San Francisco to Ontario CA (SFO → ONT). We are tracking 12 fares on this route.
Cheapest tracked fare $24 · typical price $98 · you save about $74 (76%)
Cheapest fares we're tracking
Airline
Departs
Stops
Price
Frontier
2026-09-24
Direct
$24
Frontier Airlines
2026-11-12
Direct
$24
Frontier Airlines
2026-11-09
Direct
$24
Frontier Airlines
2026-09-18
Direct
$29
Frontier Airlines
2026-10-09
Direct
$30
Frontier Airlines
2026-10-23
Direct
$30
Frontier Airlines
2026-10-29
Direct
$31
Frontier Airlines
2026-11-13
Direct
$31
Frontier Airlines
2026-09-10
Direct
$34
Frontier Airlines
2026-10-22
Direct
$49
Frontier Airlines
2026-09-07
Direct
$61
Frontier Airlines
2026-11-26
Direct
$77
Could you save more?
The airport you were going to fly from is often not the cheapest one. Compare every airport in a region against each other, or check whether a multi-day stopover beats the direct fare.
How cheap can flights from San Francisco to Ontario CA get?
The cheapest fare we have tracked on this route is $24, compared with a typical $98 for a trip of this distance.
Is it cheaper to fly to Ontario CA from a different airport?
Often, yes. Fares out of secondary airports are frequently cheaper than the obvious hub, but they are the ones most likely to be missing from a normal search. Our reverse search compares every airport in a region against each other so the cheaper departure point is not hidden.
Could a stopover make San Francisco to Ontario CA cheaper?
Sometimes. On thin long-haul routes a two-leg trip with a multi-day stopover can beat the direct fare, and occasionally a direct fare is not sold at all. Our detour search prices those routings against the direct flight.