$28+ Cheap flights from Ontario (ONT) to the United States
This is the cheapest one-way flight price found by a Cheapflights user in the last 72 hours by searching for a flight departing on 8/19. Fares are subject to change and may not be available on all flights or dates of travel.
ONT — LAX
Aug 18 — Aug 251
Round-trip
1 adult, Economy
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Find cheap flights from Ontario to USA with Cheapflights
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Cheapest flights from Ontario to USAExplore the most affordable flight options available from Ontario to USA. Find the lowest fares from popular airlines and budget airlines, with prices last updated on July 19, 2026.
Explore the most affordable flight options available from Ontario to USA. Find the lowest fares from popular airlines and budget airlines, with prices last updated on July 19, 2026.
This Super.com deal was found by Cheapflights users on 7/15. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Super.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 10/111:38 am
ONT
- SFO
Nonstop1h 34m
Frontier
Thu 10/812:31 pm
SFO
- ONT
Nonstop1h 29m
Frontier
Deal found 7/15![Frontier logo]()
$84
This Trip.com deal was found by Cheapflights users on 7/18. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Trip.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 9/1111:38 am
ONT
- SFO
Nonstop1h 34m
Frontier
Mon 9/1412:31 pm
SFO
- ONT
Nonstop1h 29m
Frontier
Deal found 7/18![Frontier logo]()
$85
This Super.com deal was found by Cheapflights users on 7/19. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Super.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 8/158:58 am
ONT
- SFO
Nonstop1h 27m
Frontier
Wed 8/1912:33 pm
SFO
- ONT
Nonstop1h 30m
Frontier
Deal found 7/19![Frontier logo]()
$87
This Frontier deal was found by Cheapflights users on 7/19. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Frontier is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 8/118:58 am
ONT
- SFO
Nonstop1h 27m
Frontier
Tue 8/1812:33 pm
SFO
- ONT
Nonstop1h 30m
Frontier
Deal found 7/19![Frontier logo]()
$88
This Super.com deal was found by Cheapflights users on 7/19. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Super.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 8/88:58 am
ONT
- SFO
Nonstop1h 27m
Frontier
Wed 8/1211:15 am
SFO
- ONT
Nonstop1h 33m
Frontier
Deal found 7/19![Frontier logo]()
$89
This Frontier deal was found by Cheapflights users on 7/18. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Frontier is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 8/138:58 am
ONT
- SFO
Nonstop1h 27m
Frontier
Tue 8/1812:33 pm
SFO
- ONT
Nonstop1h 30m
Frontier
Deal found 7/18![Frontier logo]()
$90
This Super.com deal was found by Cheapflights users on 7/19. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Super.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 8/178:58 am
ONT
- SFO
Nonstop1h 27m
Frontier
Thu 8/209:00 am
SFO
- ONT
Nonstop1h 29m
Frontier
Deal found 7/19![Frontier logo]()
$91
This Frontier deal was found by Cheapflights users on 7/19. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Frontier is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 8/138:58 am
ONT
- SFO
Nonstop1h 27m
Frontier
Thu 8/209:00 am
SFO
- ONT
Nonstop1h 29m
Frontier
Deal found 7/19![Frontier logo]()
$92
This Trip.com deal was found by Cheapflights users on 7/15. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Trip.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 8/68:58 am
ONT
- SFO
Nonstop1h 27m
Frontier
Sat 8/89:33 am
SFO
- ONT
Nonstop1h 29m
Frontier
Deal found 7/15![Frontier logo]()
$93
This Frontier deal was found by Cheapflights users on 7/19. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Frontier is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 9/58:48 am
ONT
- SFO
Nonstop1h 27m
Frontier
Sun 9/69:00 am
SFO
- ONT
Nonstop1h 29m
Frontier
Deal found 7/19![Frontier logo]()
$94
This Super.com deal was found by Cheapflights users on 7/17. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Super.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 8/228:48 am
ONT
- SFO
Nonstop1h 27m
Frontier
Mon 8/249:33 am
SFO
- ONT
Nonstop1h 29m
Frontier
Deal found 7/17![Frontier logo]()
$97
This Trip.com deal was found by Cheapflights users on 7/16. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Trip.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 8/88:58 am
ONT
- SFO
Nonstop1h 27m
Frontier
Mon 8/109:33 am
SFO
- ONT
Nonstop1h 29m
Frontier
Deal found 7/16![Frontier logo]()
$98
Best flights from Ontario to USADiscover carefully curated flight deals from Ontario to USA that have cost, travel time, and layovers in mind to ensure you get the best travel experience. Data last updated July 19, 2026.
