Airport month record
MDWMAY
Chicago Midway International in May 2026
- Departures
- 6,269
- Month
- May 2026
- National, same month
- 78.6%
- Carriers
- 3
Historical statistics for May 2026, not live status or a forecast for this year’s May. For today’s conditions at MDW, see live FAA status.
MDW in May sits in the middle of the pack with a C+. Close to three flights in four arrive on time by the DOT's definition, 5 points worse than the national rate of 78.6%. The late ones land roughly 55 minutes behind schedule. That rests on 6,269 flights, with a median arrival 2 minutes early.
The national on-time rate over the same period is 78.6%, so mdw in may runs 5 points behind the country as a whole. Across a thousand flights that is about 46 extra late arrivals.
Key figures
On time
74.0%
Arrivals under 15 minutes late, of 6,230 completed departures
Avg delay
53 min
Across delayed arrivals only, not all flights
Cancelled
0.35%
Nationally in May: 0.92%
Whole year
75.1%
MDW across all twelve months
These figures cover 6,269 departures from Chicago Midway International in May 2026. On time means an arrival less than 15 minutes after the scheduled gate time, the DOT's threshold, and the national comparison uses every US departure in the same month rather than the whole year.
Against the year
May next to MDW's other months
Against MDW's own year, May ran about a point worse than the twelve-month rate of 75.1%, which makes it number eight of twelve months, best first. Cancellations were unusually low for MDW in May, at 0.35% against 1.49% across the year. Either side of it, April ran 77.6% on time and June 64.2%, so a trip moved by a few weeks would have landed in a worse stretch.
| Month | Flights | On time | Avg delay | Cancelled | Grade |
|---|---|---|---|---|---|
| July 2025 | 7,531 | 67.2% | 69 min | 1.81% | C |
| August 2025 | 6,731 | 77.8% | 58 min | 0.74% | B+ |
| September 2025 | 6,459 | 84.1% | 46 min | 0.06% | B+ |
| October 2025 | 6,536 | 80.2% | 45 min | 0.17% | B+ |
| November 2025 | 5,620 | 80.6% | 59 min | 4.96% | B− |
| December 2025 | 5,738 | 69.7% | 57 min | 0.45% | C+ |
| January 2026 | 4,848 | 80.9% | 50 min | 2.15% | B |
| February 2026 | 4,537 | 81.6% | 46 min | 0.90% | B+ |
| March 2026 | 6,508 | 68.7% | 67 min | 3.89% | C− |
| April 2026 | 6,282 | 77.6% | 52 min | 1.18% | B |
| May 2026 (this page) | 6,269 | 74.0% | 53 min | 0.35% | C+ |
| June 2026 | 6,937 | 64.2% | 60 min | 1.53% | D |
Departure window
The best time of day to leave MDW in May
Departure time matters more here than the choice of carrier. The gap between the best and worst window is 35 points, against half a point between the best and worst carrier. Each bar is the on-time rate for flights scheduled inside that window.
- 5am–8am867 flights92.7%
- 8am–11am1,514 flights85.4%
- 11am–2pm1,057 flights75.3%
- 2pm–5pm826 flights65.6%
- 5pm–8pm1,165 flights62.2%
- 8pm–5am840 flights57.3%
Scale runs 50% to 100%. Rows with fewer than 30 flights show a dash.
The 8pm–5am window is where this operation falls apart: 57.3% on time, against 92.7% for the 5am–8am slot. By evening the aircraft flying these rotations have absorbed a full day of small delays and there is no slack left to recover in. The 8am–11am window is the busiest, with 1,514 flights scheduled in it.
Across the week, Friday is the strongest day at 79.6% on time and Monday the weakest at 61.1%. 18 points is a smaller lever than departure hour, but it is free.
Carrier by carrier
Which airlines ran best at MDW in May
Only one carrier clears this site's 365-flight floor here, so there is no comparison to draw. The table below is the full picture.
