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Flight Reliability

DL 1331 · Delta Air Lines

San Francisco → Salt Lake City (SFO–SLC)

100
Nerd Approved
WanderNerd Reliability Score
97%
Arrive within 15 minutes
10 min early
Average arrival delay
0.5%
Cancelled
15 min early
Median arrival delay

Based on 365 historical flights. Data through May 2026.

What the data says

Skip Saturday if you can.

DL 1331 arrived on time 100% of the time on Fridays. On Saturdays: 92%.

Well ahead of the SFO–SLC route.

DL 1331 arrived on time 97% of the time, versus 79% across the SFO–SLC route.

Well ahead of the Delta Air Lines network.

DL 1331 arrived on time 97% of the time, versus 81% across the Delta Air Lines network.

Ticking up lately.

DL 1331 arrived on time 99% of the time over the last three months in the data, compared with 93% in the three months before that.

The breakdown

On-time by weekday
  • Mon98%(52 flights)
  • Tue92%(52 flights)
  • Wed96%(52 flights)
  • Thu98%(52 flights)
  • Fri100%(51 flights)
  • Sat92%(51 flights)
  • Sun100%(53 flights)
On-time by departure window
  • 3–6 AM97%(257 flights)
  • 6–9 AM95%(106 flights)
On-time trend by month
100%
May

Jun 93% → May 100% on time

On-time arrival percentage by month
MonthOn-time percentageFlights
June 202593%30
July 2025100%31
August 202594%31
September 202597%30
October 2025100%31
November 2025100%30
December 202590%31
January 2026100%30
February 202689%28
March 2026100%30
April 202697%30
May 2026100%31
Departures on time
96%
Diverted
0%
Flights flown
363
Months covered
12

Same route, other flights

Keep nerding

Based on 365 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.