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Flight Reliability

DL 823 · Delta Air Lines

Atlanta → San Francisco (ATL–SFO)

68
Usually Fine
WanderNerd Reliability Score
67%
Arrive within 15 minutes
15 min
Average arrival delay
0.8%
Cancelled
4 min
Median arrival delay

Based on 362 historical flights. Data through May 2026.

What the data says

The 3–6 PM departure wins.

DL 823 departing between 3–6 PM arrived on time 70% of the time, versus 48% between 12–3 PM.

Mondays have been rough.

DL 823 arrived on time 81% of the time on Tuesdays and just 56% on Mondays. That gap is worth planning around.

A bit behind the ATL–SFO route.

DL 823 arrived on time 67% of the time, versus 73% across the ATL–SFO route.

Lagging the Delta Air Lines network.

DL 823 arrived on time 67% of the time, versus 81% across the Delta Air Lines network.

The breakdown

On-time by weekday
  • Mon56%(52 flights)
  • Tue81%(52 flights)
  • Wed62%(52 flights)
  • Thu73%(51 flights)
  • Fri63%(51 flights)
  • Sat74%(49 flights)
  • Sun65%(51 flights)
On-time by departure window
  • 9 AM–12 PM56%(25 flights)
  • 12–3 PM48%(25 flights)
  • 3–6 PM70%(308 flights)
On-time trend by month
55%
May

Jun 63% → May 55% on time

On-time arrival percentage by month
MonthOn-time percentageFlights
June 202563%30
July 202561%31
August 202561%31
September 202570%30
October 202561%31
November 202583%29
December 202577%30
January 202668%28
February 202661%28
March 202687%30
April 202662%29
May 202655%31
Departures on time
78%
Diverted
0.3%
Flights flown
358
Months covered
12

Same route, other flights

Keep nerding

Based on 362 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.