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Route · PWM → IAD · 2020–2025 BTS data

Portland to Washington

According to PlainFlights' route traffic ranking (BTS On-Time Performance total flights), PWM to IAD (Portland to Washington) ranks #3374 of 4927 tracked domestic routes by total flights (most flights = #1).

Data updated 2026-06-13

86.4%
On-time
+7.4 pts
vs US avg
85 min
Delay when late
2,820
Flights
#3374 of 4927
Corpus placement

Cancelled

2.0%

Best Month

Sep 2024 93%

Worst Month

Jul 2023 75%

Distance

493 mi

Carriers

8

Monthly Performance

Recent 24 months of route data.

Period Flights Delayed Cancelled Diverted Carriers
Oct 2025 96 15 0 0 YX
Sep 2025 94 15 1 0 YX
Aug 2025 109 15 0 0 YX,UA
Jul 2025 123 22 12 1 UA,YX
Jun 2025 126 26 1 0 UA,YX
May 2025 136 18 2 0 YX
Mar 2025 30 2 0 0 YX
Dec 2024 46 8 0 0 UA,YX
Nov 2024 47 6 0 0 YX,UA
Oct 2024 59 5 0 0 UA,YX
Sep 2024 85 6 0 0 YX,UA
Aug 2024 93 14 5 2 YX
Jul 2024 93 9 3 0 YX
Jun 2024 90 7 3 0 YX
May 2024 44 2 1 0 YX
Jan 2024 40 7 3 0 YX
Dec 2023 42 4 0 0 YX
Nov 2023 30 2 0 0 YX
Oct 2023 59 5 0 0 YX,UA
Sep 2023 65 13 3 0 UA,YX
Aug 2023 92 9 0 0 UA,YX
Jul 2023 61 15 0 0 YX,UA
Jun 2023 80 16 2 0 UA,YX
May 2023 50 2 0 0 YX

PWM–IAD seasonal on-time pattern

Best: March (93.3%) · weakest: April (70.0%)

60%70%80%90%100% JanMarAprMayJunJulAugSepOctNovDec 89.4%

Strongest calendar month

March

93.3% on-time · ~30 flights/mo

Busiest calendar month

May

~77 flights/mo avg

Weakest calendar month

April

70.0% on-time · ~30 flights/mo

Cancellation Rate

2.0%

36 of 1,790 flights

Diversion Rate

0.2%

3 of 1,790 flights

Explore origin & destination

On-time and delay data for the airports this route connects.

PWM - Portland

Full on-time, delay-cause, and seasonal performance for Portland, ME.

PWM on-time profile

IAD - Washington

Full on-time, delay-cause, and seasonal performance for Washington, DC.

IAD on-time profile

Compare the two airports

See PWM and IAD side by side on delays, cancellations, and reliability.

Compare PWM vs IAD

Origin-hub reliability standing

Among PWM's stronger departures

PWM → IAD posts a 86.4% on-time rate, landing in the ≥85% band with 2 of 12 BTS-tracked routes leaving Portland. The same hub also shows 9 mid-band and 1 challenged departures · fleet-wide on-time rank #800 of 4927 (highest on-time = #1).

What the Data Says About PWM to IAD

Portland to Washington (PWM to IAD) is one of the more dependable pairings in the BTS On-Time Performance dataset: a 86.4% on-time rate across 2,820 flights, with delays that do happen averaging 84.8 minutes. The corridor runs roughly 493 miles and is served by 8 carriers. Over the most recent 24 months, 36 of 1,790 flights were cancelled (2.0%) and 3 diverted (0.2%).

The monthly split is wide on this route: Sep 2024 posted the strongest performance at 93% on-time, while Jul 2023 came in at just 75% - a 18-point swing worth factoring into travel timing.

On the multi-year calendar, PWM–IAD peaks in March at 93.3% on-time while May carries the heaviest traffic (~77 flights per month) ; the softest month is April at 70.0%, a 23.3-point swing that repeats because the corridor's weather and holiday mix stays stable year to year.

Frequently Asked Questions

Where does PWM to IAD rank among US routes by traffic? ▼
According to PlainFlights' route traffic ranking, PWM to IAD ranks #3374 of 4927 tracked domestic routes by total flights (most flights = #1). That ordinal matches our busiest-routes listing (total_flights DESC). See /methodology#corpus-placement for the exact sort basis.
How often are flights delayed from PWM to IAD? ▼
Flights from Portland to Washington have a 86.4% on-time rate based on 2,820 flights. The average delay is 84.8 minutes. The best recent month was Sep 2024 with 93% on-time.
What is the cancellation rate for PWM to IAD? ▼
Over the last 24 months, 2.0% of flights on this route were cancelled (36 of 1,790 flights) and 0.2% were diverted.
How far is the flight from PWM to IAD? ▼
The flight distance from Portland (PWM) to Washington (IAD) is approximately 493 miles. This route is served by 8 carriers.
When is the best time to fly from PWM to IAD? ▼
The best recent month for on-time performance was Sep 2024 (93% on-time). The worst was Jul 2023 (75% on-time). Consider booking during months with historically better performance.

Airports on this route

PWM Airport

Portland
IAD Airport

Washington
Data source

Data Source: Bureau of Transportation Statistics (BTS), On-Time Performance Data. Statistics reflect cumulative performance across all available reporting periods.

Read our methodology - how this data is sourced, computed, and verified.

Using PWM–IAD data

PWM–IAD runs 7.4 pts above the national 79% average; the remaining risk is month-to-month swing and carrier mix, not a weak headline rate.

  • Compare PWM and IAD airport profiles: delay causes and top routes differ even on the same corridor. PWM airport
  • If your dates flex, March (93.3% on-time) beats April (70.0%) on this corridor. Seasonal chart
  • 4 other routes post a similar 86.4% on-time rate; compare before you commit to this pairing. Similar routes

On-time rate reflects the BTS historical average across all reporting carriers on this origin–destination pair, not any single flight or booking recommendation.

Data sourced from U.S. Department of Transportation Bureau of Transportation Statistics (BTS) On-Time Performance data. See our methodology for details. Retrieved and formatted by PlainFlights

Every figure on PlainFlights is rendered directly from BTS On-Time Performance data, no number is typed in by an editor. This page aggregates this specific route's on-time performance and monthly trend, live from the dataset. See our editorial standards & corrections policy, the methodology behind these numbers, or report a data error.