Route Reliability
Seattle → Portland
SEA–PDX · 129 miles · Seattle–Tacoma International Airport to Portland International Airport
- 83%
- Arrive within 15 minutes
- 3 min
- Average arrival delay
- 0.6%
- Cancelled
- 6,678
- Flights in the data
Data through May 2026.
Who flies it best
Ranked by on-time arrivals. Historical results, not predictions.
- 1.Delta Air Lines88%2,649 flights
- 2.Alaska Airlines80%4,029 flights
What the data says
Morning flights do better here.
SEA–PDX flights departing between 3–6 AM arrived on time 94% of the time, versus 78% between 9 PM–12 AM.
Wednesday comes out ahead.
A small edge: 85% on time on Wednesdays against 79% on Thursdays.
Delta Air Lines runs this route best.
Delta Air Lines arrived on time 88% of the time on this route; Alaska Airlines managed 80%.
Ticking up lately.
SEA–PDX flights arrived on time 86% of the time over the last three months in the data, compared with 83% in the three months before that.
Best historical flights
Ranked by on-time arrivals, minimum 100 flights. Past performance, not a promise.
Top flights by on-time rate
More flights on this route
The breakdown
- Mon83%(973 flights)
- Tue84%(971 flights)
- Wed85%(953 flights)
- Thu79%(958 flights)
- Fri83%(945 flights)
- Sat84%(868 flights)
- Sun83%(969 flights)
- 3–6 AM94%(186 flights)
- 6–9 AM92%(950 flights)
- 9 AM–12 PM84%(1257 flights)
- 12–3 PM84%(815 flights)
- 3–6 PM81%(1130 flights)
- 6–9 PM79%(1141 flights)
- 9 PM–12 AM78%(1158 flights)
Jun 75% → May 86% on time
| Month | On-time percentage | Flights |
|---|---|---|
| June 2025 | 75% | 627 |
| July 2025 | 78% | 662 |
| August 2025 | 81% | 640 |
| September 2025 | 86% | 578 |
| October 2025 | 85% | 572 |
| November 2025 | 87% | 503 |
| December 2025 | 74% | 501 |
| January 2026 | 86% | 486 |
| February 2026 | 89% | 438 |
| March 2026 | 81% | 523 |
| April 2026 | 92% | 546 |
| May 2026 | 86% | 561 |
Keep nerding
Based on 6,678 historical flights, because apparently we checked. Historical flight data: U.S. Bureau of Transportation Statistics, June 2025 – May 2026. Data through May 2026. How we calculate this.