1,310 nonstop flights · Aug 2025 – Jul 2026 · US DOT on-time records, all US airlines

United is clearly ahead here: 4 in 5 of its flights arrive on time, 23 points better than Frontier.

Best time to leave 8–9 am 87% arrive on time from SFO

Best single flight UA 552 SFO 21:00 → ONT 22:37 · 83% on time Avoid F9 2678 SFO 09:41 → ONT 11:13 · 58% on time

Time of day × airport

Share of this route’s flights leaving within 15 minutes, by airport and scheduled departure hour, over Aug 2025 – Jul 2026. Blank: no flights then (or fewer than 40 in the year).

SFO

% of this route’s flights leaving within 15 min (small number: flights in the Jun 6 – Jul 31, 2026 schedule): 85+75–8465–7455–64under 55

Ontario flights leaving SFO 9–10 am: 1Close ×


F9 2678	SFO 09:41	ONT 11:13	1h 34m	196	58%	3.1%	97 min

Airlines on this route

Arriving within 15 minutes. Regional flights count under the airline that sells them. Pick an airline to see its flights.


United (incl. SkyWest)	1,114	81%	0.5%	59 min
Frontier	196	58%	3.1%	97 min

Flights, best and worst

Flights in the Jun 6 – Jul 31, 2026 schedule that ran 150+ times in the year. Times are local. Pick a flight for its history.


UA 552	SFO 21:00	ONT 22:37	83%
UA 2661	SFO 10:40	ONT 12:12	78%
F9 2678	SFO 09:41	ONT 11:13	58%

All 4 flights on this route →

Nonstops by airline and airport

Arriving within 15 minutes, Aug 2025 – Jul 2026. Pick a row to see that airline’s flights on that airport pair.


United	SFO	ONT	1h 27m	81%	0.5%	1,114	Flying now
Frontier	SFO	ONT	1h 34m	58%	3.1%	196	Flying now

Flying on a particular day? Pick a date above and the same ranking uses our forecast odds for each flight that day: Tomorrow.

About this data: US DOT on-time records, Aug 2025 – Jul 2026, all US airlines; regional flights count under the airline that sells them. Schedules (which flights and connections exist, and their times) are as of Jun 6 – Jul 31, 2026; seasonal flights outside that window aren’t ranked. Rebuilt monthly. JSON