Route profile
SEA→PIT
Flight reliability, delays and best times to fly from Seattle to Pittsburgh, 2,125 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 78% of comparable major US routes (4,598 compared)
Calculated from 1,400 flights. How this is calculated · What counts as on time
SEA → PIT arrives on time 77.8% of the time; the return trip, PIT → SEA, arrives on time 77.0% of the time.
SEA → PIT spends 28.2 minutes on the ground on a 2,125-mile trip: 21.9 minutes from pushback to wheels-up at SEA and 6.3 minutes from touchdown to gate at PIT.
Source: US DOT Bureau of Transportation Statistics · Data covering July 2023 – July 2026
What stands out
Unlike most, it barely matters what time you fly this route, a steadier spread than 93% of 4,023 comparable routes.
84.2% on time for 12–3 PM departures, against 76.3% for 9 PM–5 AM, a narrow gap either way.
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 4,023 in the comparison.
What sets this route apart
Where SEA to PIT differs most from similar routes by hour, weekday, month and airline, July 2023 – July 2026.
SEA to PIT struggles most at 10 PM: 71.2% of its flights scheduled then arrive on time, 9.7 points behind the 80.9% on routes of similar length at the same hour.
SEA to PIT is at its best against routes of similar length for flights scheduled at 1 PM: 84.6% arrive on time, 8.4 points ahead of the 76.2% those routes manage at that hour. Against all other routes the gap is 7.5 points.
SEA to PIT against comparable routes
July 2023 – July 2026| Measure | This route | Compared with | Them | Gap | Flights behind it |
|---|---|---|---|---|---|
| Hour: 10 PM departures | 71.2% | routes of similar length | 80.9% | −9.7 pts | 146 here, 58,402 there |
| Hour: 1 PM departures | 84.6% | routes of similar length | 76.2% | +8.4 pts | 143 here, 44,264 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 2,125 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.
When it goes wrong
July 2023 – July 2026
34 min late
against a median of 2 min early
Percentiles over 1,400 operations; cancelled and diverted flights are counted separately.
Will your connection be tight enough?
Layovers at PIT after arriving from SEA.
| Connection time | Chance of missing | Reads as |
|---|---|---|
| 30 min | 44% | Likely to miss |
| 45 min | 21% | High risk |
| 60 min | 12% | Some risk |
| 90 min | 3.5% | Low risk |
| 120 min | 1.4% | 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 0.57% of the time and diverts 0.36% of the time, which a late arrival never shows up in.
Chance of missing is the share of 1,387 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 34 minutes late (90th-percentile gate arrival delay), over 1,400 operations.
Any other layover length: connection checker.
Best time to fly
SEA → PIT flights departing 12–3 PM arrived on time 84.2% of the time, against 76.3% for 9 PM–5 AM departures, a gap of 7.9 percentage points.
By departure window
By departure hour
- 12 AM to 8 AM: too few flights to score
- 9 AM: 78.7% on time from 379 flights
- 10 AM: 83.7% on time from 172 flights
- 11 AM: 70.9% on time from 281 flights
- 12 PM: too few flights to score
- 1 PM: 84.6% on time from 144 flights
- 2 PM to 9 PM: too few flights to score
- 10 PM: 71.2% on time from 146 flights
- 11 PM: 79.5% on time from 130 flights
Why SEA → PIT 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 SEA → PIT. Only delays of 15 minutes or more are attributed. What the five causes mean
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 |
|---|---|---|---|---|---|
| Alaska Airlines | 1,399 | 77.8% | 0.57% | -2 min | 3.8% |
Flights on this route
Flight numbers with at least 600 operations here and still on the schedule.
| Flight | Scheduled | Operations | On time |
|---|---|---|---|
| AS412 Alaska Airlines | 9:45 AM | 976 | 77.9% |
Weekly and seasonal patterns
By day of week
Monday is historically the most reliable day and Friday the least, a gap of 8.4 percentage points.
Reliability over time
July 2023 – July 2026
Over the most recent 12 months (2025-08 to 2026-07), on-time arrivals averaged 77.9% against 76.5% in the 12 months before — broadly unchanged.
Data and methodology
Calculated by FlyerIntel from 1,400 SEA → PIT 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