning the plane was already behind before it got here. Across 23,000 reported delay minutes here, that single category outweighs weather by 4 to one. The split is drawn from 22,922 reported delay minutes.
The practical consequence: the 5am–8am departure is the one that starts clean. Its aircraft has no earlier leg to be late from, which is exactly why that window shows 87.4% on time here.
Cancellations sit at 1.37% against a national 1.89%, which is ordinary. Diversions add another 0.23%.
Connections and stage length
What a delay here costs
9.6% of arrivals land a full hour or more behind schedule, against 8.3% nationally. Ninety minutes is the honest minimum for a connection here, and two hours if the onward flight is on a separate ticket.
At 413 miles this is a short hop, and stage length matters more than it looks. A flight this short spends under two hours in the air, which leaves almost nothing to claw back a late pushback with. Delay here is decided on the ground, in the turn, which is why the 5am–8am window matters as much as it does.
The return leg runs 76.1% on time across 1,317 flights, within 2 points of this direction. The two legs are scored separately because they usually differ; on this city pair they happen not to.
The sample behind these figures is 1,318 flights, enough that the headline rate is stable to within roughly a point. The hour-block and month splits divide that further, so read the thinner bars with more caution than the headline.
What to do with this
Booking United on ORD to PIT
Put together: the calendar is the biggest lever here, not the carrier or the hour. September runs 86.0% on time and August 65.6%, a swing of 20 points. If the dates move at all, move them out of August before you think about anything else. 1,297 completed flights over 12 months sit behind that.
Related
Where to go next
- ORD to PIT, every carrier
- United on PIT to ORD, the return leg
- Republic Airways on ORD to PIT80.3%
- Envoy Air on ORD to PIT80.0%
- SkyWest Airlines on ORD to PIT68.3%
- American Airlines on ORD to PIT54.2%
- United Airlines network-wide record
- Chicago O'Hare International (ORD) delay statistics
- Pittsburgh International (PIT) delay statistics
- Same route, different airline: where the carrier you pick matters most
- Why the first flight of the morning is statistically safest
Source: US DOT Bureau of Transportation Statistics, on-time performance data, September 2025 to August 2026. Last updated ; recomputed monthly. How this data is collected.