Carrier route record
OOORD→GSP
SkyWest Airlines · Chicago to Greer
- Flights
- 528
- Period
- July 2025 to June 2026
- Share of route
- 29%
- Carriers
- 6
Historical statistics for July 2025 to June 2026, not live status. For today’s flights, check with SkyWest Airlines.
SkyWest on ORD to GSP sits in the middle of the pack with a C−. About seven flights in ten arrive on time by the DOT's definition, 8 points worse than the national rate of 77.6%. The late ones land a little over an hour behind schedule. That rests on 528 flights, with a median arrival 2 minutes late.
The national on-time rate over the same period is 77.6%, so SkyWest on ORD to GSP runs 8 points behind the country as a whole. Across a thousand flights that is about 79 extra late arrivals.
Key figures
On time
69.7%
Arrivals under 15 minutes late, of 508 completed flights
Avg delay
69 min
Across delayed arrivals only, not all flights
Cancelled
3.60%
National rate is 1.81%
Whole route
72.9%
Every carrier on ORD to GSP, 1,799 flights
These figures cover 528 flights between July 2025 and June 2026. Beyond the headline rate, 9.6% of arrivals land a full hour or more behind schedule. That is the number that wrecks a connection, and it is not visible in an on-time percentage alone.
Carrier by carrier
SkyWest against every carrier on ORD to GSP
SkyWest flew 528 of the 1,799 flights on ORD to GSP, about 29% of it. Its 69.7% on time is 3 points worse than the route as a whole, which runs 72.9%. Ranked by on-time rate it is number four of six carriers on the route, where the range runs from United at 100.0% to PSA at 48.7%. Four of those carriers flew fewer than 365 flights here, so treat their positions as rough.
Only one carrier clears this site's 365-flight floor here, so there is no comparison to draw. The table below is the full picture.
| Airline | Flights | On time | Avg delay | Cancelled | Grade |
|---|---|---|---|---|---|
| United Airlinesthin sample | 1 | 100.0% | — | 0.00% | A+ |
| Republic Airwaysthin sample | 312 | 80.2% | 86 min | 4.49% | B− |
| Envoy Air | 778 | 76.7% | 61 min | 3.34% | B− |
| SkyWest Airlines (this page) | 528 | 69.7% | 69 min | 3.60% | C− |
| American Airlinesthin sample | 54 | 59.2% | 53 min | 9.26% | D− |
| PSA Airlinesthin sample | 126 | 48.7% | 122 min | 6.35% | F− |
Departure window
When SkyWest runs best on this route
Departure time matters more here than the choice of carrier. The gap between the best and worst window is 25 points, against half a point between the best and worst carrier. Each bar is the on-time rate for flights scheduled inside that window.
- 5am–8am69 flights80.9%
- 8am–11am45 flights60.0%
- 11am–2pm3 flights—
- 2pm–5pm278 flights73.1%
- 5pm–8pm112 flights55.7%
- 8pm–5am21 flights—
Scale runs 45% to 85%. Rows with fewer than 30 flights show a dash.
The 5pm–8pm window is where this operation falls apart: 55.7% on time, against 80.9% 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 2pm–5pm window is the busiest, with 278 flights scheduled in it.
Across the year
SkyWest on ORD to GSP through the year
January is the weak month at 54.8% on time, against 75.8% in June. Winter delays cluster: a single storm system can account for most of a month's shortfall, so an average December hides both very good weeks and genuinely unflyable days. May was the busiest month here, with 85 flights.
Across the week, Thursday is the strongest day at 77.0% on time and Sunday the weakest at 60.8%. 16 points is a smaller lever than departure hour, but it is free.
Delay causes
Why SkyWest runs late on this route
One category carries most of the weight here. Carrier accounts for 45% of the 11,000 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.
- 45%Carrier
- 22%National Airspace System
- 21%Late-arriving aircraft
- 13%Extreme weather
Extreme weather accounts for 13% 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 2.1 times the usual weather exposure. The split is drawn from 10,627 reported delay minutes.
The largest share of delay minutes, 45%, 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 4,742 of the 11,000 delay minutes reported here.
Cancellations run at 3.60%, against 1.81% nationally. That is about one flight in 30 cancelled outright. A cancelled flight is invisible in every on-time figure on this page, so the punctuality numbers above describe only the flights that actually operated.
Connections and stage length
What a delay here costs
For anyone connecting, the number to weigh is not the on-time rate but the tail behind it. 9.6% of arrivals land a full hour or more behind schedule, against 8.1% nationally. A 45-minute layover does not survive that, and no amount of walking quickly changes it. Ninety minutes is the honest minimum here, and two hours if the onward flight is on a separate ticket.
The 577 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 runs 70.4% on time across 527 flights, within half a point of this direction. The two legs are scored separately because they usually differ; on this city pair they happen not to.
One caution: this is a thin sample. 528 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 SkyWest on ORD to GSP
Put together: the delay figures matter less here than the 3.60% cancellation rate. A late arrival costs you a little over an hour; a cancelled flight costs you the day. Book the 5am–8am departure so there is still a schedule behind you if it goes wrong, and treat a same-day connection as optimistic. 508 completed flights over 12 months sit behind that.
Related
Where to go next
- ORD to GSP, every carrier
- SkyWest on GSP to ORD, the return leg
- Republic Airways on ORD to GSP80.2%
- Envoy Air on ORD to GSP76.7%
- PSA Airlines on ORD to GSP48.7%
- SkyWest Airlines network-wide record
- Chicago O'Hare International (ORD) delay statistics
- The US routes with the most cancellations
- What a cancellation rate actually tells you (and what it hides)
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.