Portland International Jetport (PWM) Delays and On-Time Departures
Portland, ME · ranked 119th of 333 airports for on-time departures
Data through July 2026 · Last updated October 18, 2026
Over the last 12 months, Portland (PWM) had 10,925 scheduled departures and 82.0% of them left on time (US average 77.4%).
That ranks 119th of 333 US airports tracked on this site, with 2.6% of departures cancelled.
Among airlines at Portland (PWM), United Airlines left on time most often (87.2%).
Over 24 months, Wednesday was the most reliable day (86% on time) and July the worst month (72%).
Best time of day to fly out of Portland (PWM)
On-time departure % by scheduled departure hour (local time), last 24 months.
Show the numbers
| Departure hour | On time | Cancelled | Flights |
|---|---|---|---|
| 5am–6am | 91.7% | 2.5% | 2,304 |
| 6am–7am | 91.1% | 2.4% | 3,221 |
| 7am–8am | 92.2% | 1.9% | 1,392 |
| 8am–9am | 91.1% | 1.1% | 442 |
| 9am–10am | 92.5% | 1.4% | 500 |
| 10am–11am | 85.8% | 1.9% | 737 |
| 11am–12pm | 85.9% | 1.3% | 1,393 |
| 12pm–1pm | 80.3% | 1.1% | 2,362 |
| 1pm–2pm | 76.3% | 1.4% | 1,319 |
| 2pm–3pm | 75.8% | 2.9% | 1,558 |
| 3pm–4pm | 75.3% | 3.0% | 1,681 |
| 4pm–5pm | 77.0% | 2.1% | 2,089 |
| 5pm–6pm | 68.8% | 4.2% | 1,902 |
| 6pm–7pm | 65.4% | 3.0% | 668 |
| 7pm–8pm | 77.1% | 4.6% | 734 |
| 8pm–9pm | 71.3% | 9.8% | 143 |
| 9pm–10pm | Limited data | 25 | |
| 10pm–11pm | Limited data | 5 | |
Airlines at PWM ranked by on-time departures
Last 12 months. Airlines with fewer than 30 departures are marked “limited data”.
| Airline | On-time departures | On-time arrivals | Cancelled | Departures |
|---|---|---|---|---|
| United Airlines | 87.2% | 78.8% | 1.5% | 854 |
| Republic Airways | 86.1% | 83.4% | 4.0% | 3,507 |
| Envoy Air | 83.6% | 81.9% | 4.1% | 196 |
| Southwest Airlines | 80.9% | 82.3% | 0.8% | 1,655 |
| American Airlines | 79.3% | 78.9% | 1.4% | 1,963 |
| Delta Air Lines | 79.0% | 82.3% | 1.1% | 1,196 |
| JetBlue | 78.2% | 78.7% | 3.2% | 431 |
| PSA Airlines | 76.8% | 75.9% | 6.5% | 682 |
| SkyWest Airlines | 75.7% | 67.3% | 2.8% | 436 |
| Frontier Airlines | Limited data | 5 | ||
80%+ good 70–79.9% fair <70% poor
Best day to fly out of PWM
On-time departures by day, 24 months.
Best month to fly out of PWM
On-time departures by month, 24 months.
Holiday travel at Portland (PWM)
On-time departures during holiday periods compared with all other days, last 24 months.
| Period | On-time departures | vs other days | Cancelled | Flights |
|---|---|---|---|---|
| Thanksgiving week (Tue before to Mon after) | 83.1% | -1.5 pts | 1.5% | 330 |
| Christmas & New Year (Dec 20 - Jan 3) | 79.7% | -5.0 pts | 1.3% | 628 |
| Summer peak (Jun 15 - Aug 15) | 73.5% | -11.1 pts | 4.5% | 5,142 |
| All other days | 84.7% | — | 1.8% | 16,375 |
Monthly on-time departure trend at PWM
On-time departure % each month, with the 12-month US average for reference.
Routes from Portland (PWM)
Every route from PWM with its own page, by number of flights (last 12 months, on-time arrivals).
| To | On time | Cancelled | Flights |
|---|---|---|---|
| PWM → Chicago (ORD) | 78.3% | 3.5% | 1,494 |
| PWM → Baltimore (BWI) | 82.9% | 0.9% | 1,342 |
| PWM → New York (LGA) | 82.0% | 4.5% | 1,183 |
| PWM → Washington (DCA) | 74.6% | 3.7% | 1,159 |
| PWM → Newark (EWR) | 83.4% | 3.7% | 1,082 |
| PWM → Charlotte (CLT) | 82.0% | 1.1% | 708 |
| PWM → Washington (IAD) | 86.5% | 2.3% | 686 |
| PWM → Philadelphia (PHL) | 79.7% | 3.4% | 676 |
| PWM → Atlanta (ATL) | 81.5% | 1.1% | 642 |
| PWM → Detroit (DTW) | 79.7% | 1.0% | 613 |
| PWM → New York (JFK) | 80.5% | 4.8% | 398 |
| PWM → Denver (DEN) | 71.4% | 0.0% | 214 |
| PWM → Nashville (BNA) | 73.2% | 0.6% | 159 |
| PWM → Chicago (MDW) | 87.3% | 0.0% | 151 |