| Airline | Flights | On time | Avg delay | Cancelled | Grade |
|---|---|---|---|---|---|
| Southwest Airlines | 5,999 | 73.7% | 51 min | 0.33% | C+ |
| Delta Air Linesthin sample | 118 | 83.6% | 152 min | 0.85% | B+ |
| Frontier Airlinesthin sample | 106 | 77.1% | 77 min | 0.94% | B+ |
Route by route
Busiest routes out of MDW in May
| Route | Flights | On time | Avg delay | Cancelled | Grade |
|---|---|---|---|---|---|
| MDW to ATL · Atlantathin sample | 298 | 75.7% | 74 min | 0.34% | B+ |
| MDW to PHX · Phoenixthin sample | 235 | 77.6% | 71 min | 0.85% | B+ |
| MDW to LAS · Las Vegasthin sample | 202 | 78.6% | 57 min | 0.00% | B+ |
| MDW to LGA · New Yorkthin sample | 202 | 69.4% | 55 min | 2.48% | C |
| MDW to MCO · Orlandothin sample | 199 | 77.2% | 50 min | 0.50% | B+ |
| MDW to DAL · Dallasthin sample | 176 | 73.5% | 55 min | 1.70% | C |
| MDW to MCI · Kansas Citythin sample | 176 | 76.7% | 62 min | 0.00% | B+ |
| MDW to DCA · Washingtonthin sample | 176 | 61.9% | 49 min | 0.00% | D+ |
| MDW to BNA · Nashvillethin sample | 172 | 73.8% | 50 min | 0.00% | C+ |
| MDW to DEN · Denverthin sample | 163 | 76.5% | 55 min | 0.61% | B+ |
| MDW to STL · St. Louisthin sample | 156 | 79.2% | 50 min | 0.64% | B+ |
| MDW to HOU · Houstonthin sample | 150 | 65.3% | 44 min | 0.00% | C+ |
| MDW to MSP · Minneapolisthin sample | 149 | 83.8% | 56 min | 0.67% | B+ |
| MDW to BWI · Baltimorethin sample | 140 | 79.3% | 43 min | 0.00% | B+ |
| MDW to AUS · Austinthin sample | 131 | 75.4% | 53 min | 0.00% | B+ |
| MDW to TPA · Tampathin sample | 124 | 77.4% | 48 min | 0.00% | B+ |
| MDW to BOS · Bostonthin sample | 123 | 71.5% | 49 min | 0.00% | C+ |
| MDW to PHL · Philadelphiathin sample | 119 | 68.9% | 45 min | 0.00% | C+ |
| MDW to LAX · Los Angelesthin sample | 106 | 66.3% | 51 min | 0.00% | C+ |
| MDW to OMA · Omahathin sample | 106 | 76.4% | 46 min | 0.00% | B+ |
| MDW to SAN · San Diegothin sample | 105 | 68.0% | 44 min | 0.95% | C+ |
| MDW to FLL · Fort Lauderdalethin sample | 97 | 80.4% | 47 min | 0.00% | B+ |
| MDW to RSW · Fort Myersthin sample | 92 | 76.1% | 42 min | 0.00% | B+ |
| MDW to CMH · Columbusthin sample | 92 | 78.3% | 52 min | 0.00% | B+ |
| MDW to MSY · New Orleansthin sample | 92 | 67.4% | 46 min | 0.00% | C+ |
Delay causes
What held MDW up in May
Carriers report a reason for every delay minute they cause, in five DOT categories. The split below is by minutes, not by number of flights, so a handful of very long weather delays weighs as much as many short ones. It covers 86,000 reported delay minutes.
- 41%Late-arriving aircraft
- 39%Carrier
- 17%National Airspace System
- 2%Extreme weather
- 0%Security
41% of delay minutes trace back to a late-arriving aircraft, meaning the plane was already behind before it got here. That is a cascade, and cascades start small and grow through the day. Across 86,000 reported delay minutes here, that single category outweighs weather by 23 to one. It is the strongest argument for booking the first departure of the morning, when the aircraft has been sitting at the gate overnight with nothing to inherit. The split is drawn from 85,979 reported delay minutes.
Cancellations are rare at 0.35%, below the national 0.92% and low enough to earn the plus on the grade. Roughly one flight in 100 is called off; the risk here is arriving late, not not arriving.
6.9% of arrivals land an hour or more late, close to the national 7.1%. That is the figure that decides a connection, and it says a 60 to 75 minute layover is reasonable here while anything under 45 minutes is a bet. Most delays on this route last roughly 55 minutes, which a normal layover absorbs.
What to do with this
Flying from MDW in May
For a May trip through MDW: expect 74.0% on time and 0.35% cancelled, going by May 2026. The 5am–8am window was the strongest part of the day.
Related
Where to go next
- Chicago Midway International (MDW), the whole year
- MDW in July67.2%
- MDW in August77.8%
- MDW in September84.1%
- MDW in October80.2%
- MDW in November80.6%
- MDW in December69.7%
- MDW in January80.9%
- MDW in February81.6%
- MDW in March68.7%
- MDW in April77.6%
- MDW in June64.2%
Source: US DOT Bureau of Transportation Statistics, on-time performance data, July 2025 to June 2026. Last updated 15 September 2026; recomputed monthly. How this data is collected.