PDX to SEA flight delays & on-time performance
Nonstop flights from Portland International Airport to Seattle–Tacoma International Airport · 129 miles · Aug 2025 – Jul 2026
No FAA-reported ground stops or delays at PDX or SEA right now. Individual flights can still be delayed by the airline; check with your airline for your flight.
Key facts
- Flights from Portland (PDX) to Seattle (SEA) arrived on time 85% of the time in Aug 2025 – Jul 2026, better than the 78% national average.
- 0.7% were cancelled, and 4% arrived an hour or more late.
- Delta Air Lines was the most punctual airline here (88% on time); Alaska Airlines was the least (83%).
- Departures scheduled around 5am did best (95% on time); around 9am did worst (78%).
- Saturday was the most reliable day to fly (88% on time) and Thursday the least (82%).
- The largest source of delay minutes was airline (crew, maintenance, cleaning, fueling) (45%).
Which airline is most on time from PDX to SEA?
Ranked by on-time arrival rate. Regional airlines fly under their partner's brand (e.g. SkyWest for Delta Connection or United Express).
| Airline | On time | Cancelled | Avg delay | 1 hr+ late | Flights |
|---|---|---|---|---|---|
| Delta Air Lines | 88% | 0.0% | 8 min | 2.1% | 281 |
| SkyWest AirlinesRegional airline operating flights for United Express, Delta Connection, American Eagle and Alaska. | 86% | 0.6% | 9 min | 4.0% | 3,504 |
| Alaska Airlines | 83% | 1.2% | 9 min | 2.6% | 1,157 |
Best time of day to fly
On-time arrival rate by scheduled departure hour (local time).
- 5am95%419 flights
- 6am92%297 flights
- 7am87%526 flights
- 8am85%87 flights
- 9am78%488 flights
- 10am84%362 flights
- 11am91%289 flights
- 12pm83%174 flights
- 1pm85%497 flights
- 2pm84%262 flights
- 3pm86%389 flights
- 5pm84%492 flights
- 7pm81%365 flights
- 8pm79%108 flights
- 9pm88%50 flights
- 10pm90%71 flights
Best day of the week
On-time arrival rate by day of departure.
- Monday86%0.4% cancelled
- Tuesday88%0.6% cancelled
- Wednesday85%0.4% cancelled
- Thursday82%0.6% cancelled
- Friday83%1.4% cancelled
- Saturday88%0.8% cancelled
- Sunday86%0.7% cancelled
On-time trend by month
Why flights are late
Share of delay minutes by cause, as reported by airlines to the DOT.
- Airline (crew, maintenance, cleaning, fueling)45%
- Air traffic control & airport congestion21%
- Late-arriving aircraft20%
- Extreme weather14%
- Security0%
Why flights are cancelled
Share of cancellations by reason.
- Air traffic control & airport congestion47%
- Airline (crew, maintenance, cleaning, fueling)26%
- Extreme weather26%
- Security0%
PDX to SEA: common questions
- How often are PDX to SEA flights on time?
- 85% of flights arrived less than 15 minutes late in Aug 2025 – Jul 2026, compared with 78% for all US flights.
- How often are flights from Portland to Seattle cancelled?
- 0.7% of scheduled flights were cancelled (34 of 4,942).
- How long are typical delays?
- Across all flights the average arrival delay was 9 min (early arrivals count as zero). Flights that were late arrived 54 min behind schedule on average, and 3.6% of flights were an hour or more late.
- How long is taxi time at PDX?
- Flights on this route spent 20 min taxiing from the gate to takeoff on average.
Related routes
Return trip: SEA to PDX — 83% on time
More flights from Portland
Data: U.S. DOT Bureau of Transportation Statistics, Aug 2025 – Jul 2026 (12 months). Latest month published by BTS: July 2026. Route: PDX → SEA, nonstop flights by US airlines that report to the DOT. How we calculate this.