Flight number record

UA 505

United Airlines · San Francisco to Houston

Route: SFO → IAH
Departs: 23:59
Flights: 327
Period: July 2025 to June 2026

Historical statistics for July 2025 to June 2026, not live status. For today’s UA 505, check with United Airlines.

UA 505 lands a B+, 6 points better than the national rate of 77.6%. About one flight in six arrives 15 minutes late or worse, and those flights are late by about an hour on average. That is a workable record, not a spotless one. That rests on 327 flights, with a median arrival 5 minutes early.

Set against the rest of the country, UA 505's record is 6 points better than the US average of 77.6%. That gap is worth roughly 58 fewer late arrivals for every thousand flights.

On time

83.4%

Arrivals under 15 minutes late, of 325 completed flights

Avg delay

62 min

Across delayed arrivals only, not all flights

Cancelled

0.31%

National rate is 1.81%

1 hour+ late

4.9%

National rate is 8.1%

These figures cover 327 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 505 flies

UA 505 is scheduled to leave San Francisco (SFO) at 23:59 local time and reach Houston (IAH) at 05:46. That slot held for 327 of the 327 scheduled departures in the data, so the figures below describe one steady operation rather than a number that moved around the clock.

Departs 23:59327 flights100.0%

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 23:59 departure sits in the 8pm–5am window. Across every US flight scheduled in that window the on-time rate is 70.5%, and UA 505 runs 13 points better at 83.4%. By that time of day most aircraft have flown several legs already, and whatever went wrong earlier is still in the schedule.

Against the route

UA 505 next to SFO to IAH

Every carrier on SFO to IAH combined arrived on time 84.8% of the time across 3,600 flights, so UA 505 is about level with it. Across its whole network United Airlines managed 79.0%, which this flight beats by 4 points.

UA 505 against its route and carrier
Compared with	Flights	On time	Avg delay	Cancelled	Grade
UA 505thin sample	327	83.4%	62 min	0.31%	B+
All United Airlines on SFO–IAH	3,600	84.8%	53 min	0.28%	B+
All carriers on SFO–IAH	3,600	84.8%	53 min	0.28%	B+
United Airlines, whole network	821,041	79.0%	72 min	1.01%	B

Across the year

UA 505 quarter by quarter

Quarter by quarter UA 505 held fairly steady: 84.8% in Jul–Sep 2025, 81.3% in Oct–Dec 2025, 84.6% in Jan–Mar 2026 and 83.3% in Apr–Jun 2026. A spread of 4 points is about what a sample of this size moves on its own, so the annual figure is a fair summary.

Jul–Sep 202592 flights84.8%
Oct–Dec 202591 flights81.3%
Jan–Mar 202653 flights84.6%
Apr–Jun 202691 flights83.3%

Scale runs 75% to 90%. Rows with fewer than 30 flights show a dash.

By weekday, UA 505 did best on Tuesday at 93.5% on time and worst on Wednesday at 76.1%. Each day rests on about 47 flights, so a gap of 17 points is worth noticing but could still narrow in another year.

Delay causes

Why UA 505 runs late

One category carries most of the weight here. Carrier accounts for 73% of the 3,319 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.

Carrier
73%
Late-arriving aircraft
19%
National Airspace System
6%
Extreme weather
2%

The largest share of delay minutes, 73%, 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 2,421 of the 3,319 delay minutes reported here. The split is drawn from 3,319 delay minutes reported on UA 505.

Cancellations are rare at 0.31%, 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 4.9% 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 1,635 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 four other city pairs in the data, including SAN to SFO (155), PHX to ORD (37) and ORD to SFO (19), but none flew often enough under UA 505 to report a rate for. Carriers move flight numbers between routes, so the figures on this page apply to SFO to IAH only.

One caution: this is a thin sample. 327 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 505

For a booking, read UA 505 as 83.4% on time with 0.31% cancelled over 327 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