Flight Reliability
AS 538 · Alaska Airlines
Seattle → Chicago (SEA–ORD)
79
Usually Fine
WanderNerd Reliability Score
- 79%
- Arrive within 15 minutes
- 4 min
- Average arrival delay
- 0.9%
- Cancelled
- 6 min early
- Median arrival delay
Based on 350 historical flights. Data through May 2026.
What the data says
Thursdays have been rough.
AS 538 arrived on time 88% of the time on Saturdays and just 71% on Thursdays. That gap is worth planning around.
The breakdown
- Mon74%(50 flights)
- Tue81%(47 flights)
- Wed86%(49 flights)
- Thu71%(48 flights)
- Fri78%(49 flights)
- Sat88%(48 flights)
- Sun75%(52 flights)
- 12–3 AM—(8 flights)
- 3–6 PM78%(310 flights)
- 6–9 PM80%(25 flights)
97%
May
Jun 77% → May 97% on time
| Month | On-time percentage | Flights |
|---|---|---|
| June 2025 | 77% | 30 |
| July 2025 | 57% | 30 |
| August 2025 | 43% | 30 |
| September 2025 | 77% | 30 |
| October 2025 | 93% | 27 |
| November 2025 | 81% | 26 |
| December 2025 | 77% | 22 |
| January 2026 | 81% | 31 |
| February 2026 | 100% | 28 |
| March 2026 | 83% | 29 |
| April 2026 | 83% | 29 |
| May 2026 | 97% | 31 |
- Departures on time
- 74%
- Diverted
- 1.1%
- Flights flown
- 343
- Months covered
- 12
Same route, other flights
Keep nerding
Based on 350 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.