Flight number record

OO 4134

SkyWest Airlines · Oakland to Salt Lake City

Route: OAK → SLC
Departs: 12:33
Flights: 365
Period: September 2025 to August 2026

Historical statistics for September 2025 to August 2026, not live status. For today’s OO 4134, check with SkyWest Airlines. SkyWest Airlines flies under contract for larger airlines, so a ticket for this flight may show a different airline code and number.

OO 4134 earns an A+. Nearly every flight arrives inside the 15-minute window the DOT uses to define an on-time arrival, which puts it 16 points better than the national rate of 77.3%. When something does go wrong the average delay runs about an hour. That rests on 365 flights, with a median arrival 13 minutes early.

Set against the rest of the country, OO 4134's record is 16 points better than the US average of 77.3%. That gap is worth roughly 164 fewer late arrivals for every thousand flights.

On time

93.7%

Arrivals under 15 minutes late, of 363 completed flights

Avg delay

61 min

Across delayed arrivals only, not all flights

Cancelled

0.55%

National rate is 1.89%

1 hour+ late

2.5%

National rate is 8.3%

These figures cover 365 flights between September 2025 and August 2026. The median arrival is 13 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.

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Schedule

When OO 4134 flies

OO 4134 flies OAK to SLC without a single fixed slot. Its most common scheduled departure was 12:33, used on 82 of 365 flights, with 12:30 (79 flights) and 12:28 (54 flights) next.

Departs 12:3382 flights22.5%
Departs 12:3079 flights21.6%
Departs 12:2854 flights14.8%

Scale runs 0% to 100%.

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

A 12:33 departure sits in the 11am–2pm window. Across every US flight scheduled in that window the on-time rate is 78.3%, and OO 4134 runs 15 points better at 93.7%. Midday slots inherit some of the morning's delays without yet carrying the full weight of the evening's.

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Against the route

OO 4134 next to OAK to SLC

Every carrier on OAK to SLC combined arrived on time 87.8% of the time across 1,621 flights, so OO 4134 is 6 points ahead of it. SkyWest flew 1,074 flights on the same city pair under all its flight numbers, including this one, and those ran 94.1% on time. Across its whole network SkyWest Airlines managed 78.7%, which this flight beats by 15 points.

OO 4134 against its route and carrier
Compared with	Flights	On time	Avg delay	Cancelled	Grade
OO 4134	365	93.7%	61 min	0.55%	A+
All SkyWest Airlines on OAK–SLC	1,074	94.1%	71 min	0.19%	A+
All carriers on OAK–SLC	1,621	87.8%	61 min	0.12%	A+
SkyWest Airlines, whole network	855,406	78.7%	88 min	1.79%	B

Across the year

OO 4134 quarter by quarter

Quarter by quarter OO 4134 held fairly steady: 96.7% in Jul–Sep 2025, 94.4% in Oct–Dec 2025, 88.9% in Jan–Mar 2026, 96.7% in Apr–Jun 2026 and 93.5% in Jul–Sep 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 202530 flights96.7%
Oct–Dec 202592 flights94.4%
Jan–Mar 202690 flights88.9%
Apr–Jun 202691 flights96.7%
Jul–Sep 202662 flights93.5%

Scale runs 80% to 100%.

By weekday, OO 4134 ranged from 88.5% on Sunday to 96.2% on Monday. With about 52 flights behind each day, a spread of 8 points is inside normal variation, so the day you fly is not worth changing for this flight.

Arrival by arrival

How late OO 4134 runs when it is late

OO 4134 often beats the schedule: 153 of 363 completed flights, 42%, arrived 15 minutes or more early. The 23 late arrivals split 6 under half an hour, 8 between 30 and 60 minutes, and 9 an hour or more.

15+ min early153 flights42.1%
Within 15 min187 flights51.5%
15–29 min late6 flights1.7%
30–59 min late8 flights2.2%
1–2 hours late8 flights2.2%
2+ hours late1 flights0.3%

Scale runs 0% to 100%.

Share of 363 completed flights by arrival against schedule.

8 of 30 late departures made up the time and arrived on time, 27% of them. Only 1 left on time and still arrived late.

The worst days

Worst days for OO 4134

The latest arrival of the period was on 25 January 2026, 3 hours 31 minutes behind schedule; most of its delay minutes were filed as carrier-caused (crew, maintenance, fuelling, baggage). The same cause led on four of the five worst days.

The latest arrivals of OO 4134 in the period
Date	Arrived late by	Largest filed cause
25 January 2026	3 hours 31 minutes	Carrier
18 February 2026	1 hour 48 minutes	Extreme weather
12 July 2026	1 hour 47 minutes	Carrier
11 July 2026	1 hour 44 minutes	Carrier
19 March 2026	1 hour 39 minutes	Carrier

Delay causes

Why OO 4134 runs late

Carrier accounts for 74% of the 1,407 delay minutes carriers reported here, and the remaining four split what is left.

Carrier
74%
Extreme weather
21%
National Airspace System
5%

Extreme weather accounts for 21% of delay minutes, well above the single-digit share typical across the system. Weather delays are lumpy: they arrive as whole bad days rather than as a steady drag, so the quarterly figures above are the more useful view of the risk. The national share is 6%, so this operation carries roughly 3.5 times the usual weather exposure. The split is drawn from 1,407 delay minutes reported on OO 4134.

Cancellations are rare at 0.55%, below the national 1.89% 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 2.5% land an hour or more behind schedule, against 8.3% 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 588 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.

OO 4134 is not only a OAK to SLC flight. It also flew SLC to OAK (365 flights, 92.6% on time) often enough to be scored on its own. Airlines attach one number to several legs of an aircraft's day, and each leg keeps its own record here, so check which city pair is on your booking before reading a rate.

One caution: this is a thin sample. 365 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.

Other routes flown as OO 4134
Also flown as	Flights	On time	Avg delay	Cancelled	Grade
SLC to OAK	365	92.6%	55 min	0.55%	A+

What to do with this

Booking OO 4134

For a booking, OO 4134 has one of the better records a US domestic flight can show: 93.7% on time and 0.55% cancelled. That is a base rate, not a promise about any single day.

Where to go next

A flight number here means SkyWest 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, September 2025 to August 2026. Last updated 22 October 2026; recomputed monthly. How this data is collected.

Key figures