Route profile
MDW→SJC
Flight reliability, delays and best times to fly from Chicago to San Jose, 1,838 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 31% of comparable major US routes (4,598 compared)
Calculated from 1,707 flights. How this is calculated · What counts as on time
MDW → SJC arrives on time 70.4% of the time; the return trip, SJC → MDW, arrives on time 85.8% of the time, a 15.3-point gap between the two directions of the same city pair.
MDW → SJC spends 19.9 minutes on the ground on a 1,838-mile trip: 15.7 minutes from pushback to wheels-up at MDW and 4.2 minutes from touchdown to gate at SJC.
Source: US DOT Bureau of Transportation Statistics · Data covering July 2023 – July 2026
What sets this route apart
Where MDW to SJC differs most from similar routes by hour, weekday, month and airline, July 2023 – July 2026.
MDW to SJC struggles most at 3 PM: 54.1% of its flights scheduled then arrive on time, 18.8 points behind the 72.9% on routes of similar length at the same hour. Against all other routes the gap is 18.6 points.
Sunday is the day MDW to SJC slips furthest against routes of similar length, 64.1% on time where they average 75.4%, 11.3 points lower. Against all other routes the gap is 10.7 points.
In September, MDW to SJC runs 14.3 points below routes of similar length, 67.9% on time to 82.2%. Against all other routes the gap is 14.5 points.
Southwest Airlines’ flights on MDW to SJC arrive on time 70.4% of the time, 4.8 points below the 75.2% it manages on its routes of similar length. Against all other routes the gap is 7 points.
MDW to SJC against comparable routes
July 2023 – July 2026| Measure | This route | Compared with | Them | Gap | Flights behind it |
|---|---|---|---|---|---|
| Hour: 3 PM departures | 54.1% | routes of similar length | 72.9% | −18.8 pts | 133 here, 58,715 there |
| Weekday: Sunday | 64.1% | routes of similar length | 75.4% | −11.3 pts | 192 here, 178,630 there |
| Month: September | 67.9% | routes of similar length | 82.2% | −14.3 pts | 159 here, 96,483 there |
| Airline: Southwest Airlines | 70.4% | routes of similar length | 75.2% | −4.8 pts | 1,688 here, 196,172 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 1,838 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
51 min late
against a median of 1 min late
Percentiles over 1,707 operations; cancelled and diverted flights are counted separately.
Will your connection be tight enough?
Layovers at SJC after arriving from MDW.
| Connection time | Chance of missing | Reads as |
|---|---|---|
| 30 min | 50% | Likely to miss |
| 45 min | 28% | High risk |
| 60 min | 17% | High risk |
| 90 min | 8.3% | Some risk |
| 120 min | 4.4% | 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 0.70% of the time and diverts 0.41% of the time, which a late arrival never shows up in.
Chance of missing is the share of 1,688 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 51 minutes late (90th-percentile gate arrival delay), over 1,707 operations.
Any other layover length: connection checker.
Best time to fly
MDW → SJC flights departing 5–9 AM arrived on time 84.2% of the time, against 58.5% for 6–9 PM departures, a gap of 25.7 percentage points.
By departure window
By departure hour
- 12 AM to 7 AM: too few flights to score
- 8 AM: 85.6% on time from 270 flights
- 9 AM: 83.7% on time from 229 flights
- 10 AM: 74.3% on time from 227 flights
- 11 AM to 2 PM: too few flights to score
- 3 PM: 54.1% on time from 134 flights
- 4 PM: too few flights to score
- 5 PM: 74.6% on time from 144 flights
- 6 PM: too few flights to score
- 7 PM: 61.3% on time from 153 flights
- 8 PM: 52.9% on time from 281 flights
- 9 PM to 11 PM: too few flights to score
Departure windows with fewer than 120 flights are not scored.
Why MDW → SJC 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 → SJC. Only delays of 15 minutes or more are attributed. What the five causes mean
Late-arriving aircraft is the largest cause on MDW → SJC, at 46.5%: 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 6–9 PM departures 58.5%.
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 | 1,707 | 70.4% | 0.70% | 1 min | 8.5% |
Other ways to fly Chicago to San Francisco
Airport pairs in the same two city markets, as the DOT defines them.
| Route | Flights | On time | Cancelled | Median delay | Score |
|---|---|---|---|---|---|
| ORD→SFO Chicago to San Francisco | 16,116 | 71.8% | 1.14% | -3 min | 53 |
| MDW→SJC this route Chicago to San Jose | 1,707 | 70.4% | 0.70% | 1 min | 58 |
MDW → SJC is the most reliable pairing for this journey at 70.4% on time, against 71.8% for ORD → SFO.
Flying to SJC from the Chicago area? Compare MDW, ORD for SJC, with the same test for what counts as a real difference.
Weekly and seasonal patterns
By day of week
Tuesday is historically the most reliable day and Sunday the least, a gap of 9.1 percentage points.
Reliability over time
July 2023 – July 2026
Over the most recent 12 months (2025-08 to 2026-07), on-time arrivals averaged 68.7% against 76.8% in the 12 months before — declining by 8.1 percentage points.
Data and methodology
Calculated by FlyerIntel from 1,707 MDW → SJC 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