Carrier route record

UABWI→ORD

United Airlines · Baltimore to Chicago

Flights: 1,253
Period: September 2025 to August 2026
Share of route: 47%
Carriers: 8

Historical statistics for September 2025 to August 2026, not live status. For today’s flights, check with United Airlines.

United on BWI to ORD sits in the middle of the pack with a C. Close to three flights in four arrive on time by the DOT's definition, 3 points worse than the national rate of 77.3%. The late ones land an hour and a half behind schedule. That rests on 1,253 flights, with a median arrival 3 minutes early.

The US average over the same twelve months is 77.3%, so there is little to separate United on BWI to ORD from the country as a whole. The variation that matters here is internal: which carrier, and what time of day.

On time

74.3%

Arrivals under 15 minutes late, of 1,235 completed flights

Avg delay

86 min

Across delayed arrivals only, not all flights

Cancelled

1.12%

National rate is 1.89%

Whole route

75.5%

Every carrier on BWI to ORD, 2,677 flights

These figures cover 1,253 flights between September 2025 and August 2026. Beyond the headline rate, 9.3% of arrivals land a full hour or more behind schedule, against 8.3% nationally.

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Carrier by carrier

United against every carrier on BWI to ORD

United flew 1,253 of the 2,677 flights on BWI to ORD, about 47% of it. Its 74.3% on time is about level with the route as a whole at 75.5%. Ranked by on-time rate it is number six of eight carriers on the route, where the range runs from Southwest at 90.3% to American at 38.5%. Six of those carriers flew fewer than 365 flights here, so treat their positions as rough.

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.

On-time performance by carrier on BWI to ORD
Airline	Flights	On time	Avg delay	Cancelled	Grade
Southwest Airlinesthin sample	62	90.3%	59 min	0.00%	A+
Spirit Airlinesthin sample	10	90.0%	61 min	0.00%	A+
Republic Airwaysthin sample	336	83.0%	99 min	4.76%	B−
SkyWest Airlinesthin sample	17	76.5%	26 min	0.00%	B+
Envoy Air	841	76.0%	84 min	3.80%	B−
United Airlines (this page)	1,253	74.3%	86 min	1.12%	C
Frontier Airlinesthin sample	132	64.0%	199 min	4.55%	D−
American Airlinesthin sample	26	38.5%	81 min	0.00%	F+

Flight by flight

United flight numbers on BWI to ORD

UA 59017:3257.1% · 362 flights

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Departure window

When United runs best on this route

Departure time matters more here than the choice of carrier. The gap between the best and worst window is 32 points, against half a point between the best and worst carrier.

5am–8am298 flights89.2%
8am–11am262 flights82.6%
11am–2pm175 flights86.0%
2pm–5pm53 flights67.3%
5pm–8pm463 flights56.8%
8pm–5am2 flights—

Scale runs 50% to 95%. Rows with fewer than 30 flights show a dash.

The 5pm–8pm window is where this operation falls apart: 56.8% on time, against 89.2% 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 5pm–8pm window is the busiest, with 463 flights scheduled in it.

Across the year

United on BWI to ORD through the year

Darker means more delays. Figures are on-time percentages.September best, December worst

December is the weak month at 67.0% on time, against 81.0% in September. Winter delays cluster: a single storm system can account for most of a month's shortfall, so an average December hides both very good weeks and genuinely unflyable days. July was the busiest month here, with 148 flights.

Across the week, Saturday is the strongest day at 76.7% on time and Sunday the weakest at 69.3%, a spread of 7 points.

Arrival by arrival

How late United on BWI to ORD runs when it is late

The 317 late arrivals split 118 under half an hour, 84 between 30 and 60 minutes, and 115 an hour or more.

15+ min early275 flights22.3%
Within 15 min643 flights52.1%
15–29 min late118 flights9.6%
30–59 min late84 flights6.8%
1–2 hours late58 flights4.7%
2+ hours late57 flights4.6%

Scale runs 0% to 100%.

Share of 1,235 completed flights by arrival against schedule.

27 of 209 late departures made up the time and arrived on time, 13% of them. In the other direction, 135 flights left on time yet arrived 15 minutes late or more, so that delay built up after pushback: in the air, in a holding pattern or on the ground at ORD.

The worst days

Worst days for United on BWI to ORD

The latest arrival of the period was on 2 April 2026, 22 hours 11 minutes behind schedule; most of its delay minutes were filed as carrier-caused (crew, maintenance, fuelling, baggage). Three of the five worst days fell in April 2026.

The latest arrivals of United on BWI to ORD in the period
Date	Arrived late by	Largest filed cause
2 April 2026	22 hours 11 minutes	Carrier
17 April 2026	15 hours 54 minutes	Extreme weather
27 April 2026	13 hours 27 minutes	Extreme weather
14 December 2025	10 hours 12 minutes	Late-arriving aircraft
31 March 2026	9 hours 28 minutes	National Airspace System

Delay causes

Why United runs late on this route

National Airspace System accounts for 46% of the 27,000 delay minutes carriers reported here, and the remaining four split what is left.

National Airspace System
46%
Late-arriving aircraft
27%
Carrier
15%
Extreme weather
12%

Extreme weather accounts for 12% of delay minutes, well above the single-digit share typical across the system. Weather delays are lumpy: they arrive as whole bad days rather than as a steady drag, so the monthly strip above is the more useful view of the risk. The national share is 6%, so this operation carries roughly 2.1 times the usual weather exposure. The split is drawn from 27,195 reported delay minutes.

46% of delay minutes are charged to the National Airspace System: air traffic volume, runway configuration, ground stops. No carrier can price its way out of that, which is why airport choice moves the number here more than carrier choice does. That is 12,000 minutes out of 27,000, against a national NAS share of 21%.

Cancellations sit at 1.12% against a national 1.89%, which is ordinary. Diversions add another 0.32%.

Connections and stage length

What a delay here costs

9.3% of arrivals land a full hour or more behind schedule, against 8.3% nationally. Ninety minutes is the honest minimum for a connection here, and two hours if the onward flight is on a separate ticket.

The 622 miles between these two airports put this in the middle of the US network, around two and a half to three hours of block time. That is enough cruise to absorb a ten-minute late pushback and not enough to absorb thirty.

The return leg is a different operation and performs like one: it runs 70.3% on time across 1,257 flights, 4 points below this direction. Departure banks, aircraft rotations and the congestion at each end all differ, so scoring the two directions together would average away a real 4 points of difference.

The sample behind these figures is 1,253 flights, enough that the headline rate is stable to within roughly a point. The hour-block and month splits divide that further, so read the thinner bars with more caution than the headline.

What to do with this

Booking United on BWI to ORD

Put together: the calendar is the biggest lever here, not the carrier or the hour. September runs 81.0% on time and December 67.0%, a swing of 14 points. If the dates move at all, move them out of December before you think about anything else. 1,235 completed flights over 12 months sit behind that.

Where to go next

Source: US DOT Bureau of Transportation Statistics, on-time performance data, September 2025 to August 2026. Last updated 22 October 2026; recomputed monthly. How this data is collected.

Key figures