Carrier performance at one airport

WN→OAK

Southwest Airlines at Oakland International

Departures: 28,173
Period: July 2025 to June 2026
Routes: 25
Rank here: #4 of 4

Southwest Airlines at Oakland lands a B+, about a point better than the national rate of 77.6%. About one flight in five arrive 15 minutes late or worse, and those flights are late by about 50 minutes on average. That is a workable record, not a spotless one. That rests on 28,173 flights, of which SkyWest Airlines flew 1,462 at 89.3% on time.

Measured against the airport rather than the country, Southwest Airlines runs about a point behind the 79.4% weighted average across all carriers at OAK. That is the comparison worth making: every operator here works the same runways, the same airspace and the same weather.

On time

78.5%

27,960 completed departures

Avg delay

50 min

Across delayed flights only

Cancelled

0.59%

At OAK, this carrier only

Rank here

Of 4 carriers clearing the floor at OAK

These figures cover 28,000 flights between July 2025 and June 2026. The median arrival is 4 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.

Against the competition

Every carrier at OAK, ranked

The choice of carrier is not cosmetic here. SkyWest Airlines arrives on time 89.3% of the time; Southwest Airlines manages 78.5%. Sample sizes sit next to every figure, because a two-point gap across 28,173 flights means less than a ten-point one.

On-time performance of all carriers departing OAK
Airline	Flights	On time	Avg delay	Cancelled	Grade
SkyWest Airlines	1,462	89.3%	62 min	0.48%	A+
Hawaiian Airlines	498	88.2%	171 min	2.41%	A
Alaska Airlines	1,222	85.7%	50 min	1.39%	A
Southwest Airlines (this page)	28,173	78.5%	50 min	0.59%	B+

SkyWest leads Southwest by 11 points. Real, but small enough that a better departure time on the weaker carrier can outweigh it.

Route by route

Where Southwest Airlines flies from OAK

Southwest Airlines operates 25 routes out of OAK with enough volume to report. Route records inside one carrier at one airport still spread widely, because a short shuttle and a transcontinental have very different exposure to a late inbound.

Southwest Airlines routes from OAK
Route	Flights	On time	Avg delay	Cancelled	Grade
OAK to LAS · Las Vegas	3,178	77.6%	53 min	0.66%	B+
OAK to SAN · San Diego	2,939	66.6%	49 min	0.95%	C+
OAK to BUR · Burbank	2,771	81.9%	53 min	1.15%	B
OAK to SNA · Santa Ana	2,319	85.6%	45 min	0.73%	A+
OAK to LAX · Los Angeles	2,100	79.7%	54 min	1.00%	B
OAK to PHX · Phoenix	1,931	77.4%	54 min	0.26%	B+
OAK to LGB · Long Beach	1,623	86.3%	49 min	0.25%	A+
OAK to DEN · Denver	1,607	73.0%	47 min	0.44%	C+
OAK to ONT · Ontario	1,489	82.5%	49 min	0.40%	B+
OAK to PDX · Portland	1,181	78.9%	54 min	0.42%	B+
OAK to SEA · Seattle	1,130	74.9%	47 min	0.27%	C+
OAK to SLC · Salt Lake City	596	79.5%	61 min	0.00%	B+
OAK to BOI · Boise	578	83.2%	53 min	0.00%	B+
OAK to MDW · Chicago	482	85.5%	33 min	0.21%	A+
OAK to PSP · Palm Springs	477	77.3%	45 min	0.84%	B+
OAK to DAL · Dallas	444	76.7%	52 min	0.90%	B+
OAK to GEG · Spokane	407	73.7%	46 min	0.00%	C+
OAK to HOU · Houston	376	80.0%	37 min	0.53%	B+
OAK to OGG · Kahului	365	77.2%	56 min	0.00%	B+
OAK to HNL · Honolulu	365	78.1%	44 min	0.00%	B+
OAK to LIH · Lihuethin sample	364	75.2%	53 min	0.00%	B+
OAK to AUS · Austinthin sample	359	75.7%	39 min	0.00%	B+
OAK to ABQ · Albuquerquethin sample	353	76.5%	47 min	0.00%	B+
OAK to SBA · Santa Barbarathin sample	296	86.0%	51 min	1.01%	A
OAK to EUG · Eugenethin sample	248	80.1%	40 min	0.81%	B+

Departure window

Best time of day for this operation

Departure time matters more here than the choice of carrier. The gap between the best and worst window is 29 points, against 11 points between the best and worst carrier. Each bar is the on-time rate for flights scheduled inside that window.

