Route profile
SFO→SLC
Flight reliability, delays and best times to fly from San Francisco to Salt Lake City, 599 miles.
Right now
Aviation weather is not currently a factor.
Aviation weather is not currently a factor.
Route reliability
July 2023 – July 2026
Better than 56% of comparable major US routes (4,598 compared)
Calculated from 10,847 flights. How this is calculated
SFO → SLC arrives on time 79.0% of the time; the return trip, SLC → SFO, arrives on time 71.5% of the time, a 7.5-point gap between the two directions of the same city pair.
SFO → SLC spends 25.9 minutes on the ground on a 599-mile trip: 19.6 minutes from pushback to wheels-up at SFO and 6.3 minutes from touchdown to gate at SLC.
Source: US DOT Bureau of Transportation Statistics · Data covering July 2023 – July 2026
Why SFO → SLC flights are cancelled
July 2023 – July 2026
SFO → SLC cancelled 74 of 10,847 scheduled flights — about 1 in every 147. The reason filed most often was the airline, 62.2% of the cancellations coded on this route — about 1 in every 236 scheduled flights.
Share of cancellations
Of 74 cancelled departures carrying a reason code.
What each reason means
Crew, maintenance, aircraft cleaning, baggage or fueling: what BTS counts as within the carrier’s own control.
46 cancellations, 62.2% of the total.
Airport capacity, air traffic control flow programs, heavy traffic and ordinary bad weather. A system decision, not the airline’s.
18 cancellations, 24.3% of the total.
Conditions the carrier judged severe enough to stop the flight: a blizzard, a hurricane, a line of thunderstorms.
10 cancellations, 13.5% of the total.
A terminal evacuation, a security breach, screening equipment failure, or screening queues over 29 minutes.
0 cancellations, 0.0% of the total.
Reason codes are the operating airline’s own filing with US DOT, not an independent finding of fault. Ordinary bad weather is filed under air traffic, so weather’s full share is larger than its bar.
74 coded cancellations were recorded on SFO → SLC; the section appears from 50.
When it goes wrong
July 2023 – July 2026
45 min late
against a median of 7 min early
Percentiles over 10,847 operations; cancelled and diverted flights are counted separately.
Will your connection be tight enough?
Layovers at SLC after arriving from SFO.
| Connection time | Chance of missing | Reads as |
|---|---|---|
| 30 min | 35% | Likely to miss |
| 45 min | 20% | High risk |
| 60 min | 14% | Some risk |
| 90 min | 7.4% | Some risk |
| 120 min | 4.4% | Low risk |
This is one leg of a connection. Gate changes and the next flight's own schedule matter too. And a connection can fail before delay is even the question — this route cancels 0.68% of the time and diverts 0.04% of the time, which a late arrival never shows up in.
Chance of missing is the share of 10,769 arrivals on this route that landed later than the connection time less 30 minutes to reach the next gate.
The worst tenth of arrivals on this route land at least 45 minutes late (90th-percentile gate arrival delay), over 10,847 operations.
Any other layover length: connection checker.
Best time to fly
SFO → SLC flights departing 5–9 AM arrived on time 93.1% of the time, against 71.5% for 12–3 PM departures, a gap of 21.6 percentage points.
By departure window
By departure hour
- 12 AM to 4 AM: too few flights to score
- 5 AM: 96.6% on time from 640 flights
- 6 AM: 95.0% on time from 487 flights
- 7 AM: too few flights to score
- 8 AM: 88.1% on time from 624 flights
- 9 AM: 83.2% on time from 1,087 flights
- 10 AM: 78.4% on time from 844 flights
- 11 AM: too few flights to score
- 12 PM: 74.3% on time from 575 flights
- 1 PM: 70.2% on time from 1,655 flights
- 2 PM: 73.9% on time from 293 flights
- 3 PM: too few flights to score
- 4 PM: 70.4% on time from 1,058 flights
- 5 PM: 76.3% on time from 1,304 flights
- 6 PM: 81.8% on time from 711 flights
- 7 PM: 80.3% on time from 1,217 flights
- 8 PM: 70.2% on time from 172 flights
- 9 PM to 11 PM: too few flights to score
Departure windows with fewer than 120 flights are not scored.
Why SFO → SLC runs late
July 2023 – July 2026
the inbound aircraft was late, so this flight started late
crew, maintenance, boarding and fueling, all within the carrier’s control
airspace and airport capacity, including weather-driven flow control
weather severe enough to stop this flight specifically
screening or terminal security incidents
Share of the delay minutes US DOT attributed to each cause for SFO → SLC. Only delays of 15 minutes or more are attributed.
Late-arriving aircraft is the largest cause on SFO → SLC, at 52.8%: flights here mostly leave late because the plane came in late, and the day shows it: 5–9 AM departures arrived on time 93.1% of the time and 12–3 PM departures 71.5%.
How this route holds up in bad weather
July 2023 – July 2026
The harder-hit end is the one the flight leaves from, where a cancellation keeps it from departing at all. Bad weather cancels 1.7 times the normal rate at SFO against barely any change at SLC. Cancelled in bad weather against normal hours: SFO 1.5% against 0.9%, SLC 0.6% against 0.6%. Flights that did leave SLC in bad weather arrived on time 71.0% of the time, against 84.8% in normal hours.
