Flight number record

UA 2343

United Airlines · San Diego to Chicago

Route: SAN → ORD
Departs: 07:00
Flights: 300
Period: July 2025 to June 2026

Historical statistics for July 2025 to June 2026, not live status. For today’s UA 2343, check with United Airlines.

UA 2343 earns an A. More than four flights in five arrive inside the 15-minute window the DOT uses to define an on-time arrival, which puts it 9 points better than the national rate of 77.6%. When something does go wrong the average delay runs a little over an hour. That rests on 300 flights, with a median arrival 4 minutes early.

Set against the rest of the country, UA 2343's record is 9 points better than the US average of 77.6%. That gap is worth roughly 85 fewer late arrivals for every thousand flights.

On time

86.1%

Arrivals under 15 minutes late, of 294 completed flights

Avg delay

80 min

Across delayed arrivals only, not all flights

Cancelled

1.00%

National rate is 1.81%

1 hour+ late

4.1%

National rate is 8.1%

These figures cover 300 flights between July 2025 and June 2026. The median arrival is 4 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 2343 flies

UA 2343 flies SAN to ORD without a single fixed slot. Its most common scheduled departure was 07:00, used on 163 of 300 flights, with 06:35 (49 flights) and 06:20 (32 flights) next. Carriers retime flights through the season, so the rates here blend slightly different positions in the aircraft's day.

Departs 07:00163 flights54.3%
Departs 06:3549 flights16.3%
Departs 06:2032 flights10.7%

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 2343 runs 3 points worse at 86.1%. 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 2343 next to SAN to ORD

Every carrier on SAN to ORD combined arrived on time 78.0% of the time across 3,807 flights, so UA 2343 is 8 points ahead of it. United flew 1,672 flights on the same city pair under all its flight numbers, including this one, and those ran 82.0% on time. Across its whole network United Airlines managed 79.0%, which this flight beats by 7 points.

UA 2343 against its route and carrier
Compared with	Flights	On time	Avg delay	Cancelled	Grade
UA 2343thin sample	300	86.1%	80 min	1.00%	A
All United Airlines on SAN–ORD	1,672	82.0%	76 min	0.54%	B+
All carriers on SAN–ORD	3,807	78.0%	81 min	1.34%	B
United Airlines, whole network	821,041	79.0%	72 min	1.01%	B

Across the year

UA 2343 quarter by quarter

Quarter by quarter UA 2343 held fairly steady: 82.3% in Jul–Sep 2025, 90.6% in Oct–Dec 2025, 85.0% in Jan–Mar 2026 and 86.0% in Apr–Jun 2026. A spread of 8 points is about what a sample of this size moves on its own, so the annual figure is a fair summary.

Jul–Sep 202580 flights82.3%
Oct–Dec 202586 flights90.6%
Jan–Mar 202684 flights85.0%
Apr–Jun 202650 flights86.0%

Scale runs 75% to 95%. Rows with fewer than 30 flights show a dash.

By weekday, UA 2343 did best on Wednesday at 97.4% on time and worst on Sunday at 77.8%. Each day rests on about 43 flights, so a gap of 20 points is worth noticing but could still narrow in another year.

Delay causes

Why UA 2343 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 3,295 reported delay minutes.

Carrier
42%
Late-arriving aircraft
31%
National Airspace System
27%

The largest share of delay minutes, 42%, 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 1,381 of the 3,295 delay minutes reported here. The split is drawn from 3,295 delay minutes reported on UA 2343.

Cancellations sit at 1.00% against a national 1.81%, which is ordinary. Diversions add another 1.00%.

Connections and routes

What a delay on this flight costs

Badly late arrivals are rare here: only 4.1% 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.

At 1,723 miles this is transcontinental flying, and long routes get a quiet structural advantage. Scheduled block time on a flight this length carries more padding in absolute minutes, so a twenty-minute late departure often still becomes an on-time arrival. Read the on-time rate here as slightly flattering next to a short-haul route with the same operational quality.

The same number turns up on nine other city pairs in the data, including ORD to IND (49), ORD to SYR (41) and SLC to ORD (35), but none flew often enough under UA 2343 to report a rate for. Carriers move flight numbers between routes, so the figures on this page apply to SAN to ORD only.

One caution: this is a thin sample. 300 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 2343

For a booking, UA 2343 has one of the better records a US domestic flight can show: 86.1% on time and 1.00% 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