Flight number record

UA 1634

United Airlines · Dallas-Fort Worth to Chicago

Route: DFW → ORD
Departs: 10:10
Flights: 255
Period: July 2025 to June 2026

Historical statistics for July 2025 to June 2026, not live status. For today’s UA 1634, check with United Airlines.

UA 1634 lands a B, 3 points better than the national rate of 77.6%. About one flight in five arrives 15 minutes late or worse, and those flights are late by an hour and a half on average. That is a workable record, not a spotless one. That rests on 255 flights, with a median arrival 11 minutes early.

On time

81.0%

Arrivals under 15 minutes late, of 252 completed flights

Avg delay

88 min

Across delayed arrivals only, not all flights

Cancelled

1.18%

National rate is 1.81%

1 hour+ late

8.7%

National rate is 8.1%

These figures cover 255 flights between July 2025 and June 2026. Beyond the headline rate, 8.7% of arrivals land a full hour or more behind schedule. That is the number that wrecks a connection, and it is not visible in an on-time percentage alone.

Schedule

When UA 1634 flies

UA 1634 flies DFW to ORD without a single fixed slot. Its most common scheduled departure was 10:10, used on 68 of 255 flights, with 10:35 (49 flights) and 10:18 (31 flights) next. Carriers retime flights through the season, so the rates here blend slightly different positions in the aircraft's day.

Departs 10:1068 flights26.7%
Departs 10:3549 flights19.2%
Departs 10:1831 flights12.2%

Scale runs 0% to 100%. Rows with fewer than 30 flights show a dash.

Share of scheduled departures at each local time. Times used on fewer than one flight in ten are not listed.

A 10:10 departure sits in the 8am–11am window. Across every US flight scheduled in that window the on-time rate is 84.1%, and UA 1634 runs 3 points worse at 81.0%. Early departures usually start with an aircraft that has not flown yet that day, which is most of why the window does well.

Against the route

UA 1634 next to DFW to ORD

Every carrier on DFW to ORD combined arrived on time 67.6% of the time across 6,964 flights, so UA 1634 is 13 points ahead of it. United flew 2,010 flights on the same city pair under all its flight numbers, including this one, and those ran 71.7% on time. Across its whole network United Airlines managed 79.0%, which this flight beats by 2 points.

UA 1634 against its route and carrier
Compared with	Flights	On time	Avg delay	Cancelled	Grade
UA 1634thin sample	255	81.0%	88 min	1.18%	B
All United Airlines on DFW–ORD	2,010	71.7%	94 min	1.79%	C
All carriers on DFW–ORD	6,964	67.6%	83 min	3.19%	C−
United Airlines, whole network	821,041	79.0%	72 min	1.01%	B

Across the year

UA 1634 quarter by quarter

Quarter by quarter UA 1634 held fairly steady: 78.0% in Jul–Sep 2025, 84.3% in Oct–Dec 2025, 78.0% in Jan–Mar 2026 and 83.8% in Apr–Jun 2026. A spread of 6 points is about what a sample of this size moves on its own, so the annual figure is a fair summary.

Jul–Sep 202592 flights78.0%
Oct–Dec 202585 flights84.3%
Jan–Mar 202641 flights78.0%
Apr–Jun 202637 flights83.8%

Scale runs 70% to 90%. Rows with fewer than 30 flights show a dash.

By weekday, UA 1634 did best on Tuesday at 86.8% on time and worst on Monday at 71.1%. Each day rests on about 36 flights, so a gap of 16 points is worth noticing but could still narrow in another year.

Delay causes

Why UA 1634 runs late

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 4,236 reported delay minutes.

National Airspace System
41%
Late-arriving aircraft
29%
Carrier
22%
Extreme weather
9%

41% 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 1,717 minutes out of 4,236, against a national NAS share of 21%. The split is drawn from 4,236 delay minutes reported on UA 1634.

Cancellations sit at 1.18% against a national 1.81%, which is ordinary. Diversions add another 0.00%.

Connections and routes

What a delay on this flight costs

8.7% of arrivals land an hour or more late, close to the national 8.1%. 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 an hour and a half, which a normal layover absorbs.

The 802 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. It is also long enough that the aircraft usually flies three or four legs a day rather than six, which slows how fast delay compounds.

The same number turns up on twelve other city pairs in the data, including ORD to PHL (91), ORD to IAD (49) and ORD to SMF (37), but none flew often enough under UA 1634 to report a rate for. Carriers move flight numbers between routes, so the figures on this page apply to DFW to ORD only.

One caution: this is a thin sample. 255 flights over twelve months is enough to clear this site's floor but not enough to pin the rate down tightly, and a single bad week moves it by more than a point. Treat the grade as a rough reading.

What to do with this

Booking UA 1634

For a booking, read UA 1634 as 81.0% on time with 1.18% cancelled over 255 flights. Those are rates from the past twelve months, not a forecast for any particular day.

Where to go next

A flight number here means United Airlines’s own number as it reports to the DOT. How the figures are computed is on the methodology page.

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.

Key figures