Route profile
PDX→ORD
Flight reliability, delays and best times to fly from Portland to Chicago, 1,739 miles.
Right now
Weather conditions are strongly associated with delays and cancellations.
Aviation weather is not currently a factor.
Route reliability
July 2023 – July 2026
Better than 65% of comparable major US routes (4,598 compared)
Calculated from 7,509 flights. How this is calculated
PDX → ORD arrives on time 80.9% of the time; the return trip, ORD → PDX, arrives on time 75.1% of the time, a 5.9-point gap between the two directions of the same city pair.
PDX → ORD spends 32.6 minutes on the ground on a 1,739-mile trip: 14.7 minutes from pushback to wheels-up at PDX and 17.8 minutes from touchdown to gate at ORD.
Source: US DOT Bureau of Transportation Statistics · Data covering July 2023 – July 2026
What stands out
Every day of the week performs about the same on this route, steadier than 92% of 4,467 comparable routes.
83.5% on time on the best day (Tuesday) against 78.9% on the worst (Thursday).
Source: FlyerIntel analysis of US DOT BTS data · July 2023 – July 2026 · Ranked against every other route with the same kind of figure and at least 4,467 in the comparison.
What sets this route apart
Where PDX to ORD differs most from similar routes by hour, weekday, month and airline, July 2023 – July 2026.
PDX to ORD is at its best against routes of similar length for flights scheduled at 10 PM: 84.6% arrive on time, 8.9 points ahead of the 75.7% those routes manage at that hour. Against all other routes the gap is 13 points.
PDX to ORD struggles most at 12 AM: 72.4% of its flights scheduled then arrive on time, 6.6 points behind the 79.0% on routes of similar length at the same hour. Against all other routes the gap is 9.2 points.
PDX to ORD holds up on Mondays better than routes of similar length do: 82.0% on time to their 77.2%, a 4.8 points lead. Against all other routes the gap is 4.8 points.
March is kinder to PDX to ORD than to routes of similar length: 88.0% on time against 78.3%, 9.7 points better. Against all other routes the gap is 10.1 points.
United Airlines does better on PDX to ORD than on its routes of similar length: 84.6% on time here, 80.2% there, 4.4 points apart. Against all other routes the gap is 4.7 points.
PDX to ORD against comparable routes
July 2023 – July 2026| Measure | This route | Compared with | Them | Gap | Flights behind it |
|---|---|---|---|---|---|
| Hour: 10 PM departures | 84.6% | routes of similar length | 75.7% | +8.9 pts | 344 here, 32,172 there |
| Hour: 12 AM departures | 72.4% | routes of similar length | 79.0% | −6.6 pts | 185 here, 13,264 there |
| Weekday: Monday | 82.0% | routes of similar length | 77.2% | +4.8 pts | 1,058 here, 204,648 there |
| Month: March | 88.0% | routes of similar length | 78.3% | +9.7 pts | 418 here, 112,756 there |
| Airline: United Airlines | 84.6% | routes of similar length | 80.2% | +4.4 pts | 4,167 here, 290,272 there |
Each comparison pools the flights of other routes, with this route’s own left out. Similar length means within 15% of this route’s 1,739 miles, with at least 5 such routes. A bucket is set against the most comparable group that has enough flights: similar length, then the same origin (at least 3 routes), then all other routes. Hours, weekdays and months appear only where both sides have 120 completed flights, and airlines where both have 600. The gap must be at least 2 points and 2 standard errors, and only the largest gap each way is kept per measure. These are differences in the flights counted, not causes.
Why PDX → ORD flights are cancelled
July 2023 – July 2026
PDX → ORD cancelled 81 of 7,509 scheduled flights — about 1 in every 93. The reason filed most often was extreme weather, 51.9% of the cancellations coded on this route — about 1 in every 179 scheduled flights.
Share of cancellations
Of 81 cancelled departures carrying a reason code.
What each reason means
Conditions the carrier judged severe enough to stop the flight: a blizzard, a hurricane, a line of thunderstorms.
42 cancellations, 51.9% of the total.
Crew, maintenance, aircraft cleaning, baggage or fueling: what BTS counts as within the carrier’s own control.
38 cancellations, 46.9% of the total.
Airport capacity, air traffic control flow programs, heavy traffic and ordinary bad weather. A system decision, not the airline’s.
1 cancellation, 1.2% of the total.
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.
81 coded cancellations were recorded on PDX → ORD; the section appears from 50.
When it goes wrong
July 2023 – July 2026
33 min late
against a median of 6 min early
Percentiles over 7,509 operations; cancelled and diverted flights are counted separately.
Will your connection be tight enough?
Layovers at ORD after arriving from PDX.
| Connection time | Chance of missing | Reads as |
|---|---|---|
| 30 min | 38% | Likely to miss |
| 45 min | 18% | High risk |
| 60 min | 11% | Some risk |
| 90 min | 5.4% | Some risk |
| 120 min | 3.5% | Low 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 1.08% of the time and diverts 0.55% of the time, which a late arrival never shows up in.
