Route reliability record
SMF→SLC
Sacramento to Salt Lake City
- Flights
- 2,165
- Period
- September 2025 to August 2026
- Distance
- 532 mi
- Carriers
- 3
This route 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 a little over an hour. That rests on 2,165 SMF to SLC flights, of which Delta Air Lines flew 1,503 at 88.9% on time.
Best time to fly SMF to SLC: a 5am–8am departure, ideally on a Saturday. Flights in that window arrived on time 96.2% of the time and Saturday flights 91.1%, against 87.0% for the route overall.
Set against the rest of the country, this route's 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 2,144 completed flights
Avg delay
74 min
Across delayed arrivals only, not all flights
Cancelled
0.88%
National rate is 1.89%
Best carrier
Delta
88.9% on time across 1,503 flights
These figures cover 2,165 flights between September 2025 and August 2026. The median arrival is 12 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.
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Carrier by carrier
Which airline is most reliable on SMF to SLC
The choice of carrier is not cosmetic here. Delta Air Lines arrives on time 88.9% of the time; Southwest Airlines manages 81.8%. Sample sizes sit next to every figure, because a two-point gap across 585 flights means less than a ten-point one.
| Airline | Flights | On time | Avg delay | Cancelled | Grade |
|---|---|---|---|---|---|
| SkyWest Airlinesthin sample | 77 | 90.9% | 60 min | 0.00% | A+ |
| Delta Air Lines | 1,503 | 88.9% | 82 min | 1.20% | A |
| Southwest Airlines | 585 | 81.8% | 63 min | 0.17% | B+ |
Delta leads Southwest by 7 points. Real, but small enough that a better departure time on the weaker carrier can outweigh it.
Flight by flight
Flights on SMF to SLC
The flight numbers below flew this route at least 250 times in the period, busiest first. Each has its own record, with its schedule and delay causes.
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Best ways to make this trip
The most reliable ways to fly Sacramento to Salt Lake City
Every airline on this route, ranked by how often a scheduled flight actually operated and arrived on time, with its best departure time and most punctual flight number. No nearby airport pair beat these.
| Option | Airline | Success | On time | Cancelled | Best departure | Most punctual flight |
|---|---|---|---|---|---|---|
| 1. SMF → SLCSacramento to Salt Lake City | Delta Air Lines | 87.8% | 88.9% | 1.20% | 5am–8am, Mon | DL 1526 05:30 |
| 2. SMF → SLCSacramento to Salt Lake City | Southwest Airlines | 81.7% | 81.8% | 0.17% | 8am–11am, Sat | — |
Success is the share of scheduled flights that operated and arrived less than 15 minutes late, so a cancelled flight counts against it. “(route)” means the best time comes from every carrier on the route rather than this airline alone.
Departure window
The best time of day to leave
Departure time matters more here than the choice of carrier. The gap between the best and worst window is 26 points, against 7 points between the best and worst carrier.
- 5am–8am445 flights96.2%
- 8am–11am552 flights92.5%
- 11am–2pm414 flights87.3%
- 2pm–5pm10 flights—
- 5pm–8pm628 flights78.3%
- 8pm–5am116 flights70.7%
Scale runs 60% to 100%. Rows with fewer than 30 flights show a dash.
Book the early departure. Flights leaving between 5am–8am arrive on time 96.2% of the time, against 70.7% for the overnight window. That is 26 points of difference for no extra money, and it comes from the same aircraft having had no earlier flight to fall behind on. The 5pm–8pm window is the busiest, with 628 flights scheduled in it.
Explore
Filter SMF to SLC by airline, time, month and day
Pick a breakdown and a carrier. The dashed mark on each row is the same slice for every US flight.
On SMF to SLC, the best departure window is 5am–8am at 96.2% on time and the worst is 8pm–5am at 70.7%, a wide gap of 25.5 points. All US flights leaving 5am–8am ran 89.3%.
