Cheapest return flights from Ontario to San Francisco in April from $59

Best time to book flights for Ontario (ONT) to San Francisco (SFO) flights at AirHint

AirHint found the following cheapest return flights from Ontario (ONT) to San Francisco (SFO) in April 2025 (see full year).

Return flights

17 Apr - 26 Apr Frontier Airlines direct
24 Apr - 26 Apr Frontier Airlines direct
14 Apr - 17 Apr Frontier Airlines direct
18 Apr - 20 Apr Frontier Airlines direct
04 Apr - 20 Apr Frontier Airlines direct
20 Apr - 27 Apr Frontier Airlines direct
11 Apr - 20 Apr Frontier Airlines direct
27 Apr - 04 May Frontier Airlines direct
10 Apr - 13 Apr Frontier Airlines direct
11 Apr - 13 Apr Frontier Airlines direct
13 Apr - 20 Apr Frontier Airlines direct
19 Apr - 11 May Southwest Airlines
29 Apr - 11 May Southwest Airlines
25 Apr - 03 May Southwest Airlines
29 Apr - 01 May Southwest Airlines
28 Apr - 05 May Southwest Airlines

Also check the deals for one-way flights from Ontario to San Francisco in April.

Skyscanner

The deals are updated regularly. The prices may go up as tickets are purchased by other travellers. Only the cheapest flights are offered. Select a price to book and secure these cheap prices.

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