Airport month record
ORDMAY
Chicago O'Hare International in May 2026
- Departures
- 33,733
- Month
- May 2026
- National, same month
- 78.6%
- Carriers
- 11
Historical statistics for May 2026, not live status or a forecast for this year’s May. For today’s conditions at ORD, see live FAA status.
ORD in May lands a B, 3 points worse than the national rate of 78.6%. About one flight in four arrives 15 minutes late or worse, and those flights are late by a little over an hour on average. That rests on 33,733 flights, of which Envoy Air flew 5,444 at 85.0% on time.
Envoy Air is the most reliable of the seven carriers covered here at 85.0% on time across 5,444 flights.
Key figures
On time
76.1%
Arrivals under 15 minutes late, of 33,292 completed departures
Avg delay
73 min
Across delayed arrivals only, not all flights
Cancelled
1.01%
Nationally in May: 0.92%
Whole year
70.8%
ORD across all twelve months
These figures cover 33,733 departures from Chicago O'Hare 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 ORD's other months
Against ORD's own year, May ran 5 points better than the twelve-month rate of 70.8%, which makes it number two of twelve months, best first. Cancellations were unusually low for ORD in May, at 1.01% against 2.80% across the year. Either side of it, April ran 69.7% on time and June 71.3%, so a trip moved by a few weeks would have landed in a worse stretch.
| Month | Flights | On time | Avg delay | Cancelled | Grade |
|---|---|---|---|---|---|
| September 2025 | 28,867 | 79.2% | 68 min | 0.42% | B+ |
| October 2025 | 31,096 | 74.7% | 64 min | 0.23% | C+ |
| November 2025 | 28,703 | 73.3% | 82 min | 5.59% | C− |
| December 2025 | 27,790 | 61.0% | 91 min | 2.53% | D |
| January 2026 | 25,131 | 67.4% | 79 min | 3.74% | C− |
| February 2026 | 25,538 | 73.7% | 67 min | 1.11% | C |
| March 2026 | 31,373 | 65.9% | 85 min | 5.71% | C− |
| April 2026 | 33,206 | 69.7% | 75 min | 3.54% | C− |
| May 2026 (this page) | 33,733 | 76.1% | 73 min | 1.01% | B |
| June 2026 | 31,374 | 71.3% | 80 min | 3.19% | C− |
| July 2026 | 33,010 | 71.4% | 85 min | 4.18% | C− |
| August 2026 | 33,187 | 64.6% | 87 min | 2.31% | D |
Departure window
The best time of day to leave ORD in May
Departure time matters more here than the choice of carrier. The gap between the best and worst window is 19 points, against 24 points between the best and worst carrier.
- 5am–8am3,886 flights86.9%
- 8am–11am6,947 flights83.1%
- 11am–2pm5,390 flights77.9%
- 2pm–5pm6,699 flights71.7%
- 5pm–8pm5,316 flights67.8%
- 8pm–5am5,495 flights70.9%
Scale runs 60% to 90%.
Book the early departure. Flights leaving between 5am–8am arrive on time 86.9% of the time, against 67.8% for the evening window. That is 19 points of difference for no extra money, and it comes from the same aircraft having had no earlier flight to fall behind on. The 8am–11am window is the busiest, with 6,947 flights scheduled in it.
Across the week, Saturday is the strongest day at 84.0% on time and Monday the weakest at 65.0%, a spread of 19 points.
Carrier by carrier
Which airlines ran best at ORD in May
The choice of carrier is not cosmetic here. Envoy Air arrives on time 85.0% of the time; Southwest Airlines manages 60.7%. Sample sizes sit next to every figure, because a two-point gap across 403 flights means less than a ten-point one.
| Airline | Flights | On time | Avg delay | Cancelled | Grade |
|---|---|---|---|---|---|
| United Airlines | 9,414 | 76.5% | 72 min | 0.38% | B+ |
| SkyWest Airlines | 7,817 | 71.2% | 75 min | 1.59% | C |
| American Airlines | 6,084 | 70.2% | 81 min | 0.89% | C+ |
| Envoy Air | 5,444 | 85.0% | 58 min | 1.23% | A |
| Republic Airways | 2,763 | 84.5% | 69 min | 1.34% | B |
| Delta Air Lines | 991 | 78.7% | 80 min | 1.41% | B |
| Southwest Airlines | 403 | 60.7% | 69 min | 0.50% | D+ |
| Frontier Airlinesthin sample | 318 | 71.1% | 85 min | 0.31% | C+ |
| Alaska Airlinesthin sample | 302 | 80.5% | 46 min | 0.00% | B+ |
| JetBlue Airwaysthin sample | 103 | 91.1% | 66 min | 1.94% | A |
| PSA Airlinesthin sample | 80 | 78.2% | 77 min | 2.50% | B |
The spread between Envoy and Southwest is 24 points, wide enough that it should decide the booking. On a hundred trips that is 24 more arrivals inside the on-time window.
