Route profile
SLC→MDW
Flight reliability, delays and best times to fly from Salt Lake City to Chicago, 1,259 miles.
Right now
Aviation weather is not currently a factor.
Aviation weather is not currently a factor.
Route reliability
July 2023 – July 2026
Better than 97% of comparable major US routes (4,598 compared)
Calculated from 2,015 flights. How this is calculated · What counts as on time
SLC → MDW arrives on time 85.7% of the time; the return trip, MDW → SLC, arrives on time 76.6% of the time, a 9.1-point gap between the two directions of the same city pair.
SLC → MDW spends 20.0 minutes on the ground on a 1,259-mile trip: 15.2 minutes from pushback to wheels-up at SLC and 4.8 minutes from touchdown to gate at MDW.
Source: US DOT Bureau of Transportation Statistics · Data covering July 2023 – July 2026
What stands out
This route stays close to typical even on its worst days, a smaller gap than 96% of 4,598 comparable routes.
A typical arrival is 6 min early, and the worst tenth are only 27 minutes worse than that.
Source: FlyerIntel analysis of US DOT BTS data · July 2023 – July 2026 · Ranked against every other route with the same kind of figure and at least 4,598 in the comparison.
What sets this route apart
Where SLC to MDW differs most from similar routes by hour, weekday, month and airline, July 2023 – July 2026.
SLC to MDW is at its best against routes of similar length for flights scheduled at 8 AM: 96.9% arrive on time, 10.9 points ahead of the 86.0% those routes manage at that hour. Against all other routes the gap is 11 points.
SLC to MDW holds up on Mondays better than routes of similar length do: 88.0% on time to their 76.3%, a 11.7 points lead. Against all other routes the gap is 10.8 points.
July is kinder to SLC to MDW than to routes of similar length: 87.8% on time against 69.2%, 18.6 points better. Against all other routes the gap is 18.1 points.
Southwest Airlines does better on SLC to MDW than on its routes of similar length: 85.7% on time here, 75.6% there, 10.1 points apart. Against all other routes the gap is 8.3 points.
SLC to MDW against comparable routes
July 2023 – July 2026| Measure | This route | Compared with | Them | Gap | Flights behind it |
|---|---|---|---|---|---|
| Hour: 8 AM departures | 96.9% | routes of similar length | 86.0% | +10.9 pts | 128 here, 128,217 there |
| Weekday: Monday | 88.0% | routes of similar length | 76.3% | +11.7 pts | 299 here, 275,769 there |
| Month: July | 87.8% | routes of similar length | 69.2% | +18.6 pts | 230 here, 203,037 there |
| Airline: Southwest Airlines | 85.7% | routes of similar length | 75.6% | +10.1 pts | 1,989 here, 378,279 there |
Each comparison pools the flights of other routes, with this route’s own left out. Similar length means within 15% of this route’s 1,259 miles, with at least 5 such routes. A bucket is set against the most comparable group that has enough flights: similar length, then the same origin (at least 3 routes), then all other routes. Hours, weekdays and months appear only where both sides have 120 completed flights, and airlines where both have 600. The gap must be at least 2 points and 2 standard errors, and only the largest gap each way is kept per measure. These are differences in the flights counted, not causes.
When it goes wrong
July 2023 – July 2026
21 min late
against a median of 6 min early
Percentiles over 2,015 operations; cancelled and diverted flights are counted separately.
Will your connection be tight enough?
Layovers at MDW after arriving from SLC.
| Connection time | Chance of missing | Reads as |
|---|---|---|
| 30 min | 33% | Likely to miss |
| 45 min | 14% | Some risk |
| 60 min | 6.5% | Some risk |
| 90 min | 2.2% | Low risk |
| 120 min | 1.2% | Low risk |
This is one leg of a connection. Gate changes and the next flight's own schedule matter too. And a connection can fail before delay is even the question — this route cancels 0.60% of the time and diverts 0.69% of the time, which a late arrival never shows up in.
Chance of missing is the share of 1,989 arrivals on this route that landed later than the connection time less 30 minutes to reach the next gate.
The worst tenth of arrivals on this route land at least 21 minutes late (90th-percentile gate arrival delay), over 2,015 operations.
Any other layover length: connection checker.
Best time to fly
SLC → MDW flights departing 5–9 AM arrived on time 94.7% of the time, against 72.6% for 3–6 PM departures, a gap of 22.1 percentage points.
By departure window
By departure hour
- 12 AM to 4 AM: too few flights to score
- 5 AM: 95.4% on time from 416 flights
- 6 AM: 95.2% on time from 193 flights
- 7 AM: 92.6% on time from 300 flights
- 8 AM: 96.9% on time from 128 flights
- 9 AM to 12 PM: too few flights to score
- 1 PM: 75.6% on time from 315 flights
- 2 PM: 73.2% on time from 339 flights
- 3 PM: 74.2% on time from 151 flights
- 4 PM to 11 PM: too few flights to score
Departure windows with fewer than 120 flights are not scored.
Why SLC → MDW runs late
July 2023 – July 2026
the inbound aircraft was late, so this flight started late
crew, maintenance, boarding and fueling, all within the carrier’s control
airspace and airport capacity, including weather-driven flow control
weather severe enough to stop this flight specifically
screening or terminal security incidents
Share of the delay minutes US DOT attributed to each cause for SLC → MDW. Only delays of 15 minutes or more are attributed. What the five causes mean
Late-arriving aircraft is the largest cause on SLC → MDW, at 41.8%: flights here mostly leave late because the plane came in late, and the day shows it: 5–9 AM departures arrived on time 94.7% of the time and 3–6 PM departures 72.6%.
Airlines on this route
Carriers with at least 200 flights, by the airline that operated each one.
| Carrier | Flights | On time | Cancelled | Median delay | Severe |
|---|---|---|---|---|---|
| Southwest Airlines | 2,015 | 85.7% | 0.60% | -6 min | 2.2% |
Weekly and seasonal patterns
By day of week
Monday is historically the most reliable day and Tuesday the least, a gap of 5.4 percentage points.
By month
- Jan: 81.9%
- Feb: 88.3%
- Mar: 80.2%
- Apr: 85.2%
- May: 81.6%
- Jun: 79.8%
- Jul: 87.8%
- Aug: 85.3%
- Sep: 90.2%
- Oct: 90.6%
- Nov: 90.6%
- Dec: 87.0%
June is historically the weakest month and October the strongest, a spread of 10.8 percentage points.
Reliability over time
July 2023 – July 2026
Over the most recent 12 months (2025-08 to 2026-07), on-time arrivals averaged 83.6% against 88.2% in the 12 months before — declining by 4.6 percentage points.
Data and methodology
Calculated by FlyerIntel from 2,015 SLC → MDW flight records from the US DOT Bureau of Transportation Statistics, covering July 2023 – July 2026. Late means 15 or more minutes past scheduled arrival; cancelled and diverted flights are left out of on-time rates.
Full methodology · Data sources · Report a problem
Related research: How Long a Layover Needs to Be · Two Airlines on One Route · Best Time of Day to Fly From Major US Airports
Analysis last recomputed