Flight profile · Delta Air Lines

DL638

Boston (BOS) to Atlanta (ATL) · scheduled 4:55 PM – 7:50 PM

FlyerIntel does not track flights in the air. This page describes how DL638 has historically performed, which is a different and more useful question when you are deciding what to book. For today’s status, check with Delta Air Lines.

How DL638 performs

844 operations, 2023-09-05 to 2026-06-27.

On-time arrivals
76.0%
635 of 835 completed
Cancellation rate
0.71%
6 cancelled
Median arrival delay
-4 min
Average 7.4 min
Severe delays
7.1%
Arrived 60+ minutes late
Delay when late
62 min
Average, when 15+ min late
Departure punctuality
71.7%
Left the gate on time

DL638 arrived on time 76.0% of the time, against 78.8% for all BOSATL flights — this specific departure is 2.8 percentage points worse than the route as a whole. Against Delta Air Lines’s own flights on this route it is 6.3 points worse.

Source: US DOT Bureau of Transportation Statistics · 844 operations between 2023-09-05 to 2026-06-27

Against the rest of the route

On timeCancelledMedian delaySevereFlights
DL63876.0%0.71%-4 min7.1%844
Delta Air Lines on BOSATL82.3%1.06%-9 min6.4%10,882
All BOSATL flights78.8%1.32%-8 min7.8%15,002

Source: FlyerIntel analysis of US DOT BTS data · 2023-09-05 to 2026-06-27

By day of week

Does DL638 run worse on particular days?

Monday71.9%
Tuesday82.8%
Wednesday80.3%
Thursday70.2%
Friday77.5%
Saturday
Sunday75.0%

Tuesday is historically the most reliable day and Thursday the least, a gap of 12.5 percentage points.

Source: FlyerIntel analysis of US DOT BTS data · 2023-09-05 to 2026-06-27 · Days with fewer than 120 operations are not scored.

Other routes DL638 has flown

A flight number is a slot in a schedule, and carriers reassign it. These are the other city pairs this number served in the analysis period.

RouteOperatedFlightsOn time
EWRSLC Newark to Salt Lake City2026-05-092026-06-066
BUFDTW Buffalo to Detroit2026-01-052026-02-1138
SLCJFK Salt Lake City to New York2025-02-132025-03-0824
BNABOS Nashville to Boston2025-01-112025-02-085
BOSBNA Boston to Nashville2025-01-112025-02-085
SANATL San Diego to Atlanta2023-12-072024-01-0730
ATLDAL Atlanta to Dallas2023-07-102023-09-0448
ATLTVC Atlanta to Traverse City2023-07-012023-07-096
TVCATL Traverse City to Atlanta2023-07-012023-07-096
ATLMKE Atlanta to Milwaukee2023-07-032023-07-031

Because the same number has served different journeys, the statistics above describe only the route DL638 currently operates. Blending them would produce an average of two different flights.

Data and methodology

Calculated by FlyerIntel from 844 records of DL638 operating BOSATL, published by the US DOT Bureau of Transportation Statistics. A flight counts as delayed when it arrives 15 or more minutes after schedule. Cancelled and diverted flights are excluded from the on-time rate and reported separately. Flight numbers are resolved as carrier plus number plus route, because the same number serves different routes over time.

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