Route profile
SLC→ONT
Flight reliability, delays and best times to fly from Salt Lake City to Ontario, 558 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 95% of comparable major US routes (4,598 compared)
Calculated from 3,727 flights. How this is calculated
SLC → ONT arrives on time 88.9% of the time; the return trip, ONT → SLC, arrives on time 91.8% of the time, a 3.0-point gap between the two directions of the same city pair.
SLC → ONT spends 22.6 minutes on the ground on a 558-mile trip: 17.6 minutes from pushback to wheels-up at SLC and 5.0 minutes from touchdown to gate at ONT.
Source: US DOT Bureau of Transportation Statistics · Data covering July 2023 – July 2026
What stands out
This route holds up about the same all year, a steadier seasonal pattern than 100% of 3,357 comparable routes.
92.1% on time in its best month (October) against 86.5% in its worst (July).
Source: FlyerIntel analysis of US DOT BTS data · July 2023 – July 2026 · Ranked against every other route with the same kind of figure and at least 3,357 in the comparison.
What sets this route apart
Where SLC to ONT differs most from similar routes by hour, weekday, month and airline, July 2023 – July 2026.
SLC to ONT is at its best against routes of similar length for flights scheduled at 9 PM: 86.2% arrive on time, 18 points ahead of the 68.2% those routes manage at that hour. Against all other routes the gap is 16.7 points.
SLC to ONT holds up on Fridays better than routes of similar length do: 89.9% on time to their 76.8%, a 13.1 points lead. Against all other routes the gap is 13.7 points.
July is kinder to SLC to ONT than to routes of similar length: 86.5% on time against 70.1%, 16.4 points better. Against all other routes the gap is 16.8 points.
SkyWest Airlines does better on SLC to ONT than on its routes of similar length: 92.9% on time here, 85.4% there, 7.5 points apart. Against all other routes the gap is 11.7 points.
SLC to ONT against comparable routes
July 2023 – July 2026| Measure | This route | Compared with | Them | Gap | Flights behind it |
|---|---|---|---|---|---|
| Hour: 9 PM departures | 86.2% | routes of similar length | 68.2% | +18.0 pts | 217 here, 65,937 there |
| Weekday: Friday | 89.9% | routes of similar length | 76.8% | +13.1 pts | 543 here, 273,728 there |
| Month: July | 86.5% | routes of similar length | 70.1% | +16.4 pts | 438 here, 202,578 there |
| Airline: SkyWest Airlines | 92.9% | routes of similar length | 85.4% | +7.5 pts | 1,120 here, 107,781 there |
Each comparison pools the flights of other routes, with this route’s own left out. Similar length means within 15% of this route’s 558 miles, with at least 5 such routes. A bucket is set against the most comparable group that has enough flights: similar length, then the same origin (at least 3 routes), then all other routes. Hours, weekdays and months appear only where both sides have 120 completed flights, and airlines where both have 600. The gap must be at least 2 points and 2 standard errors, and only the largest gap each way is kept per measure. These are differences in the flights counted, not causes.
When it goes wrong
July 2023 – July 2026
17 min late
against a median of 9 min early
Percentiles over 3,727 operations; cancelled and diverted flights are counted separately.
Will your connection be tight enough?
Layovers at ONT after arriving from SLC.
| Connection time | Chance of missing | Reads as |
|---|---|---|
| 30 min | 25% | High risk |
| 45 min | 11% | Some risk |
| 60 min | 6.4% | Some risk |
| 90 min | 3.4% | Low risk |
| 120 min | 2.0% | 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 0.99% of the time and diverts 0.05% of the time, which a late arrival never shows up in.
Chance of missing is the share of 3,688 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 17 minutes late (90th-percentile gate arrival delay), over 3,727 operations.
Any other layover length: connection checker.
Best time to fly
SLC → ONT flights departing 5–9 AM arrived on time 94.9% of the time, against 85.5% for 9 PM–5 AM departures, a gap of 9.4 percentage points.
