Carrier route record
DLSLC→SJC
Delta Air Lines · Salt Lake City to San Jose
- Flights
- 892
- Period
- July 2025 to June 2026
- Share of route
- 49%
- Carriers
- 3
Historical statistics for July 2025 to June 2026, not live status. For today’s flights, check with Delta Air Lines.
Delta on SLC to SJC earns a B+. More than four flights in five arrive inside the 15-minute window the DOT uses to define an on-time arrival, which puts it 7 points better than the national rate of 77.6%. When something does go wrong the average delay runs a little over an hour. That rests on 892 flights, with a median arrival 9 minutes early.
Set against the rest of the country, Delta's SLC to SJC record is 7 points better than the US average of 77.6%. That gap is worth roughly 70 fewer late arrivals for every thousand flights.
Key figures
On time
84.6%
Arrivals under 15 minutes late, of 888 completed flights
Avg delay
73 min
Across delayed arrivals only, not all flights
Cancelled
0.45%
National rate is 1.81%
Whole route
87.0%
Every carrier on SLC to SJC, 1,810 flights
These figures cover 892 flights between July 2025 and June 2026. The median arrival is 9 minutes early, which is the part an average hides: most flights here are fine, and the on-time rate is decided by a tail of badly late ones. On-time means under 15 minutes late, the DOT's own threshold.
Carrier by carrier
Delta against every carrier on SLC to SJC
Delta flew 892 of the 1,810 flights on SLC to SJC, about 49% of it. Its 84.6% on time is 2 points worse than the route as a whole, which runs 87.0%. Ranked by on-time rate it is number two of three carriers on the route, where the range runs from SkyWest at 92.9% to Southwest at 77.9%. One of those carriers flew fewer than 365 flights here, so treat their positions as rough.
Only one carrier clears this site's 365-flight floor here, so there is no comparison to draw. The table below is the full picture.
| Airline | Flights | On time | Avg delay | Cancelled | Grade |
|---|---|---|---|---|---|
| SkyWest Airlines | 694 | 92.9% | 61 min | 0.14% | A+ |
| Delta Air Lines (this page) | 892 | 84.6% | 73 min | 0.45% | B+ |
| Southwest Airlinesthin sample | 224 | 77.9% | 48 min | 0.89% | B+ |
Flight by flight
Delta flight numbers on SLC to SJC
Departure window
When Delta runs best on this route
Departure time is the single lever a traveller controls, and it moves the odds more than most people expect. Each bar below is the on-time rate for flights scheduled to leave inside that window, across 892 flights.
- 5am–8am10 flights—
- 8am–11am24 flights—
- 11am–2pm365 flights85.5%
- 2pm–5pm128 flights89.1%
- 5pm–8pm4 flights—
- 8pm–5am361 flights81.0%
Scale runs 75% to 95%. Rows with fewer than 30 flights show a dash.
The best window here is not the first bank but the 2pm–5pm slot at 89.1% on time, ahead of 8pm–5am at 81.0%. Where the curve peaks mid-day rather than at dawn, the constraint is usually congestion at one end rather than the aircraft's own rotation. The 11am–2pm window is the busiest, with 365 flights scheduled in it.
Across the year
Delta on SLC to SJC through the year
August is the worst month at 74.2% on time, 18 points below April, the best at 92.5%. Summer afternoon convection and peak-season schedules land on the same weeks every year, so this is a pattern you can book around rather than a run of bad luck. January was the busiest month here, with 97 flights.
Across the week, Tuesday is the strongest day at 89.2% on time and Saturday the weakest at 81.2%. 8 points is a smaller lever than departure hour, but it is free.
Delay causes
Why Delta runs late on this route
One category carries most of the weight here. Carrier accounts for 64% of the 9,943 delay minutes carriers reported, and the remaining four split what is left. The split is by minutes rather than by flights, so a few very long delays count for as much as many short ones.
- 64%Carrier
- 29%Late-arriving aircraft
- 6%National Airspace System
- 1%Extreme weather
- 0%Security
The largest share of delay minutes, 64%, falls under carrier control: crew scheduling, maintenance, fuelling, baggage. Unlike weather, that is a management outcome, and it is the category where the gap between two carriers on the same schedule is genuinely earned. It accounts for 6,357 of the 9,943 delay minutes reported here. The split is drawn from 9,943 reported delay minutes.
Cancellations are rare at 0.45%, below the national 1.81% and low enough to earn the plus on the grade. Roughly one flight in 100 is called off; the risk here is arriving late, not not arriving.
Connections and stage length
What a delay here costs
5.3% of arrivals land an hour or more late, close to the national 8.1%. That is the figure that decides a connection, and it says a 60 to 75 minute layover is reasonable here while anything under 45 minutes is a bet. Most delays on this route last a little over an hour, which a normal layover absorbs.
The 584 miles between these two airports put this in the middle of the US network, around two and a half to three hours of block time. That is enough cruise to absorb a ten-minute late pushback and not enough to absorb thirty. It is also long enough that the aircraft usually flies three or four legs a day rather than six, which slows how fast delay compounds.
The return leg is a different operation and performs like one: it runs 92.3% on time across 892 flights, 8 points above this direction. Departure banks, aircraft rotations and the congestion at each end all differ, so scoring the two directions together would average away a real 8 points of difference.
One caution: this is a thin sample. 892 flights over twelve months is enough to clear this site's floor but not enough to pin the rate down tightly, and a single bad week moves it by more than a point. Treat the grade as a rough reading.
What to do with this
Booking Delta on SLC to SJC
Put together: treat all of this as provisional. 892 flights over twelve months is enough to clear this site's floor and not enough to be confident to better than a couple of points. The 84.6% headline is the most reliable number on the page; the hour and month splits below it are built on a few dozen flights each. 888 completed flights over 12 months sit behind that.
Related
Where to go next
- SLC to SJC, every carrier
- Delta on SJC to SLC, the return leg
- SkyWest Airlines on SLC to SJC92.9%
- Southwest Airlines on SLC to SJC77.9%
- Delta Air Lines network-wide record
- Salt Lake City International (SLC) delay statistics
- Norman Y. Mineta San Jose International (SJC) delay statistics
- The best time of day to fly, according to 7.04 million flight records
- Worst months to fly in the US, ranked by the data
Source: US DOT Bureau of Transportation Statistics, on-time performance data, July 2025 to June 2026. Last updated 15 September 2026; recomputed monthly. How this data is collected.