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Cheap flights from Ontario (ONT) to San Francisco (SFO)

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0 Children (2~11)
0 Infants (0~2)
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How to find the cheapest flight from Ontario (ONT) to San Francisco (SFO)

How to find the cheapest flight from Ontario (ONT) to San Francisco (SFO)
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How to find the cheapest flight from Ontario (ONT) to San Francisco (SFO)
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How to find the cheapest flight from Ontario (ONT) to San Francisco (SFO)
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Cheap flights from Ontario to San Francisco in December 2025 , January 2026

26 Dec - 05 Jan $ 138.00
ONT
Ontario
Frontier Airlines
DIRECT
SFO
San Francisco
SFO
San Francisco
Frontier Airlines
DIRECT
ONT
Ontario
Pick dates
25 Dec - 05 Jan $ 156.00
ONT
Ontario
Frontier Airlines
1 STOPS
SFO
San Francisco
SFO
San Francisco
Frontier Airlines
DIRECT
ONT
Ontario
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16 Dec - 19 Jan $ 495.00
ONT
Ontario
United Airlines
DIRECT
SFO
San Francisco
SFO
San Francisco
United Airlines
DIRECT
ONT
Ontario
Pick dates

Last minute flights from Ontario to San Francisco

28 Dec - 31 Dec $ 287.00
ONT
Ontario
Frontier Airlines
DIRECT
SFO
San Francisco
SFO
San Francisco
Frontier Airlines
1 STOPS
ONT
Ontario
Pick dates
25 Dec - 31 Dec $ 294.00
ONT
Ontario
Frontier Airlines
1 STOPS
SFO
San Francisco
SFO
San Francisco
Frontier Airlines
1 STOPS
ONT
Ontario
Pick dates
17 Dec - 31 Dec $ 572.00
ONT
Ontario
United Airlines
DIRECT
SFO
San Francisco
SFO
San Francisco
United Airlines
DIRECT
ONT
Ontario
Pick dates

One-way flights to San Francisco from Ontario

10:12 PM - 10:12 PM
Frontier Airlines
0 Stops
1h 40m
ONT - SFO
$ 94
Kiwi
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6:07 PM - 6:00 AM
Frontier Airlines
1 Stops
13h 41m
ONT - SFO
$ 112
Kiwi
Pick dates
6:41 PM - 6:41 PM
United Airlines
0 Stops
1h 24m
ONT - SFO
$ 353
Kiwi
Pick dates

How to find the cheapest flight from Ontario (ONT) to San Francisco (SFO)

Related info for your journey
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How to find the cheapest flight from Ontario (ONT) to San Francisco (SFO)
Some placeholder content for the first accordion panel. This panel is shown by default, thanks to the .show class.
How to find the cheapest flight from Ontario (ONT) to San Francisco (SFO)
Some placeholder content for the first accordion panel. This panel is shown by default, thanks to the .show class.