Route profile
MDW→SLC
Flight reliability, delays and best times to fly from Chicago to Salt Lake City, 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 59% of comparable major US routes (4,598 compared)
Calculated from 2,016 flights. How this is calculated · What counts as on time
MDW → SLC arrives on time 76.6% of the time; the return trip, SLC → MDW, arrives on time 85.7% of the time, a 9.1-point gap between the two directions of the same city pair.
MDW → SLC spends 21.1 minutes on the ground on a 1,259-mile trip: 15.2 minutes from pushback to wheels-up at MDW and 5.9 minutes from touchdown to gate at SLC.
Source: US DOT Bureau of Transportation Statistics · Data covering July 2023 – July 2026
What stands out
Reliability on this route has fallen unusually sharply over the past year, a bigger swing than 93% of 5,368 comparable routes.
69.9% on time over the most recent 12 months (2025-08 to 2026-07), against 80.3% in the 12 months before (2024-08 to 2025-07), a change of 10.4 points.
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 5,368 in the comparison.
What sets this route apart
Where MDW to SLC differs most from similar routes by hour, weekday, month and airline, July 2023 – July 2026.
MDW to SLC is at its best against routes of similar length for flights scheduled at 9 AM: 88.6% arrive on time, 5.3 points ahead of the 83.3% those routes manage at that hour.
In June, MDW to SLC runs 7.2 points below routes of similar length, 64.8% on time to 72.0%. Against all other routes the gap is 7.9 points.
MDW to SLC against comparable routes
July 2023 – July 2026| Measure | This route | Compared with | Them | Gap | Flights behind it |
|---|---|---|---|---|---|
| Hour: 9 AM departures | 88.6% | routes of similar length | 83.3% | +5.3 pts | 210 here, 101,562 there |
| Month: June | 64.8% | routes of similar length | 72.0% | −7.2 pts | 165 here, 150,443 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
39 min late
against a median of 3 min early
Percentiles over 2,016 operations; cancelled and diverted flights are counted separately.
Will your connection be tight enough?
Layovers at SLC after arriving from MDW.
| Connection time | Chance of missing | Reads as |
|---|---|---|
| 30 min | 43% | Likely to miss |
| 45 min | 23% | High risk |
| 60 min | 13% | Some risk |
| 90 min | 5.5% | Some risk |
| 120 min | 2.7% | 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 1.04% of the time and diverts 0.15% of the time, which a late arrival never shows up in.
Chance of missing is the share of 1,992 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 39 minutes late (90th-percentile gate arrival delay), over 2,016 operations.
Any other layover length: connection checker.
Best time to fly
MDW → SLC flights departing 5–9 AM arrived on time 84.2% of the time, against 64.7% for 9 PM–5 AM departures, a gap of 19.5 percentage points.
By departure window
By departure hour
- 12 AM to 7 AM: too few flights to score
- 8 AM: 87.4% on time from 301 flights
- 9 AM: 88.6% on time from 214 flights
- 10 AM: 81.3% on time from 402 flights
- 11 AM to 7 PM: too few flights to score
- 8 PM: 71.6% on time from 138 flights
- 9 PM: 66.2% on time from 365 flights
- 10 PM: 62.2% on time from 224 flights
- 11 PM: too few flights to score
Departure windows with fewer than 120 flights are not scored.
Why MDW → SLC 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 MDW → SLC. Only delays of 15 minutes or more are attributed. What the five causes mean
Late-arriving aircraft is the largest cause on MDW → SLC, at 50.5%: flights here mostly leave late because the plane came in late, and the day shows it: 5–9 AM departures arrived on time 84.2% of the time and 9 PM–5 AM departures 64.7%.
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 | 2,016 | 76.6% | 1.04% | -3 min | 5.6% |
Weekly and seasonal patterns
By day of week
Saturday is historically the most reliable day and Sunday the least, a gap of 6.8 percentage points.
By month
- Jan: 79.6%
- Feb: 78.6%
- Mar: 75.3%
- Apr: 80.1%
- May: 75.3%
- Jun: 64.8%
- Jul: 66.7%
- Aug: 71.6%
- Sep: 86.1%
- Oct: 85.4%
- Nov: 85.4%
- Dec: 75.9%
June is historically the weakest month and September the strongest, a spread of 21.3 percentage points.
Reliability over time
July 2023 – July 2026
Over the most recent 12 months (2025-08 to 2026-07), on-time arrivals averaged 69.9% against 80.3% in the 12 months before — declining by 10.4 percentage points.
Data and methodology
Calculated by FlyerIntel from 2,016 MDW → SLC 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