5am–8am4,968 flights94.0%
8am–11am5,039 flights87.1%
11am–2pm5,648 flights77.8%
2pm–5pm4,563 flights71.4%
5pm–8pm4,840 flights70.2%
8pm–5am3,115 flights64.8%

Scale runs 55% to 100%. Rows with fewer than 30 flights show a dash.

The 8pm–5am window is where this operation falls apart: 64.8% on time, against 94.0% for the 5am–8am slot. By evening the aircraft flying these rotations have absorbed a full day of small delays and there is no slack left to recover in. The 11am–2pm window is the busiest, with 5,648 flights scheduled in it.

Across the year

Seasonal pattern

Darker means more delays. Figures are on-time percentages.January best, June worst

June is the worst month at 66.8% on time, 21 points below January, the best at 88.0%. Summer afternoon convection and peak-season schedules land on the same weeks every year, so this is a pattern you can book around rather than a run of bad luck. July was the busiest month here, with 2,634 flights.

Delay causes

What holds this operation up

Late-arriving aircraft
50%
Carrier
34%
National Airspace System
15%
Extreme weather
1%
Security
0%

50% of delay minutes trace back to a late-arriving aircraft, meaning the plane was already behind before it got here. That is a cascade, and cascades start small and grow through the day. Across 300,000 reported delay minutes here, that single category outweighs weather by 50 to one. It is the strongest argument for booking the first departure of the morning, when the aircraft has been sitting at the gate overnight with nothing to inherit. The split is drawn from 300,257 reported delay minutes.

Cancellations are rare at 0.59%, below the national 1.81% 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.

5.4% of arrivals land an hour or more late, close to the national 8.1%. That is the figure that decides a connection, and it says a 60 to 75 minute layover is reasonable here while anything under 45 minutes is a bet. Most delays on this route are the about 50 minutes kind, which a normal layover absorbs.

28,173 flights sit behind these numbers, which is a large enough sample that the headline rate is not moving on noise. Where a sub-group falls below 30 flights the site shows a dash instead of a percentage.

Put together: the calendar is the biggest lever here, not the carrier or the hour. January runs 88.0% on time and June 66.8%, a swing of 21 points. If the dates move at all, move them out of June before you think about anything else. 27,960 completed flights over 12 months sit behind that.

Common questions

Southwest Airlines at OAK

How often is Southwest Airlines at OAK delayed?

About one flight in five arrive at least 15 minutes late, which is the Department of Transportation's definition of a delayed arrival. That works out to 21.5% of the 28,173 flights in this analysis, against 22.4% nationally. Delayed flights are late by about 50 minutes on average.

Which airline is most reliable on Southwest Airlines at OAK?

SkyWest Airlines leads at 89.3% on time across 1,462 flights. Southwest Airlines is at the other end on 78.5%, a gap of 11 points. Sample size matters as much as the percentage: a rate built from a few hundred flights moves around far more than one built from ten thousand.

What time of day has the fewest delays on Southwest Airlines at OAK?

The 5am–8am departure window is the strongest at 94.0% on time. The 8pm–5am window is the weakest at 64.8%, 29 points behind. Later departures inherit delays from earlier flights the same aircraft has already flown, which is why the curve slopes the way it does.

How bad are June delays on Southwest Airlines at OAK?

June is the weakest month at 66.8% on time, compared with 88.0% in January. Across the year that is 21 points between the best and worst months. Moving flexible dates out of that month is one of the few things that reliably helps.

Where to go next

Source: US DOT Bureau of Transportation Statistics, on-time performance data, July 2025 to June 2026. Updated monthly. How this data is collected.

Key figures