Flight Reliability
AS 551 · Alaska Airlines
Seattle → Las Vegas (SEA–LAS)96% of its flights flew this route. The rest (SLC–SEA) are included in these numbers.
83
Pretty Reliable
WanderNerd Reliability Score
- 80%
- Arrive within 15 minutes
- 3 min
- Average arrival delay
- 1.1%
- Cancelled
- 6 min early
- Median arrival delay
Based on 262 historical flights. Data through May 2026.
What the data says
Friday is doing you no favors.
AS 551 arrived on time 88% of the time on Wednesdays. On Fridays: 73%.
Slipping a little lately.
AS 551 arrived on time 81% of the time over the last three months in the data, compared with 84% in the three months before that.
The breakdown
- Mon73%(37 flights)
- Tue80%(39 flights)
- Wed88%(40 flights)
- Thu76%(38 flights)
- Fri73%(37 flights)
- Sat83%(29 flights)
- Sun85%(39 flights)
97%
May
Jun 46% → May 97% on time
| Month | On-time percentage | Flights |
|---|---|---|
| June 2025 | 46% | 11 |
| August 2025 | 67% | 12 |
| September 2025 | 79% | 29 |
| October 2025 | 80% | 30 |
| November 2025 | 79% | 29 |
| December 2025 | 75% | 16 |
| January 2026 | 84% | 25 |
| February 2026 | 92% | 25 |
| March 2026 | 60% | 25 |
| April 2026 | 85% | 27 |
| May 2026 | 97% | 30 |
- Departures on time
- 78%
- Diverted
- 0%
- Flights flown
- 259
- Months covered
- 11
Same route, other flights
Keep nerding
Based on 262 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.