Flight number record

UA 1421

United Airlines · Chicago to Fort Lauderdale

Route: ORD → FLL
Departs: 07:00
Flights: 341
Period: July 2025 to June 2026

Historical statistics for July 2025 to June 2026, not live status. For today’s UA 1421, check with United Airlines.

UA 1421 earns an A+. Close to nine flights in ten arrive inside the 15-minute window the DOT uses to define an on-time arrival, which puts it 14 points better than the national rate of 77.6%. When something does go wrong the average delay runs roughly 40 minutes. That rests on 341 flights, with a median arrival 9 minutes early.

Set against the rest of the country, UA 1421's record is 14 points better than the US average of 77.6%. That gap is worth roughly 135 fewer late arrivals for every thousand flights.

On time

91.1%

Arrivals under 15 minutes late, of 338 completed flights

Avg delay

42 min

Across delayed arrivals only, not all flights

Cancelled

0.59%

National rate is 1.81%

1 hour+ late

1.5%

National rate is 8.1%

These figures cover 341 flights between July 2025 and June 2026. The median arrival is 9 minutes early, which is the part an average hides: most flights here are fine, and the on-time rate is decided by a tail of badly late ones. On-time means under 15 minutes late, the DOT's own threshold.

Schedule

When UA 1421 flies

UA 1421 flies ORD to FLL without a single fixed slot. Its most common scheduled departure was 07:00, used on 252 of 341 flights, with 07:06 (53 flights) and 07:03 (36 flights) next. Carriers retime flights through the season, so the rates here blend slightly different positions in the aircraft's day.

Departs 07:00252 flights73.9%
Departs 07:0653 flights15.5%
Departs 07:0336 flights10.6%

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 07:00 departure sits in the 5am–8am window. Across every US flight scheduled in that window the on-time rate is 89.3%, and UA 1421 runs level with that at 91.1%. 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 1421 next to ORD to FLL

Every carrier on ORD to FLL combined arrived on time 72.8% of the time across 3,424 flights, so UA 1421 is 18 points ahead of it. United flew 1,478 flights on the same city pair under all its flight numbers, including this one, and those ran 78.5% on time. Across its whole network United Airlines managed 79.0%, which this flight beats by 12 points.

UA 1421 against its route and carrier
Compared with	Flights	On time	Avg delay	Cancelled	Grade
UA 1421thin sample	341	91.1%	42 min	0.59%	A+
All United Airlines on ORD–FLL	1,478	78.5%	67 min	0.81%	B+
All carriers on ORD–FLL	3,424	72.8%	78 min	2.10%	C
United Airlines, whole network	821,041	79.0%	72 min	1.01%	B

Across the year

UA 1421 quarter by quarter

UA 1421 did not run the same all year. Its best quarter was Jul–Sep 2025 at 98.9% on time and its weakest Apr–Jun 2026 at 88.2%, a swing of 11 points on roughly 85 flights a quarter. The twelve-month rate averages over that, so if you are flying in a weak quarter the quarter's own figure is the better guide.

Jul–Sep 202591 flights98.9%
Oct–Dec 202585 flights88.2%
Jan–Mar 202680 flights88.6%
Apr–Jun 202685 flights88.2%

Scale runs 80% to 100%. Rows with fewer than 30 flights show a dash.

By weekday, UA 1421 did best on Thursday at 96.2% on time and worst on Saturday at 82.7%. Each day rests on about 49 flights, so a gap of 14 points is worth noticing but could still narrow in another year.

Delay causes

Why UA 1421 runs late

One category carries most of the weight here. National Airspace System accounts for 52% of the 1,265 delay minutes carriers reported, and the remaining four split what is left. The split is by minutes rather than by flights, so a few very long delays count for as much as many short ones.

National Airspace System
52%
Carrier
41%
Extreme weather
4%
Late-arriving aircraft
4%

The largest share of delay minutes, 41%, falls under carrier control: crew scheduling, maintenance, fuelling, baggage. Unlike weather, that is a management outcome, and it is the category where the gap between two carriers on the same schedule is genuinely earned. It accounts for 514 of the 1,265 delay minutes reported here. The split is drawn from 1,265 delay minutes reported on UA 1421.

Cancellations are rare at 0.59%, below the national 1.81% 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.

Connections and routes

What a delay on this flight costs

Badly late arrivals are rare here: only 1.5% land an hour or more behind schedule, against 8.1% nationally. Connections built on this flight are about as safe as US domestic connections get, though a cancelled flight still ignores every layover you give it.

The 1,182 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 five other city pairs in the data, including FLL to IAD (97), FLL to EWR (19) and EWR to CHS (7), but none flew often enough under UA 1421 to report a rate for. Carriers move flight numbers between routes, so the figures on this page apply to ORD to FLL only.

One caution: this is a thin sample. 341 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 1421

For a booking, UA 1421 has one of the better records a US domestic flight can show: 91.1% on time and 0.59% cancelled. That is a base rate, not a promise about any single 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