- 5–8am96.2%
- 8–11am92.5%
- 11am–2pm87.3%
- 2–5pm—
- 5–8pm78.3%
- 8pm–5am70.7%
best all US flightsScale 60% to 100%. Cells under 30 flights show a dash.
Across the year
When delays peak on this route
Twelve months, one bar each, drawn from the same 2,165 flights. The strip shows how much of this route's record is set by the calendar rather than by the operation.
August is the worst month at 81.3% on time, 10 points below November, the best at 91.1%. 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 206 flights.
Across the week, Saturday is the strongest day at 91.1% on time and Friday the weakest at 83.1%, a spread of 8 points.
Delay causes
Why this route gets delayed
Late-arriving aircraft accounts for 58% of the 21,000 delay minutes carriers reported here, and the remaining four split what is left.
- 58%Late-arriving aircraft
- 37%Carrier
- 4%National Airspace System
- 1%Extreme weather
58% of delay minutes trace back to a late-arriving aircraft, meaning the plane was already behind before it got here. Across 21,000 reported delay minutes here, that single category outweighs weather by 58 to one. The split is drawn from 20,644 reported delay minutes.
The largest share of delay minutes, 37%, falls under carrier control: crew scheduling, maintenance, fuelling, baggage. It accounts for 7,607 of the 21,000 delay minutes reported here.
Cancellations are rare at 0.88%, 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 actually costs
5.2% of arrivals land an hour or more late, close to the national 8.3%, so a 60 to 75 minute layover is reasonable here while anything under 45 minutes is a bet. Most delays on this route last a little over an hour, which a normal layover absorbs.
The 532 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 runs 84.8% on time across 2,165 flights, within 2 points of this direction. The two legs are scored separately because they usually differ; on this city pair they happen not to.
The sample behind these figures is 2,165 flights, enough that the headline rate is stable to within roughly a point. The hour-block and month splits divide that further, so read the thinner bars with more caution than the headline.
Work out the risk of missing a connection in SLC after this flight
What to do with this
Booking this route
Put together: avoid the 8pm–5am departure. It runs 70.7% on time against 96.2% for the 5am–8am slot, and that 26 points is the largest single thing you control here. Delta Air Lines is the strongest operator if the fares are close. 2,144 completed flights over 12 months sit behind that.
Common questions
SMF to SLC questions
How often is SMF to SLC delayed?
About one flight in eight arrives at least 15 minutes late, which is the Department of Transportation's definition of a delayed arrival. That works out to 13.0% of the 2,165 flights in this analysis, against 22.7% nationally. Delayed flights are late by a little over an hour on average.
Which airline is most reliable on SMF to SLC?
Delta Air Lines leads at 88.9% on time across 1,503 flights. Southwest Airlines is at the other end on 81.8%, a gap of 7 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 SMF to SLC?
The 5am–8am departure window is the strongest at 96.2% on time. The 8pm–5am window is the weakest at 70.7%, 26 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 August delays on SMF to SLC?
August is the weakest month at 81.3% on time, compared with 91.1% in November. Across the year that is 10 points between the best and worst months. Moving flexible dates out of that month is one of the few things that reliably helps.
Related
Where to go next
- SLC to SMF — the return legseparate record
- Sacramento International (SMF) delay statistics
- Salt Lake City International (SLC) delay statistics
- Delta Air Lines on SMF to SLC88.9%
- Southwest Airlines on SMF to SLC81.8%
- SMF to LAX, a related route85.6%
- DEN to SLC, a related route78.2%
- SMF to SAN, a related route69.8%
- SkyWest Airlines on-time record90.9%
- Delta Air Lines on-time record88.9%
- Southwest Airlines on-time record81.8%
- Why the first flight of the morning is statistically safest
- The best time of day to fly, according to 7.05 million flight records
Direction matters. SMF to SLC and SLC to SMF are scored separately because they are separate operations, with different departure banks and different aircraft. Compare the return leg.
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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.