Flight number record

UA 2117

United Airlines · San Diego to San Francisco

Route: SAN → SFO
Departs: 16:00
Flights: 359
Period: July 2025 to June 2026

Historical statistics for July 2025 to June 2026, not live status. For today’s UA 2117, check with United Airlines.

UA 2117 lands a B+, level with the national rate of 77.6%. Roughly one flight in five arrives 15 minutes late or worse, and those flights are late by roughly 50 minutes on average. That is a workable record, not a spotless one. That rests on 359 flights, with a median arrival 5 minutes early.

On time

78.2%

Arrivals under 15 minutes late, of 357 completed flights

Avg delay

52 min

Across delayed arrivals only, not all flights

Cancelled

0.56%

National rate is 1.81%

1 hour+ late

6.2%

National rate is 8.1%

These figures cover 359 flights between July 2025 and June 2026. The median arrival is 5 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 2117 flies

UA 2117 flies SAN to SFO without a single fixed slot. Its most common scheduled departure was 16:00, used on 149 of 359 flights, with 16:09 (41 flights) and 16:11 (37 flights) next. Carriers retime flights through the season, so the rates here blend slightly different positions in the aircraft's day.

Departs 16:00149 flights41.5%
Departs 16:0941 flights11.4%
Departs 16:1137 flights10.3%

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 16:00 departure sits in the 2pm–5pm window. Across every US flight scheduled in that window the on-time rate is 72.4%, and UA 2117 runs 6 points better at 78.2%. Midday slots inherit some of the morning's delays without yet carrying the full weight of the evening's.

Against the route

UA 2117 next to SAN to SFO

Every carrier on SAN to SFO combined arrived on time 65.0% of the time across 6,583 flights, so UA 2117 is 13 points ahead of it. United flew 2,598 flights on the same city pair under all its flight numbers, including this one, and those ran 70.6% on time. Across its whole network United Airlines managed 79.0%, close to this flight's figure.

UA 2117 against its route and carrier
Compared with	Flights	On time	Avg delay	Cancelled	Grade
UA 2117thin sample	359	78.2%	52 min	0.56%	B+
All United Airlines on SAN–SFO	2,598	70.6%	60 min	0.65%	C+
All carriers on SAN–SFO	6,583	65.0%	61 min	1.26%	C
United Airlines, whole network	821,041	79.0%	72 min	1.01%	B

Across the year

UA 2117 quarter by quarter

UA 2117 did not run the same all year. Its best quarter was Jul–Sep 2025 at 86.8% on time and its weakest Apr–Jun 2026 at 68.1%, a swing of 19 points on roughly 90 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 202592 flights86.8%
Oct–Dec 202586 flights76.5%
Jan–Mar 202690 flights81.1%
Apr–Jun 202691 flights68.1%

Scale runs 60% to 90%. Rows with fewer than 30 flights show a dash.

By weekday, UA 2117 did best on Saturday at 83.0% on time and worst on Thursday at 66.7%. Each day rests on about 51 flights, so a gap of 16 points is worth noticing but could still narrow in another year.

Delay causes

Why UA 2117 runs late

One category carries most of the weight here. Late-arriving aircraft accounts for 45% of the 4,088 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.

Late-arriving aircraft
45%
National Airspace System
39%
Carrier
15%
Extreme weather
1%

45% of delay minutes trace back to a late-arriving aircraft, meaning the plane was already behind before it got here. That is a cascade, and cascades start small and grow through the day. Across 4,088 reported delay minutes here, that single category outweighs weather by 45 to one. It is the strongest argument for booking the first departure of the morning, when the aircraft has been sitting at the gate overnight with nothing to inherit. The split is drawn from 4,088 delay minutes reported on UA 2117.

Cancellations are rare at 0.56%, 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

6.2% 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 roughly 50 minutes, which a normal layover absorbs.

The same number turns up on six other city pairs in the data, including SFO to ORD (74), SFO to EUG (52) and SFO to PIT (34), but none flew often enough under UA 2117 to report a rate for. Carriers move flight numbers between routes, so the figures on this page apply to SAN to SFO only.

One caution: this is a thin sample. 359 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 2117

For a booking, read UA 2117 as 78.2% on time with 0.56% cancelled over 359 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