Discover carefully curated flight deals from Ontario to USA that have cost, travel time, and layovers in mind to ensure you get the best travel experience. Data last updated July 19, 2026.
This Southwest deal was found by Cheapflights users on 7/15. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 8/2910:15 am
ONT
- SFO
2 stops8h 05m
Southwest
Sat 9/56:10 am
SFO
- ONT
1 stop5h 05m
Southwest
Deal found 7/15![Southwest logo]()
$156
This United Airlines deal was found by Cheapflights users on 7/15. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 10/16:07 am
ONT
- SFO
Nonstop1h 27m
United Airlines
Tue 10/67:00 pm
SFO
- ONT
Nonstop1h 31m
United Airlines
Deal found 7/15![United Airlines logo]()
$187
This Alaska Airlines deal was found by Cheapflights users on 7/15. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Alaska Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 8/266:05 pm
ONT
- SEA
1 stop4h 34m
Alaska Airlines
Tue 9/110:41 am
SEA
- ONT
1 stop5h 06m
Alaska Airlines
Deal found 7/15![Alaska Airlines logo]()
$257
This KAYAK deal was found by Cheapflights users on 7/15. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure KAYAK is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 8/266:00 am
ONT
- DEN
1 stop5h 04m
Delta
Wed 8/266:28 pm
DEN
- ONT
1 stop6h 06m
Delta
Deal found 7/15![Delta logo]()
$277
This Cheapflightsfares deal was found by Cheapflights users on 7/19. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Cheapflightsfares is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 9/189:49 pm
ONT
- DEN
1 stop25h 26m
Frontier
Sun 9/207:08 pm
DEN
- ONT
1 stop16h 13m
Frontier
Deal found 7/19![Frontier logo]()
$280
This JetBlue deal was found by Cheapflights users on 7/15. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure JetBlue is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 8/3111:59 pm
ONT
- JFK
Nonstop5h 21m
JetBlue
Wed 9/95:15 pm
JFK
- ONT
Nonstop5h 58m
JetBlue
Deal found 7/15![JetBlue logo]()
$337
This KAYAK deal was found by Cheapflights users on 7/15. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure KAYAK is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 9/3010:25 am
ONT
- DFW
Nonstop3h 07m
American Airlines
Thu 10/110:40 am
DFW
- ONT
Nonstop3h 07m
American Airlines
Deal found 7/15![American Airlines logo]()
$345
This United Airlines deal was found by Cheapflights users on 7/15. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 8/2211:00 am
ONT
- SFO
Nonstop1h 29m
United Airlines
Mon 8/244:40 pm
SFO
- ONT
Nonstop1h 31m
United Airlines
Deal found 7/15![United Airlines logo]()
$188
This Southwest deal was found by Cheapflights users on 7/19. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 8/175:45 pm
ONT
- SFO
1 stop5h 40m
Southwest
Mon 8/242:50 pm
SFO
- ONT
1 stop4h 35m
Southwest
Deal found 7/19![Southwest logo]()
$201
This Southwest deal was found by Cheapflights users on 7/15. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 8/66:30 pm
ONT
- LAS
1 stop3h 55m
Southwest
Sat 8/85:55 am
LAS
- ONT
2 stops6h 25m
Southwest
Deal found 7/15![Southwest logo]()
$242
This Alaska Airlines deal was found by Cheapflights users on 7/16. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Alaska Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 9/237:12 am
ONT
- SEA
1 stop5h 38m
Alaska Airlines
Fri 9/2512:30 pm
SEA
- ONT
1 stop4h 48m
Alaska Airlines
Deal found 7/16![Alaska Airlines logo]()
$267
This United Airlines deal was found by Cheapflights users on 7/17. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 1/711:20 am
ONT
- SFO
Nonstop1h 29m
United Airlines
Sun 1/104:10 pm
SFO
- ONT
Nonstop1h 37m
United Airlines
Deal found 7/17![United Airlines logo]()
$245
This Alaska Airlines deal was found by Cheapflights users on 7/15. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Alaska Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 8/66:02 am
