Flight Reliability
DL 473 · Delta Air Lines
Seattle → Boston (SEA–BOS)
81
Pretty Reliable
WanderNerd Reliability Score
- 80%
- Arrive within 15 minutes
- 1 min early
- Average arrival delay
- 1.7%
- Cancelled
- 7 min early
- Median arrival delay
Based on 363 historical flights. Data through May 2026.
What the data says
Saturdays have been rough.
DL 473 arrived on time 87% of the time on Wednesdays and just 69% on Saturdays. That gap is worth planning around.
A bit ahead of the SEA–BOS route.
DL 473 arrived on time 80% of the time, versus 75% across the SEA–BOS route.
Ticking up lately.
DL 473 arrived on time 85% of the time over the last three months in the data, compared with 78% in the three months before that.
The breakdown
- Mon84%(50 flights)
- Tue84%(51 flights)
- Wed87%(52 flights)
- Thu82%(51 flights)
- Fri77%(51 flights)
- Sat69%(52 flights)
- Sun76%(50 flights)
94%
May
Jun 79% → May 94% on time
| Month | On-time percentage | Flights |
|---|---|---|
| June 2025 | 79% | 29 |
| July 2025 | 76% | 29 |
| August 2025 | 68% | 31 |
| September 2025 | 70% | 30 |
| October 2025 | 90% | 31 |
| November 2025 | 86% | 28 |
| December 2025 | 81% | 31 |
| January 2026 | 76% | 29 |
| February 2026 | 78% | 27 |
| March 2026 | 84% | 31 |
| April 2026 | 77% | 30 |
| May 2026 | 94% | 31 |
- Departures on time
- 79%
- Diverted
- 0%
- Flights flown
- 357
- Months covered
- 12
Same route, other flights
Keep nerding
Based on 363 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.