Route reliability record
SLC→GEG
Salt Lake City to Spokane
- Flights
- 1,666
- Period
- July 2025 to June 2026
- Distance
- 546 mi
- Carriers
- 2
This route earns an A+. More than four flights in five arrive inside the 15-minute window the DOT uses to define an on-time arrival, which puts it 9 points better than the national rate of 77.6%. When something does go wrong the average delay runs a little over an hour. That rests on 1,666 SLC to GEG flights, of which SkyWest Airlines flew 739 at 92.9% on time.
Best time to fly SLC to GEG: a 8am–11am departure, ideally on a Wednesday. Flights in that window arrived on time 95.6% of the time and Wednesday flights 90.3%, against 86.7% for the route overall.
Set against the rest of the country, this route's record is 9 points better than the US average of 77.6%. That gap is worth roughly 91 fewer late arrivals for every thousand flights.
Key figures
On time
86.7%
Arrivals under 15 minutes late, of 1,651 completed flights
Avg delay
74 min
Across delayed arrivals only, not all flights
Cancelled
0.48%
National rate is 1.81%
Best carrier
SkyWest
92.9% on time across 739 flights
These figures cover 1,666 flights between July 2025 and June 2026. The median arrival is 8 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
Which airline is most reliable on SLC to GEG
The choice of carrier is not cosmetic here. SkyWest Airlines arrives on time 92.9% of the time; Delta Air Lines manages 81.8%. Sample sizes sit next to every figure, because a two-point gap across 927 flights means less than a ten-point one.
| Airline | Flights | On time | Avg delay | Cancelled | Grade |
|---|---|---|---|---|---|
| SkyWest Airlines | 739 | 92.9% | 57 min | 0.14% | A+ |
| Delta Air Lines | 927 | 81.8% | 80 min | 0.76% | B+ |
SkyWest leads Delta by 11 points. Real, but small enough that a better departure time on the weaker carrier can outweigh it.
Flight by flight
Flights on SLC to GEG
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.
Best ways to make this trip
The most reliable ways to fly Salt Lake City to Spokane
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. SLC → GEGSalt Lake City to Spokane | SkyWest Airlines | 92.8% | 92.9% | 0.14% | 8am–11am, Sat | — |
| 2. SLC → GEGSalt Lake City to Spokane | Delta Air Lines | 81.2% | 81.8% | 0.76% | 11am–2pm, Wed | DL 1452 11:15 |
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 15 points, against 11 points between the best and worst carrier. Each bar is the on-time rate for flights scheduled inside that window.
- 5am–8am—
- 8am–11am348 flights95.6%
- 11am–2pm364 flights85.3%
- 2pm–5pm347 flights84.8%
- 5pm–8pm243 flights87.7%
- 8pm–5am364 flights80.9%
Scale runs 70% to 100%. Rows with fewer than 30 flights show a dash.
Book the morning departure. Flights leaving between 8am–11am arrive on time 95.6% of the time, against 80.9% for the overnight window. That is 15 points of difference for no extra money, and it comes from the same aircraft having had no earlier flight to fall behind on. The 11am–2pm window is the busiest, with 364 flights scheduled in it.
Across the year
When delays peak on this route
Twelve months, one bar each, drawn from the same 1,666 flights. The strip shows how much of this route's record is set by the calendar rather than by the operation.
June is the worst month at 82.8% on time, 7 points below October, the best at 89.6%. 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. May was the busiest month here, with 149 flights.
Across the week, Wednesday is the strongest day at 90.3% on time and Sunday the weakest at 83.5%. 7 points is a smaller lever than departure hour, but it is free.
Delay causes
Why this route gets delayed
One category carries most of the weight here. Carrier accounts for 71% of the 16,000 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.
- 71%Carrier
- 14%Late-arriving aircraft
- 10%Extreme weather
- 6%National Airspace System
The largest share of delay minutes, 71%, 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 12,000 of the 16,000 delay minutes reported here. The split is drawn from 16,280 reported delay minutes.
Cancellations are rare at 0.48%, 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.
Connections and stage length
What a delay here actually costs
Badly late arrivals are rare here: only 4.0% 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 546 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 90.6% on time across 1,666 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.
The sample behind these figures is 1,666 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 GEG after this flight
What to do with this
Booking this route
Put together: avoid the 8pm–5am departure. It runs 80.9% on time against 95.6% for the 8am–11am slot, and that 15 points is the largest single thing you control here. SkyWest Airlines is the strongest operator if the fares are close. 1,651 completed flights over 12 months sit behind that.
Common questions
SLC to GEG questions
How often is SLC to GEG 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 13.3% of the 1,666 flights in this analysis, against 22.4% nationally. Delayed flights are late by a little over an hour on average.
Which airline is most reliable on SLC to GEG?
SkyWest Airlines leads at 92.9% on time across 739 flights. Delta Air Lines is at the other end on 81.8%, 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 SLC to GEG?
The 8am–11am departure window is the strongest at 95.6% on time. The 8pm–5am window is the weakest at 80.9%, 15 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 SLC to GEG?
June is the weakest month at 82.8% on time, compared with 89.6% in October. Across the year that is 7 points between the best and worst months. The seasonal swing is modest enough that it should not decide when you travel.
Related
Where to go next
- GEG to SLC — the return legseparate record
- Salt Lake City International (SLC) delay statistics
- SkyWest Airlines on SLC to GEG92.9%
- Delta Air Lines on SLC to GEG81.8%
- SLC to DEN, a related route77.8%
- SEA to GEG, a related route82.5%
- SLC to PHX, a related route83.9%
- SkyWest Airlines on-time record92.9%
- Delta Air Lines on-time record81.8%
- Same route, different airline: where the carrier you pick matters most
- The best time of day to fly, according to 7.04 million flight records
Direction matters. SLC to GEG and GEG to SLC 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, July 2025 to June 2026. Last updated 15 September 2026; recomputed monthly. How this data is collected.