ONT
- HNL
2 stops16h 15m
Multiple Airlines
Thu 8/611:20 pm
HNL
- ONT
1 stop10h 49m
Multiple Airlines
Deal found 7/15![Multiple Airlines logo]()
$565
This Delta deal was found by Cheapflights users on 7/16. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 10/36:00 pm
ONT
- SEA
Nonstop2h 50m
Delta
Mon 10/511:22 am
SEA
- ONT
1 stop5h 13m
Delta
Deal found 7/16![Delta logo]()
$287
This United Airlines deal was found by Cheapflights users on 7/19. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 12/266:00 am
ONT
- SFO
Nonstop1h 33m
United Airlines
Thu 12/319:25 pm
SFO
- ONT
Nonstop1h 23m
United Airlines
Deal found 7/19![United Airlines logo]()
$245
This Southwest deal was found by Cheapflights users on 7/16. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 9/2610:15 am
ONT
- SFO
2 stops8h 05m
Southwest
Sun 9/274:10 pm
SFO
- ONT
1 stop6h 40m
Southwest
Deal found 7/16![Southwest logo]()
$245
This Alaska Airlines deal was found by Cheapflights users on 7/19. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Alaska Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 11/45:12 pm
ONT
- SEA
1 stop4h 18m
Alaska Airlines
Fri 11/2010:54 am
SEA
- ONT
1 stop5h 46m
Alaska Airlines
Deal found 7/19![Alaska Airlines logo]()
$292
This Southwest deal was found by Cheapflights users on 7/15. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 9/184:50 pm
ONT
- SFO
2 stops6h 35m
Southwest
Mon 9/215:10 am
SFO
- ONT
1 stop4h 45m
Southwest
Deal found 7/15![Southwest logo]()
$245
This United Airlines deal was found by Cheapflights users on 7/18. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 8/158:00 am
ONT
- SFO
Nonstop1h 27m
United Airlines
Sat 8/2210:37 am
SFO
- ONT
Nonstop1h 35m
United Airlines
Deal found 7/18![United Airlines logo]()
$247
This Delta deal was found by Cheapflights users on 7/14. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 1/127:00 am
ONT
- LGA
1 stop7h 42m
Delta
Tue 1/196:00 am
LGA
- ONT
1 stop8h 27m
Delta
Deal found 7/14![Delta logo]()
$312
This JetBlue deal was found by Cheapflights users on 7/14. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure JetBlue is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 8/2111:59 pm
ONT
- JFK
Nonstop5h 21m
JetBlue
Mon 8/247:30 pm
JFK
- ONT
Nonstop6h 08m
JetBlue
Deal found 7/14![JetBlue logo]()
$367
This Alaska Airlines deal was found by Cheapflights users on 7/15. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Alaska Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 9/176:14 pm
ONT
- DFW
1 stop17h 05m
Alaska Airlines
Sat 9/195:46 pm
DFW
- ONT
1 stop18h 05m
Alaska Airlines
Deal found 7/15![Alaska Airlines logo]()
$311
This Delta deal was found by Cheapflights users on 7/14. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 1/127:00 am
ONT
- LGA
1 stop7h 42m
Delta
Thu 1/216:00 am
LGA
- ONT
1 stop8h 27m
Delta
Deal found 7/14![Delta logo]()
$312
This Southwest deal was found by Cheapflights users on 7/15. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 8/131:15 pm
ONT
- DEN
1 stop5h 55m
Southwest
Sat 8/1512:55 pm
DEN
- ONT
2 stops6h 25m
Southwest
Deal found 7/15![Southwest logo]()
$262
This United Airlines deal was found by Cheapflights users on 7/14. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 8/256:08 am
ONT
- DFW
1 stop6h 17m
United Airlines
Thu 8/275:45 am
DFW
- ONT
2 stops8h 27m
United Airlines
Deal found 7/14![United Airlines logo]()
$280
This Alaska Airlines deal was found by Cheapflights users on 7/15. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Alaska Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 8/104:18 pm
ONT
- SEA
1 stop5h 03m
Alaska Airlines
Fri 8/213:50 pm
SEA
- ONT
1 stop4h 34m
Alaska Airlines
Deal found 7/15![Alaska Airlines logo]()
$312
