Route on-time record
LAS to ORD: most on-time flights and the best time to fly
Las Vegas (Harry Reid International Airport) to Chicago (Chicago O'Hare International Airport). 5,368 nonstop flights in Jun 2025 to May 2026, 77% arrived within 15 minutes and 1.1% were cancelled. The most reliable flight number was United 2102 at 11:59 PM.
Flying on a specific date? We’ll adjust for the month, the weekday and the forecast.
LAS → ORD
Las Vegas to Chicago: 5,368 nonstop flights a year
On time (12 months)
77%
Cancelled
1.1%
avg delay 19 min
Best time to leave
Before 9 AM
88% on time vs 62% noon to 3 PM
Most reliable airline
Spirit
82% chance on time
Fares open on our travel partner (Aviasales). Pick the flight number you chose here.
Most reliable nonstop flights
Ranked by the chance the flight operates and arrives within 15 minutes of schedule, from Jun 2025 to May 2026 records.
#1 · United 2102
11:59 PM → 5:37 AM3h 38m nonstop
Local times, typical schedule. Last flown 2026-05-31.
91%
chance on time
- On time (history)
- 92%
- Cancelled
- 0.3%
- Avg arrival delay
- 6 min
- Arrived on time 92% of the time (344 flights, Jun 2025 to May 2026).
- Departs outside LAS's trouble window (10 AM to 4 PM, when 51% of its 104 ground stops and delay programs started).
Strong track record · 344 flights
Find United 2102 fares Opens this date on Aviasales#2 · United 664
7:00 AM → 12:47 PM3h 47m nonstop
Local times, typical schedule. Last flown 2026-05-31.
91%
chance on time
- On time (history)
- 91%
- Cancelled
- 0.6%
- Avg arrival delay
- 10 min
- Arrived on time 91% of the time (349 flights, Jun 2025 to May 2026).
- Leaves in this route's most on-time window (Before 9 AM: 88% on time; Noon to 3 PM: 62%).
- Departs outside LAS's trouble window (10 AM to 4 PM, when 51% of its 104 ground stops and delay programs started).
Strong track record · 349 flights
Find United 664 fares Opens this date on Aviasales#3 · American 2258
6:00 AM → 11:51 AM3h 51m nonstop
Local times, typical schedule. Last flown 2026-05-31.
90%
chance on time
- On time (history)
- 92%
- Cancelled
- 1.2%
- Avg arrival delay
- 21 min
- Arrived on time 92% of the time (323 flights, Jun 2025 to May 2026).
- Leaves in this route's most on-time window (Before 9 AM: 88% on time; Noon to 3 PM: 62%).
- Departs outside LAS's trouble window (10 AM to 4 PM, when 51% of its 104 ground stops and delay programs started).
Strong track record · 323 flights
Find American 2258 fares Opens this date on Aviasales#4 · United 1672
7:03 PM → 12:50 AM3h 47m nonstop
Local times, typical schedule. Last flown 2026-05-31.
85%
chance on time
- On time (history)
- 100%
- Cancelled
- 0.0%
- Avg arrival delay
- 1 min
- Arrived on time 100% of the time (8 flights, Jun 2025 to May 2026).
- Departs outside LAS's trouble window (10 AM to 4 PM, when 51% of its 104 ground stops and delay programs started).
- Short track record (8 flights), so its score leans on the airline's record at this hour.
Limited track record · 8 flights
Find United 1672 fares Opens this date on Aviasales#5 · United 624
11:22 PM → 5:00 AM3h 38m nonstop
Local times, typical schedule. Last flown 2026-05-20. Same departure also flew as United 1995; its record covers all of them.
85%
chance on time
- On time (history)
- 84%
- Cancelled
- 0.0%
- Avg arrival delay
- 12 min
- Arrived on time 84% of the time (31 flights, Jun 2025 to May 2026).
- Never cancelled in 31 scheduled flights.
- Departs outside LAS's trouble window (10 AM to 4 PM, when 51% of its 104 ground stops and delay programs started).
- 53% of its delay minutes came from the plane arriving late from an earlier flight.
Limited track record · 31 flights
Find United 624 fares Opens this date on Aviasales#6 · United 1335
9:00 AM → 2:48 PM3h 48m nonstop
Local times, typical schedule. Last flown 2026-05-20.
84%
chance on time
- On time (history)
- 86%
- Cancelled
- 2.7%
- Avg arrival delay
- 14 min
- Arrived on time 86% of the time (72 flights, Jun 2025 to May 2026).
- Departs outside LAS's trouble window (10 AM to 4 PM, when 51% of its 104 ground stops and delay programs started).
- Lands inside ORD's trouble window: 44% of its 243 ground stops and delay programs started between 2 PM and 8 PM.
Moderate track record · 72 flights
Find United 1335 fares Opens this date on Aviasales#7 · United 1583
10:43 AM → 4:33 PM3h 50m nonstop
Local times, typical schedule. Last flown 2026-05-31.
84%
chance on time
- On time (history)
- 84%
- Cancelled
- 0.0%
- Avg arrival delay
- 12 min
- Arrived on time 84% of the time (215 flights, Jun 2025 to May 2026).
- Never cancelled in 218 scheduled flights.
- Departs inside LAS's trouble window: 51% of its 104 ground stops and delay programs started between 10 AM and 4 PM.
