Route profile
PHL→SLC
Flight reliability, delays and best times to fly from Philadelphia to Salt Lake City, 1,927 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 29% of comparable major US routes (4,598 compared)
Calculated from 2,262 flights. How this is calculated · What counts as on time
PHL → SLC arrives on time 77.3% of the time; the return trip, SLC → PHL, arrives on time 81.6% of the time, a 4.2-point gap between the two directions of the same city pair.
PHL → SLC spends 28.9 minutes on the ground on a 1,927-mile trip: 20.3 minutes from pushback to wheels-up at PHL and 8.6 minutes from touchdown to gate at SLC.
Source: US DOT Bureau of Transportation Statistics · Data covering July 2023 – July 2026
What stands out
Reliability here swings unusually widely by season, a wider month-to-month spread than 99% of 3,357 comparable routes.
90.7% on time in a typical October, against 60.3% in 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 PHL to SLC differs most from similar routes by hour, weekday, month and airline, July 2023 – July 2026.
PHL to SLC struggles most at 6 AM: 79.1% of its flights scheduled then arrive on time, 10.7 points behind the 89.8% on routes of similar length at the same hour. Against all other routes the gap is 11.7 points.
PHL to SLC is at its best against routes of similar length for flights scheduled at 6 PM: 74.9% arrive on time, 5 points ahead of the 69.9% those routes manage at that hour. Against all other routes the gap is 6.3 points.
Saturday is the day PHL to SLC slips furthest against routes of similar length, 72.9% on time where they average 79.0%, 6.1 points lower. Against all other routes the gap is 6.2 points.
May is kinder to PHL to SLC than to routes of similar length: 88.1% on time against 76.2%, 11.9 points better. Against all other routes the gap is 12.9 points.
In July, PHL to SLC runs 10.1 points below routes of similar length, 60.3% on time to 70.4%. Against all other routes the gap is 9.4 points.
PHL to SLC against comparable routes
July 2023 – July 2026| Measure | This route | Compared with | Them | Gap | Flights behind it |
|---|---|---|---|---|---|
| Hour: 6 AM departures | 79.1% | routes of similar length | 89.8% | −10.7 pts | 172 here, 69,544 there |
| Hour: 6 PM departures | 74.9% | routes of similar length | 69.9% | +5.0 pts | 665 here, 54,783 there |
| Weekday: Saturday | 72.9% | routes of similar length | 79.0% | −6.1 pts | 273 here, 148,936 there |
| Month: May | 88.1% | routes of similar length | 76.2% | +11.9 pts | 176 here, 93,695 there |
| Month: July | 60.3% | routes of similar length | 70.4% | −10.1 pts | 290 here, 130,670 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 1,927 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
44 min late
against a median of 5 min early
Percentiles over 2,262 operations; cancelled and diverted flights are counted separately.
Will your connection be tight enough?
Layovers at SLC after arriving from PHL.
| Connection time | Chance of missing | Reads as |
|---|---|---|
| 30 min | 39% | Likely to miss |
| 45 min | 22% | High risk |
| 60 min | 13% | Some risk |
| 90 min | 7.8% | Some risk |
| 120 min | 5.1% | Some 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 1.95% of the time and diverts 0.18% of the time, which a late arrival never shows up in.
Chance of missing is the share of 2,214 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 44 minutes late (90th-percentile gate arrival delay), over 2,262 operations.
Any other layover length: connection checker.
Why PHL → SLC 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
airspace and airport capacity, including weather-driven flow control
weather severe enough to stop this flight specifically
Share of the delay minutes US DOT attributed to each cause for PHL → SLC. Only delays of 15 minutes or more are attributed. What the five causes mean
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 | 1,845 | 80.8% | 1.14% | -6 min | 6.2% |
| American Airlines | 417 | 61.3% | 5.52% | 3 min | 16.0% |
Delta Air Lines flew 81.6% of the 2,262 flights listed. American Airlines cancelled 5.52% of its flights here against 1.14% for Delta Air Lines.
Delta Air Lines arrived on time 19.5 percentage points more often than American 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 |
|---|---|---|---|
| DL2023 Delta Air Lines | 7:05 AM | 783 | 83.7% |
Weekly and seasonal patterns
By day of week
Sunday is historically the most reliable day and Saturday the least, a gap of 6.1 percentage points.
By month
- Jan: 78.3%
- Feb: 80.0%
- Mar: 82.1%
- Apr: 86.1%
- May: 88.1%
- Jun: 72.1%
- Jul: 60.3%
- Aug: 69.6%
- Sep: 84.4%
- Oct: 90.7%
- Nov: 81.9%
- Dec: 73.1%
July is historically the weakest month and October the strongest, a spread of 30.4 percentage points.
Reliability over time
July 2023 – July 2026
Over the most recent 12 months (2025-08 to 2026-07), on-time arrivals averaged 78.1% against 74.8% in the 12 months before — improving by 3.3 percentage points.
Data and methodology
Calculated by FlyerIntel from 2,262 PHL → 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