This JetBlue deal was found by Cheapflights users on 7/15. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure JetBlue is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 8/1111:59 pm
ONT
- JFK
Nonstop5h 21m
JetBlue
Mon 8/177:30 pm
JFK
- ONT
Nonstop6h 08m
JetBlue
Deal found 7/15![JetBlue logo]()
$387
This Southwest deal was found by Cheapflights users on 7/17. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 10/37:35 am
ONT
- SEA
1 stop4h 35m
Southwest
Mon 10/56:55 am
SEA
- ONT
1 stop5h 05m
Southwest
Deal found 7/17![Southwest logo]()
$267
This KAYAK deal was found by Cheapflights users on 7/15. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure KAYAK is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 9/301:04 pm
ONT
- DFW
1 stop5h 56m
Delta
Thu 10/16:12 pm
DFW
- ONT
1 stop7h 35m
Delta
Deal found 7/15![Delta logo]()
$327
This United Airlines deal was found by Cheapflights users on 7/15. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 8/189:15 am
ONT
- DFW
1 stop6h 36m
United Airlines
Sat 8/225:15 am
DFW
- ONT
2 stops8h 57m
United Airlines
Deal found 7/15![United Airlines logo]()
$280
Last-minute flights from Ontario to USADiscover last-minute flight deals from Ontario to USA. Data last updated July 19, 2026 and is based on user searches.
Discover last-minute flight deals from Ontario to USA. Data last updated July 19, 2026 and is based on user searches.
This Super.com deal was found by Cheapflights users on 7/15. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Super.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 8/58:58 am
ONT
- SFO
Nonstop1h 27m
Frontier
Sat 8/159:33 am
SFO
- ONT
Nonstop1h 29m
Frontier
Deal found 7/15![Frontier logo]()
$101
This Trip.com deal was found by Cheapflights users on 7/15. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Trip.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 8/68:58 am
ONT
- SFO
Nonstop1h 27m
Frontier
Sat 8/89:33 am
SFO
- ONT
Nonstop1h 29m
Frontier
Deal found 7/15![Frontier logo]()
$93
This Super.com deal was found by Cheapflights users on 7/16. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Super.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 8/68:58 am
ONT
- SFO
Nonstop1h 27m
Frontier
Mon 8/109:33 am
SFO
- ONT
Nonstop1h 29m
Frontier
Deal found 7/16![Frontier logo]()
$102
This Super.com deal was found by Cheapflights users on 7/19. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Super.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 8/88:58 am
ONT
- SFO
Nonstop1h 27m
Frontier
Wed 8/1211:15 am
SFO
- ONT
Nonstop1h 33m
Frontier
Deal found 7/19![Frontier logo]()
$89
This Trip.com deal was found by Cheapflights users on 7/16. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Trip.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 8/88:58 am
ONT
- SFO
Nonstop1h 27m
Frontier
Mon 8/109:33 am
SFO
- ONT
Nonstop1h 29m
Frontier
Deal found 7/16![Frontier logo]()
$98
This Cheapflightsfares deal was found by Cheapflights users on 7/17. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Cheapflightsfares is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 8/86:00 am
ONT
- DEN
Nonstop2h 24m
Frontier
Tue 8/188:45 am
DEN
- ONT
Nonstop2h 19m
Frontier
Deal found 7/17![Frontier logo]()
$103
This Frontier deal was found by Cheapflights users on 7/19. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Frontier is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 8/118:58 am
ONT
- SFO
Nonstop1h 27m
Frontier
Tue 8/1812:33 pm
SFO
- ONT
Nonstop1h 30m
Frontier
Deal found 7/19![Frontier logo]()
$88
This Frontier deal was found by Cheapflights users on 7/18. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Frontier is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 8/138:58 am
ONT
- SFO
Nonstop1h 27m
Frontier
Tue 8/1812:33 pm
SFO
