Flights

A flight number is a slot in a carrier’s schedule, and two departures on the same route can perform very differently. FlyerIntel publishes a profile where a number has operated the same route at least 600 times and is still flying — 2,653 of them.

That is 2,224,330 recorded operations across 12 carriers and 1,087 airport pairs, July 2023 – July 2026. Each profile compares the number against the route it flies, which is the comparison that decides whether the slot is worth choosing.

Most reliable flights

Highest on-time arrival rate among the 2,653 numbers with a published profile.

Most reliable flights
Rank	Flight	Route	Operations	On time
1	OO3745	TUS → SLC	785	97.6%
2	DL886	TUS → ATL	785	96.9%
3	DL1535	PHX → SLC	785	96.8%
4	DL1270	PDX → SLC	785	96.7%
5	DL2369	PDX → MSP	779	96.3%
6	UA459	PDX → DEN	798	96.2%
7	DL2178	SFO → MSP	784	96.1%
8	UA1734	BOS → IAD	623	96.1%
9	DL2674	LAS → SLC	1,037	96.0%
10	UA2089	SJU → ORD	606	96.0%
11	UA2608	LAS → IAH	861	96.0%
12	DL1526	SMF → SLC	785	95.9%
13	DL2844	LAS → SEA	1,036	95.4%
14	DL1331	SFO → SLC	785	95.4%
15	DL1117	SAN → SLC	785	95.3%
16	WN4	HOU → DAL	659	95.2%
17	UA2022	SJU → IAD	674	95.2%
18	YX3679	PIT → IAD	793	95.2%
19	DL2221	BNA → MSP	1,127	95.2%
20	DL943	SEA → MSP	785	95.1%
21	AA548	JAX → CLT	621	95.1%
22	DL1019	BOS → DTW	785	95.1%
23	DL1344	AUS → ATL	1,127	95.0%
24	OO3743	SAN → LAX	1,051	95.0%
25	UA469	SAT → IAH	616	95.0%

Source: FlyerIntel analysis of US DOT BTS data · July 2023 – July 2026

Least reliable flights

The same list read from the other end.

Least reliable flights
Rank	Flight	Route	Operations	On time
1	F93216	LAX → ATL	610	45.9%
2	UA254	EWR → ORD	732	47.4%
3	AA662	DFW → DEN	788	47.6%
4	F94602	ATL → EWR	626	48.7%
5	AA2235	DFW → DEN	622	50.3%
6	AA2186	DFW → MCO	922	50.4%
7	B6998	MCO → LGA	631	51.1%
8	AA1322	DFW → DEN	1,078	51.1%
9	B61284	MCO → JFK	629	51.4%
10	AA446	DFW → SFO	775	52.3%
11	AA1771	DFW → LAS	841	52.9%
12	DL1454	DTW → DCA	766	52.9%
13	AA2791	DFW → MCO	768	52.9%
14	DL2498	ATL → EWR	843	53.0%
15	AA2810	DFW → SFO	607	53.4%
16	AA1060	CLT → LGA	633	53.6%
17	AA1430	DFW → SFO	1,017	53.9%
18	F93442	ATL → MIA	658	53.9%
19	F94462	PHL → SJU	742	54.2%
20	AA618	DFW → EWR	616	54.5%
21	AS16	SEA → JFK	1,077	54.5%
22	B6706	FLL → EWR	867	54.6%
23	DL2879	ATL → ORD	887	54.7%
24	AA577	DFW → DEN	1,050	54.9%
25	F91165	SJU → PHL	761	54.9%

Source: FlyerIntel analysis of US DOT BTS data · July 2023 – July 2026 · Ranked on arrivals, not departures: a flight that pushes back late and lands on time is not a late flight here. Every row cleared the same 600-operation floor as the table above.

What separates them

The same period, the same source, the same definition of late.

Among the 2,653 numbers with a published profile, on-time arrivals run from 97.6% on OO3745 down to 45.9% on F93216 — 51.7 percentage points between two departures held to the same standard over at least 600 operations each.

Neither end is a verdict on the airline. A flight number carries a time of day, a position in an aircraft’s rotation and a pair of airports, and those explain most of the gap — which is why every profile states the number’s figure against its own route rather than against the carrier.

Source: FlyerIntel analysis of US DOT BTS data · July 2023 – July 2026

Most frequently operated

Ordered by operations recorded on the route each number currently flies.

Most frequently operated
Rank	Flight	Route	Operations	On time
1	UA2088	SJU → ORD	1,127	74.8%
2	DL1510	ATL → MIA	1,127	81.3%
3	UA757	SEA → DEN	1,127	84.3%
4	AS1	DCA → SEA	1,127	85.6%
5	DL1854	SJU → JFK	1,127	93.9%
6	UA668	SJU → IAH	1,127	75.9%
7	UA2219	SJU → EWR	1,127	77.8%
8	DL1658	ATL → MCO	1,127	79.8%
9	DL2601	BWI → DTW	1,127	93.3%
10	UA1173	SJU → EWR	1,127	66.7%
11	DL1688	ABQ → ATL	1,127	93.2%
12	DL1030	ATL → MCO	1,127	78.8%
13	UA219	ORD → HNL	1,127	84.9%
14	AA162	HNL → LAX	1,127	84.0%
15	UA1996	ORD → SJU	1,127	82.0%
16	UA252	HNL → IAH	1,127	86.6%
17	UA383	HNL → DEN	1,127	88.2%
18	DL904	ATL → SMF	1,127	88.3%
19	DL1780	BOS → SJU	1,127	80.2%
20	AA1604	SAT → MIA	1,127	91.0%
21	DL2221	BNA → MSP	1,127	95.2%
22	DL1344	AUS → ATL	1,127	95.0%
23	DL480	LAX → HNL	1,127	83.5%
24	DL774	ATL → SEA	1,127	84.3%
25	AA31	LAX → HNL	1,127	85.4%

Source: FlyerIntel analysis of US DOT BTS data · July 2023 – July 2026

Every flight number, by airline

The lists above show the extremes. Each airline's directory lists all of its published flight numbers.

Delta Air Lines — 1,146 flight numbers
United Airlines — 360 flight numbers
American Airlines — 349 flight numbers
JetBlue — 301 flight numbers
Frontier Airlines — 165 flight numbers
Alaska Airlines — 122 flight numbers
Republic Airways — 113 flight numbers
SkyWest Airlines — 79 flight numbers
Southwest Airlines — 9 flight numbers (airline profile)
Envoy Air — 5 flight numbers (airline profile)
PSA Airlines — 3 flight numbers (airline profile)
Spirit Airlines — 1 flight numbers (airline profile)

Source: FlyerIntel analysis of US DOT BTS data · July 2023 – July 2026

Analysis last recomputed September 26, 2026