Carrier route record
WNSLC→OAK
Southwest Airlines · Salt Lake City to Oakland
- Flights
- 547
- Period
- September 2025 to August 2026
- Share of route
- 34%
- Carriers
- 2
Historical statistics for September 2025 to August 2026, not live status. For today’s flights, check with Southwest Airlines.
Southwest on SLC to OAK earns an A+. Close to nine flights in ten arrive inside the 15-minute window the DOT uses to define an on-time arrival, which puts it 10 points better than the national rate of 77.3%. When something does go wrong the average delay runs about an hour. That rests on 547 flights, with a median arrival 7 minutes early.
Set against the rest of the country, Southwest's SLC to OAK record is 10 points better than the US average of 77.3%. That gap is worth roughly 97 fewer late arrivals for every thousand flights.
Key figures
On time
87.0%
Arrivals under 15 minutes late, of 546 completed flights
Avg delay
57 min
Across delayed arrivals only, not all flights
Cancelled
0.18%
National rate is 1.89%
Whole route
90.2%
Every carrier on SLC to OAK, 1,621 flights
These figures cover 547 flights between September 2025 and August 2026. The median arrival is 7 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.
Fare search by Aviasales, a Travelpayouts partner. Booking through it may earn this site a commission at no cost to you; it changes no figure here.
Carrier by carrier
Southwest against every carrier on SLC to OAK
Southwest flew 547 of the 1,621 flights on SLC to OAK, about 34% of it. Its 87.0% on time is 3 points worse than the route as a whole, which runs 90.2%. Ranked by on-time rate it is last of two carriers on the route, where the range runs from SkyWest at 91.8% to Southwest at 87.0%.
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 | 1,074 | 91.8% | 54 min | 0.19% | A+ |
| Southwest Airlines (this page) | 547 | 87.0% | 57 min | 0.18% | A+ |
Timetable by Aviasales, a Travelpayouts partner. Booking through it may earn this site a commission at no cost to you; it changes no figure here.
Departure window
When Southwest runs best on this route
Departure time matters more here than the choice of carrier. The gap between the best and worst window is 24 points, against half a point between the best and worst carrier.
- 5am–8am109 flights98.1%
- 8am–11am137 flights89.8%
- 11am–2pm125 flights87.2%
- 2pm–5pm36 flights88.9%
- 5pm–8pm85 flights75.3%
- 8pm–5am55 flights74.5%
Scale runs 65% to 100%.
Book the early departure. Flights leaving between 5am–8am arrive on time 98.1% of the time, against 74.5% for the overnight window. That is 24 points of difference for no extra money, and it comes from the same aircraft having had no earlier flight to fall behind on. The 8am–11am window is the busiest, with 137 flights scheduled in it.
Across the year
Southwest on SLC to OAK through the year
September is the best month on the calendar at 96.4% on time. Shoulder season thins the schedule and takes the summer weather with it, and the operation gets its margin back. February was the busiest month here, with 70 flights.
Across the week, Tuesday is the strongest day at 94.4% on time and Sunday the weakest at 82.2%, a spread of 12 points.
Arrival by arrival
How late Southwest on SLC to OAK runs when it is late
Southwest on SLC to OAK often beats the schedule: 158 of 546 completed flights, 29%, arrived 15 minutes or more early. The 71 late arrivals split 31 under half an hour, 19 between 30 and 60 minutes, and 21 an hour or more.
- 15+ min early158 flights28.9%
- Within 15 min317 flights58.1%
- 15–29 min late31 flights5.7%
- 30–59 min late19 flights3.5%
- 1–2 hours late13 flights2.4%
- 2+ hours late8 flights1.5%
Scale runs 0% to 100%.
Share of 546 completed flights by arrival against schedule.
A late pushback is often recovered here: of 102 departures that left 15 minutes late or more, 43 still arrived on time. 12 flights left on time and still arrived late.
The worst days
Worst days for Southwest on SLC to OAK
The latest arrival of the period was on 30 August 2026, 5 hours 26 minutes behind schedule; most of its delay minutes were filed as carrier-caused (crew, maintenance, fuelling, baggage). The five worst days are spread across August, February, May and April, with no single month standing out.
| Date | Arrived late by | Largest filed cause |
|---|---|---|
| 30 August 2026 | 5 hours 26 minutes | Carrier |
| 18 February 2026 | 4 hours 16 minutes | Extreme weather |
| 29 May 2026 | 3 hours 8 minutes | Carrier |
| 27 April 2026 | 2 hours 55 minutes | Late-arriving aircraft |
| 18 February 2026 | 2 hours 22 minutes | Late-arriving aircraft |
Delay causes
Why Southwest runs late on this route
Late-arriving aircraft accounts for 53% of the 4,019 delay minutes carriers reported here, and the remaining four split what is left.
- 53%Late-arriving aircraft
- 34%Carrier
- 7%Extreme weather
- 6%National Airspace System
53% of delay minutes trace back to a late-arriving aircraft, meaning the plane was already behind before it got here. Across 4,019 reported delay minutes here, that single category outweighs weather by 7 to one. The split is drawn from 4,019 reported delay minutes.
The practical consequence: the 5am–8am departure is the one that starts clean. Its aircraft has no earlier leg to be late from, which is exactly why that window shows 98.1% on time here.
Cancellations are rare at 0.18%, below the national 1.89% 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
Badly late arrivals are rare here: only 3.8% land an hour or more behind schedule, against 8.3% nationally. Connections built on this flight are about as safe as US domestic connections get, though a cancelled flight still ignores every layover you give it.
The 588 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.
The return leg is a different operation and performs like one: it runs 75.5% on time across 547 flights, 12 points below 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 12 points of difference.
One caution: this is a thin sample. 547 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 Southwest on SLC to OAK
Put together: treat all of this as provisional. 547 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 87.0% headline is the most reliable number on the page; the hour and month splits below it are built on a few dozen flights each. 546 completed flights over 12 months sit behind that.
Related
Where to go next
- SLC to OAK, every carrier
- Southwest on OAK to SLC, the return leg
- SkyWest Airlines on SLC to OAK91.8%
- Southwest Airlines network-wide record
- Salt Lake City International (SLC) delay statistics
- Oakland International (OAK) delay statistics
- Why the first flight of the morning is statistically safest
- The best time of day to fly, according to 7.05 million flight records
Source: US DOT Bureau of Transportation Statistics, on-time performance data, September 2025 to August 2026. Last updated ; recomputed monthly. How this data is collected.