Chance of missing is the share of 7,387 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 33 minutes late (90th-percentile gate arrival delay), over 7,509 operations.
Any other layover length: connection checker.
Best time to fly
PDX → ORD flights departing 5–9 AM arrived on time 85.9% of the time, against 70.4% for 12–3 PM departures, a gap of 15.5 percentage points.
By departure window
By departure hour
- 12 AM: 72.4% on time from 189 flights
- 1 AM to 5 AM: too few flights to score
- 6 AM: 88.8% on time from 246 flights
- 7 AM: 85.5% on time from 2,190 flights
- 8 AM to 9 AM: too few flights to score
- 10 AM: 81.2% on time from 839 flights
- 11 AM: 82.5% on time from 708 flights
- 12 PM: too few flights to score
- 1 PM: 68.0% on time from 400 flights
- 2 PM: 72.8% on time from 680 flights
- 3 PM to 9 PM: too few flights to score
- 10 PM: 84.6% on time from 347 flights
- 11 PM: 81.1% on time from 1,580 flights
Why PDX → ORD runs late
July 2023 – July 2026
crew, maintenance, boarding and fueling, all within the carrier’s control
the inbound aircraft was late, so this flight started late
airspace and airport capacity, including weather-driven flow control
weather severe enough to stop this flight specifically
screening or terminal security incidents
Share of the delay minutes US DOT attributed to each cause for PDX → ORD. Only delays of 15 minutes or more are attributed.
Airlines on this route
Carriers with at least 200 flights, by the airline that operated each one.
| Carrier | Flights | On time | Cancelled | Median delay | Severe |
|---|---|---|---|---|---|
| United Airlines | 4,223 | 84.6% | 0.85% | -8 min | 4.7% |
| American Airlines | 1,619 | 73.4% | 1.24% | -4 min | 9.2% |
| Alaska Airlines | 1,560 | 80.6% | 1.28% | -3 min | 2.7% |
United Airlines flew 57.1% of the 7,402 flights listed.
United Airlines arrived on time 11.2 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.
Weekly and seasonal patterns
By day of week
Tuesday is historically the most reliable day and Thursday the least, a gap of 4.6 percentage points.
By month
- Jan: 84.8%
- Feb: 89.6%
- Mar: 88.0%
- Apr: 81.1%
- May: 79.6%
- Jun: 75.8%
- Jul: 71.9%
- Aug: 81.3%
- Sep: 81.8%
- Oct: 85.5%
- Nov: 86.4%
- Dec: 85.9%
July is historically the weakest month and February the strongest, a spread of 17.7 percentage points.
Reliability over time
July 2023 – July 2026
- July 2023: 76.5% from 219 flights
- August 2023: 85.0% from 215 flights
- September 2023: 86.0% from 180 flights
- October 2023: 90.2% from 183 flights
- November 2023: 88.7% from 133 flights
- December 2023: 90.7% from 140 flights
- January 2024: too few flights to score (107)
- February 2024: too few flights to score (85)
- March 2024: too few flights to score (118)
- April 2024: 89.2% from 187 flights
- May 2024: 76.1% from 239 flights
- June 2024: 81.0% from 281 flights
- July 2024: 72.0% from 297 flights
- August 2024: 84.0% from 261 flights
- September 2024: 86.2% from 198 flights
- October 2024: 91.3% from 196 flights
- November 2024: 89.0% from 146 flights
- December 2024: 89.6% from 144 flights
- January 2025: too few flights to score (111)
- February 2025: too few flights to score (95)
- March 2025: 87.8% from 123 flights
- April 2025: 82.2% from 203 flights
- May 2025: 77.6% from 254 flights
- June 2025: 72.4% from 289 flights
- July 2025: 62.6% from 297 flights
- August 2025: 76.2% from 294 flights
- September 2025: 75.5% from 255 flights
- October 2025: 77.9% from 264 flights
- November 2025: 82.2% from 174 flights
- December 2025: 78.4% from 164 flights
- January 2026: 84.7% from 140 flights
- February 2026: 89.8% from 148 flights
- March 2026: 84.7% from 181 flights
- April 2026: 73.6% from 242 flights
- May 2026: 84.2% from 285 flights
- June 2026: 74.2% from 322 flights
- July 2026: 77.0% from 339 flights
Over the most recent 12 months (2025-08 to 2026-07), on-time arrivals averaged 78.9% against 80.8% in the 12 months before — declining by 1.9 percentage points.
Data and methodology
Calculated by FlyerIntel from 7,509 PDX → ORD 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
Related research: How Long a Layover Needs to Be · Two Airlines on One Route · Best Time of Day to Fly From Major US Airports
Analysis last recomputed