ATIS Alerts Smart Flight Search
Find the flight least likely to be delayed
BetaWe rank real flight numbers by how often they flew and arrived on time over the last 12 months, adjusted for your travel month and departure time, then check nearby airports and calmer connections. US airlines and airports.
MIA → MDW
Miami to Chicago: 520 nonstop flights a year
On time (12 months)
73%
Cancelled
1.7%
avg delay 17 min
Best time to leave
Before 9 AM
89% on time vs 52% 3 to 6 PM
Most reliable airline
Frontier
75% chance on time
Lowest nonstop fare seen in the next two months: $167 (Southwest 3081 on 2026-11-05). 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 · Southwest 2984
6:05 AM → 8:20 AM3h 15m nonstop
Local times, typical schedule. Last flown 2026-05-29.
83%
chance on time
- On time (history)
- 91%
- Cancelled
- 0.0%
- Avg arrival delay
- 27 min
- Arrived on time 91% of the time (23 flights, Jun 2025 to May 2026).
- Leaves in this route's most on-time window (Before 9 AM: 89% on time; 3 to 6 PM: 52%).
- Departs outside MIA's trouble window (1 PM to 7 PM, when 49% of its 45 ground stops and delay programs started).
- Lands inside MDW's trouble window: 50% of its 30 ground stops and delay programs started between 7 AM and 1 PM.
Limited track record · 23 flights
Find Southwest 2984 fares Opens this date on Aviasales#2 · Frontier 2109
11:13 AM → 1:41 PM3h 28m nonstop
Local times, typical schedule. Last flown 2026-04-13.
79%
chance on time
- On time (history)
- 80%
- Cancelled
- 1.6%
- Avg arrival delay
- 16 min
- Arrived on time 80% of the time (60 flights, Jun 2025 to May 2026).
- Departs outside MIA's trouble window (1 PM to 7 PM, when 49% of its 45 ground stops and delay programs started).
- 73% of its delay minutes came from the plane arriving late from an earlier flight.
Moderate track record · 60 flights
Find Frontier 2109 fares Opens this date on Aviasales#3 · Southwest 1862
6:45 AM → 8:55 AM3h 10m nonstop
Local times, typical schedule. Last flown 2026-05-31. Same departure also flew as Southwest 3294, 2096; its record covers all of them.
79%
chance on time
- On time (history)
- 79%
- Cancelled
- 4.6%
- Avg arrival delay
- 15 min
- Arrived on time 79% of the time (62 flights, Jun 2025 to May 2026).
- Cancelled 4.6% of the time (3 of 65).
- Leaves in this route's most on-time window (Before 9 AM: 89% on time; 3 to 6 PM: 52%).
- Departs outside MIA's trouble window (1 PM to 7 PM, when 49% of its 45 ground stops and delay programs started).
Moderate track record · 62 flights
Find Southwest 1862 fares Opens this date on Aviasales#4 · Southwest 1352
6:05 PM → 8:25 PM3h 20m nonstop
Local times, typical schedule. Last flown 2026-05-31. Same departure also flew as Southwest 1497; its record covers all of them.
56%
chance on time
- On time (history)
- 47%
- Cancelled
- 0.0%
- Avg arrival delay
- 38 min
- Arrived on time 47% of the time (59 flights, Jun 2025 to May 2026).
- Never cancelled in 63 scheduled flights.
- Departs inside MIA's trouble window: 49% of its 45 ground stops and delay programs started between 1 PM and 7 PM.
- Short track record (59 flights), so its score leans on the airline's record at this hour.
Limited track record · 59 flights
Find Southwest 1352 fares Opens this date on Aviasales
Airlines on this route
Season-adjusted chance of operating and arriving on time.
- Frontier Airlines75%
64 flights · 78% on time as flown · 1.7% cancel
- Southwest Airlines71%
456 flights · 72% on time as flown · 1.7% cancel
On time by departure time
All airlines, scheduled local departure, Jun 2025 to May 2026.
- Before 9 AM89%
197 flights · avg delay 10 min
- 9 AM to noon79%
58 flights · avg delay 13 min
- Noon to 3 PM69%
117 flights · avg delay 15 min
- 3 to 6 PM52%
77 flights · avg delay 26 min
- 6 to 9 PM54%
69 flights · avg delay 37 min
Best day: Tuesday (80%). Worst: Saturday (69%).
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