Airport month record

SLCAUG

Salt Lake City International in August 2025

Departures: 9,985
Month: August 2025
National, same month: 77.4%
Carriers: 10

Historical statistics for August 2025, not live status or a forecast for this year’s August. For today’s conditions at SLC, see live FAA status.

SLC in August earns a B+. More than four flights in five arrive inside the 15-minute window the DOT uses to define an on-time arrival, which puts it 7 points better than the national rate of 77.4%. When something does go wrong the average delay runs about an hour. That rests on 9,985 flights, of which SkyWest Airlines flew 3,122 at 92.6% on time.

SkyWest Airlines is the most reliable of the five carriers covered here at 92.6% on time across 3,122 flights.

On time

84.3%

Arrivals under 15 minutes late, of 9,906 completed departures

Avg delay

62 min

Across delayed arrivals only, not all flights

Cancelled

0.39%

Nationally in August: 1.08%

Whole year

84.8%

SLC across all twelve months

These figures cover 9,985 departures from Salt Lake City International in August 2025. On time means an arrival less than 15 minutes after the scheduled gate time, the DOT's threshold, and the national comparison uses every US departure in the same month rather than the whole year.

Against the year

August next to SLC's other months

Against SLC's own year, August ran level with the twelve-month rate of 84.8%, which makes it number nine of twelve months, best first. Cancellations were unusually low for SLC in August, at 0.39% against 0.76% across the year. Either side of it, July ran 79.5% on time and September 88.2%, so this month sits in line with its neighbours.

SLC month by month
Month	Flights	On time	Avg delay	Cancelled	Grade
July 2025	10,346	79.5%	69 min	0.67%	B+
August 2025 (this page)	9,985	84.3%	62 min	0.39%	B+
September 2025	9,344	88.2%	62 min	0.19%	A+
October 2025	9,841	85.7%	60 min	0.11%	A+
November 2025	9,197	86.5%	71 min	1.72%	A
December 2025	9,740	83.8%	64 min	0.84%	B+
January 2026	9,515	85.5%	66 min	1.79%	A
February 2026	9,167	85.5%	73 min	0.99%	A+
March 2026	10,632	85.8%	67 min	1.21%	A
April 2026	9,877	84.4%	60 min	0.38%	B+
May 2026	10,146	85.3%	57 min	0.42%	A+
June 2026	10,084	83.3%	64 min	0.48%	B+

Departure window

The best time of day to leave SLC in August

Departure time matters more here than the choice of carrier. The gap between the best and worst window is 12 points, against 21 points between the best and worst carrier. Each bar is the on-time rate for flights scheduled inside that window.

5am–8am739 flights90.4%
8am–11am2,092 flights89.7%
11am–2pm2,049 flights85.0%
2pm–5pm1,629 flights79.0%
5pm–8pm1,359 flights78.5%
8pm–5am2,117 flights83.7%

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

Book the early departure. Flights leaving between 5am–8am arrive on time 90.4% of the time, against 78.5% for the evening window. That is 12 points of difference for no extra money, and it comes from the same aircraft having had no earlier flight to fall behind on. The 8pm–5am window is the busiest, with 2,117 flights scheduled in it.

Across the week, Tuesday is the strongest day at 88.5% on time and Monday the weakest at 81.8%. 7 points is a smaller lever than departure hour, but it is free.

Carrier by carrier

Which airlines ran best at SLC in August

The choice of carrier is not cosmetic here. SkyWest Airlines arrives on time 92.6% of the time; American Airlines manages 71.6%. Sample sizes sit next to every figure, because a two-point gap across 385 flights means less than a ten-point one.

Carriers at SLC in August 2025
Airline	Flights	On time	Avg delay	Cancelled	Grade
Delta Air Lines	4,648	82.7%	66 min	0.19%	B+
SkyWest Airlines	3,122	92.6%	55 min	0.03%	A+
Southwest Airlines	924	79.2%	58 min	0.11%	B+
United Airlines	395	74.6%	53 min	1.27%	C
American Airlines	385	71.6%	66 min	3.64%	C−
Frontier Airlinesthin sample	225	72.4%	61 min	1.33%	C
Alaska Airlinesthin sample	143	63.6%	47 min	2.10%	D
JetBlue Airwaysthin sample	54	77.4%	91 min	1.85%	B
Spirit Airlinesthin sample	52	84.0%	94 min	3.85%	B−
Hawaiian Airlinesthin sample	31	83.3%	63 min	0.00%	B+

American Airlines cancels 3.6% of what it schedules here, the highest in the table. A cancelled flight never appears in an on-time rate, so read that column alongside the punctuality one rather than after it.