Bad weather and normal hours at the airports
Scheduled departures, July 2023 – July 2026| Departures from | SFO | SLC |
|---|---|---|
| Cancelled in bad weather | 1.5% | 0.6% |
| Cancelled in normal hours | 0.9% | 0.6% |
| Arrived on time, bad weather | 73.0% | 71.0% |
| Arrived on time, normal hours | 79.8% | 84.8% |
| Departures in bad weather | 36,006 | 20,014 |
Of the carriers on this route, United Airlines (1.0% cancelled against 1.9% for the other carriers at SFO) cancelled the fewest departures from SFO in bad weather and SkyWest Airlines (3.0% cancelled against 1.2% for the other carriers at SFO) the most.
This route’s airlines in bad weather at SFO
All departures from SFO| Airline | Bad-weather departures | Cancelled | Other carriers |
|---|---|---|---|
| United Airlines | 13,903 | 1.0%below the others | 1.9% |
| Delta Air Lines | 3,513 | 0.8%below the others | 1.5% |
| Frontier Airlines | 1,057 | 1.8%about level | 1.5% |
| SkyWest Airlines | 7,724 | 3.0%above the others | 1.2% |
These are airport figures, not route figures: every scheduled departure from SFO and SLC, to any destination, in hours the weather report called bad. The airline rows count each carrier’s departures from SFO on every route.
Weather source and limits. In full: SFO (airlines), SLC, What Weather Costs Each Airport, Who Cancels More When the Weather Turns, Airports That Change Places When Weather Turns.
Airlines on this route
Carriers with at least 200 flights, by the airline that operated each one.
| Carrier | Flights | On time | Cancelled | Median delay | Severe |
|---|---|---|---|---|---|
| Delta Air Lines | 5,199 | 79.7% | 0.56% | -8 min | 7.3% |
| SkyWest Airlines | 3,737 | 80.5% | 0.59% | -8 min | 6.7% |
| United Airlines | 1,382 | 76.8% | 0.58% | -5 min | 8.7% |
| Frontier Airlines | 529 | 66.3% | 2.84% | 2 min | 13.2% |
Delta Air Lines flew 47.9% of the 10,847 flights listed. Frontier Airlines cancelled 2.84% of its flights here against 0.56% for Delta Air Lines.
SkyWest Airlines arrived on time 14.2 percentage points more often than Frontier Airlines on this route.
Flights on this route
Flight numbers with at least 600 operations here and still on the schedule.
| Flight | Scheduled | Operations | On time |
|---|---|---|---|
| DL1331 Delta Air Lines | 6:00 AM | 785 | 95.4% |
Weekly and seasonal patterns
By day of week
Tuesday is historically the most reliable day and Monday the least, a gap of 8.9 percentage points.
By month
- Jan: 81.3%
- Feb: 78.3%
- Mar: 76.1%
- Apr: 75.9%
- May: 73.0%
- Jun: 71.8%
- Jul: 78.6%
- Aug: 82.4%
- Sep: 86.0%
- Oct: 87.0%
- Nov: 82.9%
- Dec: 75.4%
June is historically the weakest month and October the strongest, a spread of 15.2 percentage points.
Reliability over time
July 2023 – July 2026
- July 2023: 89.2% from 292 flights
- August 2023: 82.0% from 284 flights
- September 2023: 84.8% from 287 flights
- October 2023: 91.0% from 333 flights
- November 2023: 89.1% from 313 flights
- December 2023: 80.0% from 321 flights
- January 2024: 76.7% from 288 flights
- February 2024: 77.5% from 266 flights
- March 2024: 61.0% from 272 flights
- April 2024: 66.4% from 287 flights
- May 2024: 70.7% from 290 flights
- June 2024: 77.7% from 264 flights
- July 2024: 80.8% from 289 flights
- August 2024: 81.5% from 289 flights
- September 2024: 85.8% from 275 flights
- October 2024: 87.8% from 287 flights
- November 2024: 77.4% from 276 flights
- December 2024: 74.4% from 305 flights
- January 2025: 84.5% from 298 flights
- February 2025: 79.4% from 283 flights
- March 2025: 76.9% from 321 flights
- April 2025: 88.4% from 328 flights
- May 2025: 81.9% from 327 flights
- June 2025: 76.3% from 305 flights
- July 2025: 75.5% from 314 flights
- August 2025: 83.6% from 294 flights
- September 2025: 87.6% from 250 flights
- October 2025: 81.7% from 284 flights
- November 2025: 81.1% from 265 flights
- December 2025: 71.5% from 294 flights
- January 2026: 82.5% from 270 flights
- February 2026: 77.8% from 285 flights
- March 2026: 88.2% from 324 flights
- April 2026: 71.0% from 294 flights
- May 2026: 65.7% from 306 flights
- June 2026: 61.8% from 291 flights
- July 2026: 69.3% from 296 flights
Over the most recent 12 months (2025-08 to 2026-07), on-time arrivals averaged 76.7% against 80.8% in the 12 months before — declining by 4.1 percentage points.
Data and methodology
Calculated by FlyerIntel from 10,847 SFO → SLC flight records from the US DOT Bureau of Transportation Statistics, covering July 2023 – July 2026. Late means 15 or more minutes past scheduled arrival; cancelled and diverted flights are left out of on-time rates.
Full methodology · Data sources · Report a problem
Related research: How Long a Layover Needs to Be · Two Airlines on One Route · Best Time of Day to Fly From Major US Airports
Analysis last recomputed