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Delta Air Lines / SLC → DEN

DL 1623 on time

Delta Air Lines 1623: Salt Lake City to Denver at 1:20 p.m.; Denver to Salt Lake City at 3:55 p.m. (past 12 months). Figures below the title are for SLC → DEN, its busiest leg

On time
84%
359 flights · likely 80–87%
Cancelled
0.6%
of scheduled flights
Typical arrival
−7 min
median vs schedule
When late
+66 min
average delay
Similar flights
84%
DL, same route & hour

About 1 in 6 DL 1623 flights from Salt Lake City arrived 15+ minutes late, diverted or cancelled over the past year (16%); 0.6% were cancelled. The typical flight landed 7 minutes early.

DL 1623: SLC → DEN

Scheduled to leave Salt Lake City at 1:20 p.m. local time. Over the past year it arrived on time 84% of the time (359 flights), in line with other DL flights on the route at that hour (84%). Last seen in the data Aug 31, 2026.

Month by month

40%70%100%Sep 2025: 90% on time (30 flights)90SepOct 2025: 83% on time (30 flights)83OctNov 2025: 86% on time (28 flights)86NovDec 2025: 87% on time (31 flights)87DecJan 2026: 93% on time (29 flights)93JanFeb 2026: 82% on time (28 flights)82FebMar 2026: 81% on time (31 flights)81MarApr 2026: 80% on time (30 flights)80AprMay 2026: 97% on time (31 flights)97MayJun 2026: 80% on time (30 flights)80JunJul 2026: 74% on time (31 flights)74JulAug 2026: 73% on time (30 flights)73Aug

By day of week

DayFlightsOn time
Monday5381%
Tuesday5285%
Wednesday5281%
Thursday5186%
Friday5186%
Saturday4984%
Sunday5184%

Why it was late

Airline (crew, maintenance, ops) 52%Air traffic & airport (NAS) 33%Late inbound plane 14%Severe weather 2%

All flights SLC → DEN · Connecting off DL 1623? Check the risk

DL 1623: DEN → SLC

Scheduled to leave Denver at 3:55 p.m. local time. Over the past year it arrived on time 81% of the time (271 flights), in line with other DL flights on the route at that hour (82%). Last seen in the data Aug 31, 2026.

Month by month

40%70%100%Aug 2025: 71% on time (31 flights)71AugSep 2025: 93% on time (27 flights)93SepOct 2025: 88% on time (26 flights)88OctNov 2025: 81% on time (27 flights)81NovDec 2025: 89% on time (19 flights)89DecFeb 2026: 82% on time (17 flights)82FebMar 2026: 87% on time (31 flights)87MarApr 2026: too few flights (12 flights)AprMay 2026: 100% on time (25 flights)100MayJun 2026: 89% on time (27 flights)89JunJul 2026: 60% on time (30 flights)60JulAug 2026: 50% on time (30 flights)50Aug

By day of week

DayFlightsOn time
Monday4180%
Tuesday4083%
Wednesday4083%
Thursday4178%
Friday4180%
Saturday2879%
Sunday4083%

Why it was late

Late inbound plane 62%Airline (crew, maintenance, ops) 19%Air traffic & airport (NAS) 15%Severe weather 4%

All flights DEN → SLC · Connecting off DL 1623? Check the risk

Questions

How often is DL 1623 from SLC to DEN late?

Delta Air Lines 1623 from Salt Lake City, UT to Denver, CO arrived 15 or more minutes late, was diverted or was cancelled on 16% of 359 scheduled flights between September 2025 and August 2026. 0.6% were cancelled.

How often is DL 1623 from DEN to SLC late?

Delta Air Lines 1623 from Denver, CO to Salt Lake City, UT arrived 15 or more minutes late, was diverted or was cancelled on 19% of 271 scheduled flights between September 2025 and August 2026. 0.7% were cancelled.

Flight numbers change. Figures cover flights with this airline, number and route only. "Likely range" is the 95% interval for the true on-time rate given the number of flights. This is history, not live status: check Delta Air Lines for today's flight. Method.