Carrier route record

WNBUR→SFO

Southwest Airlines · Burbank to San Francisco

Flights: 514
Period: September 2025 to August 2026
Share of route: 17%
Carriers: 3

Historical statistics for September 2025 to August 2026, not live status. For today’s flights, check with Southwest Airlines.

Southwest on BUR to SFO earns an F, which is as low as this site's scale goes for a reason. Only 40.4% of flights arrive inside the 15-minute window, 37 points worse than the national rate of 77.3%. Late arrivals average about an hour. Treat any tight connection here as a coin flip. That rests on 514 flights. The strongest carrier on the route with a full sample, SkyWest Airlines, flew 928 at 72.7% on time.

The national on-time rate over the same period is 77.3%, so Southwest on BUR to SFO runs 37 points behind the country as a whole. Across a thousand flights that is about 369 extra late arrivals.

On time

40.4%

Arrivals under 15 minutes late, of 505 completed flights

Avg delay

56 min

Across delayed arrivals only, not all flights

Cancelled

1.56%

National rate is 1.89%

Whole route

59.3%

Every carrier on BUR to SFO, 3,104 flights

These figures cover 514 flights between September 2025 and August 2026. Beyond the headline rate, 17.2% of arrivals land a full hour or more behind schedule, against 8.3% nationally.

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Carrier by carrier

Southwest against every carrier on BUR to SFO

Southwest flew 514 of the 3,104 flights on BUR to SFO, about 17% of it. Its 40.4% on time is 19 points worse than the route as a whole, which runs 59.3%. Ranked by on-time rate it is last of three carriers on the route, where the range runs from SkyWest at 72.7% to Southwest at 40.4%.

The choice of carrier is not cosmetic here. SkyWest Airlines arrives on time 72.7% of the time; United Airlines manages 57.8%. Sample sizes sit next to every figure, because a two-point gap across 1,662 flights means less than a ten-point one.

On-time performance by carrier on BUR to SFO
Airline	Flights	On time	Avg delay	Cancelled	Grade
SkyWest Airlines	928	72.7%	88 min	2.16%	C
United Airlines	1,662	57.8%	68 min	0.60%	D+
Southwest Airlines (this page)	514	40.4%	56 min	1.56%	F

The spread between SkyWest and United is 15 points, wide enough that it should decide the booking. On a hundred trips that is 15 more arrivals inside the on-time window.

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 37 points, against 15 points between the best and worst carrier.

5am–8am32 flights59.4%
8am–11am148 flights22.7%
11am–2pm145 flights48.3%
2pm–5pm80 flights42.5%
5pm–8pm62 flights53.2%
8pm–5am47 flights36.2%

Scale runs 15% to 65%.

Book the early departure. Flights leaving between 5am–8am arrive on time 59.4% of the time, against 22.7% for the morning window. That is 37 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 148 flights scheduled in it.

Across the year

Southwest on BUR to SFO through the year

Jan–Mar 202677 flights77.9%
Apr–Jun 2026260 flights28.2%
Jul–Sep 2026177 flights41.5%

Scale runs 20% to 85%.

Monthly volumes are too low here to break the year into twelve reliable readings. What the twelve-month total says is 40.4% on time across 514 flights.

Southwest on BUR to SFO did not run the same all year. Its best quarter was Jan–Mar 2026 at 77.9% on time and its weakest Apr–Jun 2026 at 28.2%, a swing of 50 points on roughly 171 flights a quarter. The twelve-month rate averages over that, so if you are flying in a weak quarter the quarter's own figure is the better guide.

Across the week, Saturday is the strongest day at 57.7% on time and Wednesday the weakest at 30.1%, a spread of 28 points.

Arrival by arrival

How late Southwest on BUR to SFO runs when it is late

The 301 late arrivals split 89 under half an hour, 125 between 30 and 60 minutes, and 87 an hour or more.

15+ min early60 flights11.9%
Within 15 min144 flights28.5%
15–29 min late89 flights17.6%
30–59 min late125 flights24.8%
1–2 hours late58 flights11.5%
2+ hours late29 flights5.7%

Scale runs 0% to 100%.

Share of 505 completed flights by arrival against schedule.

Time lost at the gate mostly stays lost. Of 237 departures that left 15 minutes late or more, only 9 made it up before arrival. In the other direction, 73 flights left on time yet arrived 15 minutes late or more, so that delay built up after pushback: in the air, in a holding pattern or on the ground at SFO.

The worst days

Worst days for Southwest on BUR to SFO

The latest arrival of the period was on 31 July 2026, 6 hours 1 minute behind schedule; most of its delay minutes were filed as extreme weather. On three of the five worst days the largest share was filed as a late-arriving aircraft.

The latest arrivals of Southwest on BUR to SFO in the period
Date	Arrived late by	Largest filed cause
31 July 2026	6 hours 1 minute	Extreme weather
20 April 2026	4 hours 37 minutes	Late-arriving aircraft
19 March 2026	4 hours 13 minutes	Late-arriving aircraft
6 March 2026	3 hours 47 minutes	Late-arriving aircraft
28 May 2026	3 hours 39 minutes	National Airspace System

Delay causes

Why Southwest runs late on this route

National Airspace System accounts for 65% of the 17,000 delay minutes carriers reported here, and the remaining four split what is left.

National Airspace System
65%
Late-arriving aircraft
21%
Carrier
11%
Extreme weather
2%

65% of delay minutes are charged to the National Airspace System: air traffic volume, runway configuration, ground stops. No carrier can price its way out of that, which is why airport choice moves the number here more than carrier choice does. That is 11,000 minutes out of 17,000, against a national NAS share of 21%. The split is drawn from 16,918 reported delay minutes.

Cancellations sit at 1.56% against a national 1.89%, which is ordinary. Diversions add another 0.19%.

Connections and stage length

What a delay here costs

17.2% of arrivals land a full hour or more behind schedule, against 8.3% nationally. Ninety minutes is the honest minimum for a connection here, and two hours if the onward flight is on a separate ticket.

At 326 miles this is a short hop, and stage length matters more than it looks. A flight this short spends under two hours in the air, which leaves almost nothing to claw back a late pushback with. Delay here is decided on the ground, in the turn, which is why the 5am–8am window matters as much as it does.

The return leg is a different operation and performs like one: it runs 49.7% on time across 514 flights, 9 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 9 points of difference.

One caution: this is a thin sample. 514 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 BUR to SFO

Put together: treat all of this as provisional. 514 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 40.4% headline is the most reliable number on the page; the hour and month splits below it are built on a few dozen flights each. 505 completed flights over 12 months sit behind that.

Where to go next

Source: US DOT Bureau of Transportation Statistics, on-time performance data, September 2025 to August 2026. Last updated 22 October 2026; recomputed monthly. How this data is collected.

Key figures