- Lands inside ORD's trouble window: 44% of its 243 ground stops and delay programs started between 2 PM and 8 PM.
Strong track record · 215 flights
Find United 1583 fares Opens this date on Aviasales#8 · American 2040
11:50 PM → 5:30 AM3h 40m nonstop
Local times, typical schedule. Last flown 2026-05-31.
82%
chance on time
- On time (history)
- 89%
- Cancelled
- 0.0%
- Avg arrival delay
- 3 min
- Arrived on time 89% of the time (9 flights, Jun 2025 to May 2026).
- Departs outside LAS's trouble window (10 AM to 4 PM, when 51% of its 104 ground stops and delay programs started).
- Short track record (9 flights), so its score leans on the airline's record at this hour.
Limited track record · 9 flights
Find American 2040 fares Opens this date on Aviasales#9 · American 2118
8:54 AM → 2:42 PM3h 48m nonstop
Local times, typical schedule. Last flown 2026-05-20.
82%
chance on time
- On time (history)
- 90%
- Cancelled
- 2.3%
- Avg arrival delay
- 5 min
- Arrived on time 90% of the time (42 flights, Jun 2025 to May 2026).
- Leaves in this route's most on-time window (Before 9 AM: 88% on time; Noon to 3 PM: 62%).
- Departs outside LAS's trouble window (10 AM to 4 PM, when 51% of its 104 ground stops and delay programs started).
- Lands inside ORD's trouble window: 44% of its 243 ground stops and delay programs started between 2 PM and 8 PM.
Limited track record · 42 flights
Find American 2118 fares Opens this date on Aviasales#10 · United 2320
4:07 PM → 10:03 PM3h 56m nonstop
Local times, typical schedule. Last flown 2026-05-31.
80%
chance on time
- On time (history)
- 91%
- Cancelled
- 0.0%
- Avg arrival delay
- 9 min
- Arrived on time 91% of the time (11 flights, Jun 2025 to May 2026).
- Departs outside LAS's trouble window (10 AM to 4 PM, when 51% of its 104 ground stops and delay programs started).
- Short track record (11 flights), so its score leans on the airline's record at this hour.
Limited track record · 11 flights
Find United 2320 fares Opens this date on Aviasales
Airlines on this route
Season-adjusted chance of operating and arriving on time.
- Spirit Airlines82%
324 flights · 84% on time as flown · 1.2% cancel
- United Airlines80%
2,332 flights · 80% on time as flown · 0.5% cancel
- American Airlines74%
1,817 flights · 76% on time as flown · 2.0% cancel
- Frontier Airlines68%
172 flights · 67% on time as flown · 3.0% cancel
- Southwest Airlines68%
723 flights · 67% on time as flown · 0.4% cancel
On time by departure time
All airlines, scheduled local departure, Jun 2025 to May 2026.
- Before 9 AM88%
1,116 flights · avg delay 13 min
- 9 AM to noon82%
1,102 flights · avg delay 14 min
- Noon to 3 PM62%
1,070 flights · avg delay 27 min
- 3 to 6 PM70%
1,125 flights · avg delay 24 min
- After 9 PM82%
865 flights · avg delay 17 min
Best day: Saturday (84%). Worst: Monday (76%).
On time by month
All airlines, Jun 2023 to May 2026. Several years per month, so one stormy season doesn't define a month. Travel-month estimates use this seasonal pattern.
What delays this route
- Late-arriving aircraft42%
- Air traffic control and airport volume29%
- Airline (crew, maintenance, boarding)27%
- Severe weather2%
Share of delay minutes by the cause airlines report to the US DOT.
Historical odds, not a guarantee. Built from the US DOT Bureau of Transportation Statistics on-time reports (Jun 2025 to May 2026), FAA ground stop and delay program advisories, and 20 years of airport weather observations. Covers US airlines that report to the DOT; schedules are flights operated recently, so confirm times when you book. ATIS Alerts is not affiliated with any airline. Fares are what Aviasales travelers saw in recent searches (USD, one way, 1 adult), not live quotes; the partner site shows the current price. Fare links go to our travel partner and may earn us a commission at no cost to you. Affiliate disclosure
LAS to ORD questions
- What time of day is best to fly LAS to ORD?
- Before 9 AM: 88% of flights arrived on time, against 62% for departures noon to 3 PM. Later flights inherit delays from earlier ones, so the first departures of the day usually run best.
- Which airline is most on time from LAS to ORD?
- Spirit, with a season-adjusted 82% chance of operating and arriving on time over 324 flights. The adjustment compares each airline with what the route did in the months it flew, so a carrier that skipped a stormy month gets no free credit.
- What is the worst month for delays on LAS to ORD?
- July (71% on time); the best was February (86%), averaged over Jun 2023 to May 2026.
- Is this a prediction for my flight?
- No. These are historical odds from the US DOT on-time reports, FAA advisories and airport weather records. Check your flight status and the FAA delay board on the day you fly.
More routes from LAS
- ORD to LAS (return)
- LAS to LAX 79%
- LAS to DEN 77%
- LAS to SAN 68%
- LAS to PHX 78%
- LAS to SFO 66%
- LAS to SEA 82%
- LAS to DFW 81%
- LAS to ATL 84%
- LAS to SNA 82%
- LAS to SMF 79%
- LAS to BUR 80%
- LAS to RNO 80%
Live status: FAA delays and ground stops