Route by route
Busiest routes out of ORD in May
| Route | Flights | On time | Avg delay | Cancelled | Grade |
|---|---|---|---|---|---|
| ORD to LGA · New York | 996 | 73.4% | 82 min | 1.61% | C |
| ORD to BOS · Boston | 740 | 76.6% | 79 min | 0.41% | B+ |
| ORD to DFW · Dallas-Fort Worth | 630 | 69.6% | 90 min | 1.59% | C |
| ORD to DCA · Washington | 608 | 72.0% | 82 min | 1.15% | C |
| ORD to LAX · Los Angeles | 601 | 79.1% | 70 min | 0.50% | B+ |
| ORD to DTW · Detroit | 599 | 77.1% | 82 min | 1.50% | B |
| ORD to ATL · Atlanta | 597 | 76.4% | 82 min | 1.17% | B |
| ORD to DEN · Denver | 584 | 78.0% | 68 min | 0.00% | B+ |
| ORD to IND · Indianapolis | 572 | 80.6% | 64 min | 2.62% | B |
| ORD to MSP · Minneapolis | 570 | 78.2% | 79 min | 0.88% | B+ |
| ORD to SEA · Seattle | 562 | 73.1% | 50 min | 0.00% | C+ |
| ORD to SFO · San Francisco | 559 | 59.2% | 74 min | 0.36% | D+ |
| ORD to EWR · Newark | 552 | 81.5% | 92 min | 0.91% | B+ |
| ORD to IAH · Houston | 537 | 74.3% | 64 min | 0.00% | C+ |
| ORD to MKE · Milwaukee | 517 | 71.3% | 82 min | 0.97% | C+ |
| ORD to MCO · Orlando | 502 | 72.7% | 81 min | 0.40% | C+ |
| ORD to PHX · Phoenix | 499 | 75.7% | 80 min | 0.40% | B+ |
| ORD to BNA · Nashville | 497 | 74.7% | 72 min | 1.01% | C |
| ORD to PHL · Philadelphia | 492 | 78.4% | 103 min | 1.02% | B |
| ORD to LAS · Las Vegas | 482 | 72.0% | 77 min | 0.00% | C+ |
| ORD to CLE · Cleveland | 467 | 77.1% | 79 min | 1.71% | B |
| ORD to CMH · Columbus | 460 | 80.6% | 76 min | 1.09% | B |
| ORD to CVG · Cincinnati | 459 | 80.7% | 63 min | 1.96% | B |
| ORD to GRR · Grand Rapids | 418 | 78.3% | 80 min | 1.67% | B |
| ORD to CLT · Charlotte | 411 | 77.4% | 81 min | 0.97% | B+ |
Delay causes
What held ORD up in May
Late-arriving aircraft accounts for 46% of the 583,000 delay minutes carriers reported here, and the remaining four split what is left.
- 46%Late-arriving aircraft
- 27%Carrier
- 19%National Airspace System
- 9%Extreme weather
- 0%Security
46% of delay minutes trace back to a late-arriving aircraft, meaning the plane was already behind before it got here. Across 583,000 reported delay minutes here, that single category outweighs weather by 5 to one. The split is drawn from 582,859 reported delay minutes.
Cancellations sit at 1.01% against a national 0.92%, which is ordinary. Diversions add another 0.30%.
9.2% of arrivals land a full hour or more behind schedule, against 7.1% nationally. Ninety minutes is the honest minimum for a connection here, and two hours if the onward flight is on a separate ticket.
What to do with this
Flying from ORD in May
For a May trip through ORD: this is one of the better months to be flying from here, 76.1% on time with 1.01% cancelled. That is a base rate for the month as a whole; a single storm can still spoil a particular day.
Related
Where to go next
- Chicago O'Hare International (ORD), the whole year
- ORD in September79.2%
- ORD in October74.7%
- ORD in November73.3%
- ORD in December61.0%
- ORD in January67.4%
- ORD in February73.7%
- ORD in March65.9%
- ORD in April69.7%
- ORD in June71.3%
- ORD in July71.4%
- ORD in August64.6%
Source: US DOT Bureau of Transportation Statistics, on-time performance data, September 2025 to August 2026. Last updated ; recomputed monthly. How this data is collected.