By departure window
By departure hour
- 12 AM to 7 AM: too few flights to score
- 8 AM: 94.9% on time from 218 flights
- 9 AM to 10 AM: too few flights to score
- 11 AM: 89.1% on time from 1,156 flights
- 12 PM to 2 PM: too few flights to score
- 3 PM: 91.9% on time from 1,064 flights
- 4 PM to 8 PM: too few flights to score
- 9 PM: 86.2% on time from 217 flights
- 10 PM: 86.3% on time from 490 flights
- 11 PM: 84.0% on time from 381 flights
Departure windows with fewer than 120 flights are not scored.
Why SLC → ONT runs late
July 2023 – July 2026
crew, maintenance, boarding and fueling, all within the carrier’s control
the inbound aircraft was late, so this flight started late
weather severe enough to stop this flight specifically
airspace and airport capacity, including weather-driven flow control
Share of the delay minutes US DOT attributed to each cause for SLC → ONT. Only delays of 15 minutes or more are attributed.
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 | 2,420 | 87.5% | 1.20% | -9 min | 3.9% |
| SkyWest Airlines | 1,121 | 92.9% | 0.09% | -8 min | 1.9% |
Delta Air Lines flew 68.3% of the 3,541 flights listed. Delta Air Lines cancelled 1.20% of its flights here against 0.09% for SkyWest Airlines.
SkyWest Airlines arrived on time 5.4 percentage points more often than Delta Air Lines on this route.
Other ways to fly Salt Lake City to Los Angeles
Airport pairs in the same two city markets, as the DOT defines them.
| Route | Flights | On time | Cancelled | Median delay | Score |
|---|---|---|---|---|---|
| SLC→LAX Salt Lake City to Los Angeles | 13,286 | 85.0% | 0.33% | -8 min | 84 |
| SLC→ONT this route Salt Lake City to Ontario | 3,727 | 88.9% | 0.99% | -9 min | 86 |
Weekly and seasonal patterns
By day of week
Tuesday is historically the most reliable day and Monday the least, a gap of 4.9 percentage points.
By month
- Jan: 86.8%
- Feb: 86.7%
- Mar: 86.6%
- Apr: 87.1%
- May: 91.3%
- Jun: 88.3%
- Jul: 86.5%
- Aug: 89.9%
- Sep: 88.6%
- Oct: 92.1%
- Nov: 91.6%
- Dec: 91.4%
July is historically the weakest month and October the strongest, a spread of 5.6 percentage points.
Reliability over time
July 2023 – July 2026
- July 2023: too few flights to score (101)
- August 2023: too few flights to score (93)
- September 2023: too few flights to score (90)
- October 2023: too few flights to score (93)
- November 2023: too few flights to score (89)
- December 2023: too few flights to score (107)
- January 2024: too few flights to score (95)
- February 2024: too few flights to score (78)
- March 2024: too few flights to score (88)
- April 2024: too few flights to score (107)
- May 2024: too few flights to score (118)
- June 2024: too few flights to score (119)
- July 2024: 81.7% from 123 flights
- August 2024: too few flights to score (110)
- September 2024: too few flights to score (99)
- October 2024: too few flights to score (94)
- November 2024: too few flights to score (88)
- December 2024: too few flights to score (94)
- January 2025: too few flights to score (97)
- February 2025: too few flights to score (81)
- March 2025: too few flights to score (91)
- April 2025: too few flights to score (90)
- May 2025: too few flights to score (113)
- June 2025: too few flights to score (114)
- July 2025: too few flights to score (116)
- August 2025: too few flights to score (118)
- September 2025: too few flights to score (110)
- October 2025: too few flights to score (115)
- November 2025: too few flights to score (88)
- December 2025: too few flights to score (90)
- January 2026: too few flights to score (92)
- February 2026: too few flights to score (89)
- March 2026: too few flights to score (94)
- April 2026: too few flights to score (99)
- May 2026: too few flights to score (115)
- June 2026: too few flights to score (113)
- July 2026: too few flights to score (116)
Over the most recent 12 months (2025-08 to 2026-07), on-time arrivals averaged 89.2% against 89.7% in the 12 months before — broadly unchanged.
Data and methodology
Calculated by FlyerIntel from 3,727 SLC → ONT 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