Route by route

Busiest routes out of SLC in August

Routes from SLC in August 2025
Route	Flights	On time	Avg delay	Cancelled	Grade
SLC to DEN · Denver	669	71.3%	67 min	0.45%	C+
SLC to PHX · Phoenix	429	85.9%	63 min	0.23%	A+
SLC to SEA · Seattle	409	72.0%	47 min	1.22%	C
SLC to DFW · Dallas-Fort Worththin sample	320	66.7%	75 min	3.12%	C−
SLC to LAX · Los Angelesthin sample	303	88.1%	62 min	0.33%	A+
SLC to SFO · San Franciscothin sample	295	81.6%	43 min	0.34%	B+
SLC to LAS · Las Vegasthin sample	294	80.2%	64 min	0.34%	B+
SLC to ORD · Chicagothin sample	260	76.7%	63 min	1.92%	B
SLC to ATL · Atlantathin sample	250	83.9%	67 min	0.40%	B+
SLC to PDX · Portlandthin sample	222	89.1%	65 min	0.45%	A+
SLC to SAN · San Diegothin sample	208	81.2%	43 min	0.00%	B+
SLC to SMF · Sacramentothin sample	189	82.5%	68 min	0.00%	B+
SLC to SJC · San Josethin sample	166	86.7%	51 min	0.00%	A+
SLC to IAH · Houstonthin sample	160	77.2%	47 min	0.62%	B+
SLC to BOI · Boisethin sample	155	86.5%	45 min	0.00%	A+
SLC to JFK · New Yorkthin sample	154	81.2%	81 min	0.00%	B+
SLC to OAK · Oaklandthin sample	150	90.0%	59 min	0.00%	A+
SLC to DTW · Detroitthin sample	147	86.4%	53 min	0.00%	A+
SLC to SNA · Santa Anathin sample	147	84.8%	68 min	0.00%	B+
SLC to GEG · Spokanethin sample	144	85.3%	119 min	0.69%	A+
SLC to AUS · Austinthin sample	142	84.5%	76 min	0.00%	B+
SLC to BUR · Burbankthin sample	140	83.6%	155 min	0.00%	B+
SLC to SGU · St. Georgethin sample	132	94.7%	87 min	0.00%	A+
SLC to MSP · Minneapolisthin sample	131	88.5%	44 min	0.00%	A+
SLC to LGB · Long Beachthin sample	127	93.7%	31 min	0.00%	A+

Delay causes

What held SLC up in August

One category carries most of the weight here. Carrier accounts for 52% of the 97,000 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.

Carrier
52%
Late-arriving aircraft
26%
National Airspace System
20%
Extreme weather
2%
Security
0%

The largest share of delay minutes, 52%, falls under carrier control: crew scheduling, maintenance, fuelling, baggage. Unlike weather, that is a management outcome, and it is the category where the gap between two carriers on the same schedule is genuinely earned. It accounts for 50,000 of the 97,000 delay minutes reported here. The split is drawn from 97,176 reported delay minutes.

Cancellations are rare at 0.39%, below the national 1.08% 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.

Badly late arrivals are rare here: only 4.9% land an hour or more behind schedule, against 8.2% 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.

What to do with this

Flying from SLC in August

For a August trip through SLC: expect 84.3% on time and 0.39% cancelled, going by August 2025. The 5am–8am window was the strongest part of the day.

Salt Lake City International (SLC), the whole year
SLC in July79.5%
SLC in September88.2%
SLC in October85.7%
SLC in November86.5%
SLC in December83.8%
SLC in January85.5%
SLC in February85.5%
SLC in March85.8%
SLC in April84.4%
SLC in May85.3%
SLC in June83.3%

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