Carrier route record

DLSEA→PSP

Delta Air Lines · Seattle to Palm Springs

Flights: 179
Period: July 2025 to June 2026
Share of route: 11%
Carriers: 3

Historical statistics for July 2025 to June 2026, not live status. For today’s flights, check with Delta Air Lines.

Delta on SEA to PSP lands a B, 5 points better than the national rate of 77.6%. About one flight in six arrives 15 minutes late or worse, and those flights are late by roughly 55 minutes on average. That is a workable record, not a spotless one. That rests on 179 flights. The strongest carrier on the route with a full sample, Alaska Airlines, flew 1,057 at 84.2% on time.

Set against the rest of the country, Delta's SEA to PSP record is 5 points better than the US average of 77.6%. That gap is worth roughly 53 fewer late arrivals for every thousand flights.

On time

82.9%

Arrivals under 15 minutes late, of 175 completed flights

Avg delay

53 min

Across delayed arrivals only, not all flights

Cancelled

2.23%

National rate is 1.81%

Whole route

83.9%

Every carrier on SEA to PSP, 1,653 flights

These figures cover 179 flights between July 2025 and June 2026. The median arrival is 5 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.

Carrier by carrier

Delta against every carrier on SEA to PSP

Delta flew 179 of the 1,653 flights on SEA to PSP, about 11% of it. Its 82.9% on time is about level with the route as a whole at 83.9%. Ranked by on-time rate it is last of three carriers on the route, where the range runs from Alaska at 84.2% to Delta at 82.9%.

The two carriers here are closely matched: half a point separate the best from the worst. At that spread, schedule and price are better tie-breakers than reliability. Sample sizes are shown so you can see which rows are worth weighing.

On-time performance by carrier on SEA to PSP
Airline	Flights	On time	Avg delay	Cancelled	Grade
Alaska Airlines	1,057	84.2%	47 min	0.66%	B+
SkyWest Airlines	417	83.5%	53 min	0.72%	B+
Delta Air Lines (this page)thin sample	179	82.9%	53 min	2.23%	B

No carrier stands out. Alaska tops the table at 84.2%, half a point clear of the bottom, which is inside the range this kind of sample moves year to year.

Departure window

When Delta runs best on this route

Departure time is the single lever a traveller controls, and it moves the odds more than most people expect. Each bar below is the on-time rate for flights scheduled to leave inside that window, across 179 flights.

There are not enough flights in each departure window to split Delta's SEA to PSP record by time of day without the percentages moving on noise. The headline rate of 82.9% is the reliable figure here.

Across the year

Delta on SEA to PSP through the year

Oct–Dec 202553 flights84.3%
Jan–Mar 202690 flights78.4%
Apr–Jun 202636 flights91.7%

Scale runs 70% to 95%. Rows with fewer than 30 flights show a dash.

Monthly volumes are too low here to break the year into twelve reliable readings. What the twelve-month total says is 82.9% on time across 179 flights.

Delta on SEA to PSP did not run the same all year. Its best quarter was Apr–Jun 2026 at 91.7% on time and its weakest Jan–Mar 2026 at 78.4%, a swing of 13 points on roughly 60 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.

Delay causes

Why Delta runs late on this route

One category carries most of the weight here. National Airspace System accounts for 50% of the 1,575 delay minutes carriers reported, and the remaining four split what is left. The split is by minutes rather than by flights, so a few very long delays count for as much as many short ones.

National Airspace System
50%
Carrier
18%
Extreme weather
17%
Late-arriving aircraft
15%

Extreme weather accounts for 17% of delay minutes, well above the single-digit share typical across the system. Weather delays are lumpy: they arrive as whole bad days rather than as a steady drag, so the monthly strip above is the more useful view of the risk. The national share is 6%, so this operation carries roughly 2.7 times the usual weather exposure. The split is drawn from 1,575 reported delay minutes.

50% 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 786 minutes out of 1,575, against a national NAS share of 21%.

Cancellations sit at 2.23% against a national 1.81%, which is ordinary. Diversions add another 0.00%.

Connections and stage length

What a delay here costs

Badly late arrivals are rare here: only 3.4% land an hour or more behind schedule, against 8.1% 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 987 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. It is also long enough that the aircraft usually flies three or four legs a day rather than six, which slows how fast delay compounds.

The return leg is a different operation and performs like one: it runs 86.9% on time across 179 flights, 4 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 4 points of difference.

One caution: this is a thin sample. 179 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 Delta on SEA to PSP

Put together: treat all of this as provisional. 179 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 82.9% headline is the most reliable number on the page; the hour and month splits below it are built on a few dozen flights each. 175 completed flights over 12 months sit behind that.

Where to go next

Source: US DOT Bureau of Transportation Statistics, on-time performance data, July 2025 to June 2026. Last updated 15 September 2026; recomputed monthly. How this data is collected.

Key figures