- ONT
Nonstop1h 30m
Frontier
Deal found 7/18![Frontier logo]()
$90
This Frontier deal was found by Cheapflights users on 7/19. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Frontier is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 8/138:58 am
ONT
- SFO
Nonstop1h 27m
Frontier
Thu 8/209:00 am
SFO
- ONT
Nonstop1h 29m
Frontier
Deal found 7/19![Frontier logo]()
$92
This Super.com deal was found by Cheapflights users on 7/19. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Super.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 8/158:58 am
ONT
- SFO
Nonstop1h 27m
Frontier
Wed 8/1912:33 pm
SFO
- ONT
Nonstop1h 30m
Frontier
Deal found 7/19![Frontier logo]()
$87
This Super.com deal was found by Cheapflights users on 7/19. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Super.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 8/178:58 am
ONT
- SFO
Nonstop1h 27m
Frontier
Thu 8/209:00 am
SFO
- ONT
Nonstop1h 29m
Frontier
Deal found 7/19![Frontier logo]()
$91
This Super.com deal was found by Cheapflights users on 7/17. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Super.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 8/228:48 am
ONT
- SFO
Nonstop1h 27m
Frontier
Mon 8/249:33 am
SFO
- ONT
Nonstop1h 29m
Frontier
Deal found 7/17![Frontier logo]()
$97
One-way flights from Ontario to USASearch for one-way flight options from Ontario to USA. Find affordable one-way fares based on user searches. Data last updated July 19, 2026.
Search for one-way flight options from Ontario to USA. Find affordable one-way fares based on user searches. Data last updated July 19, 2026.
This iWofly deal was found by Cheapflights users on 7/15. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure iWofly is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 8/193:13 pm
ONT
- SFO
Nonstop1h 27m
Frontier
Deal found 7/15![Frontier logo]()
$28
This Frontier deal was found by Cheapflights users on 7/15. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Frontier is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 9/2811:38 am
ONT
- SFO
Nonstop1h 34m
Frontier
Deal found 7/15![Frontier logo]()
$29
This Super.com deal was found by Cheapflights users on 7/19. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Super.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 9/68:48 am
ONT
- SFO
Nonstop1h 27m
Frontier
Deal found 7/19![Frontier logo]()
$33
This Trip.com deal was found by Cheapflights users on 7/18. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Trip.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 9/1111:38 am
ONT
- SFO
Nonstop1h 34m
Frontier
Deal found 7/18![Frontier logo]()
$36
This Kiwi.com deal was found by Cheapflights users on 7/17. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 9/1411:38 am
ONT
- SFO
Nonstop1h 34m
Frontier
Deal found 7/17![Frontier logo]()
$37
This Super.com deal was found by Cheapflights users on 7/15. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Super.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 10/1911:38 am
ONT
- SFO
Nonstop1h 34m
Frontier
Deal found 7/15![Frontier logo]()
$41
This Super.com deal was found by Cheapflights users on 7/15. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Super.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 11/911:38 am
ONT
- SFO
Nonstop1h 34m
Frontier
Deal found 7/15![Frontier logo]()
$42
This Super.com deal was found by Cheapflights users on 7/19. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Super.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 11/1611:38 am
ONT
- SFO
Nonstop1h 34m
Frontier
Deal found 7/19![Frontier logo]()
$43
This Frontier deal was found by Cheapflights users on 7/19. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Frontier is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 8/298:48 am
ONT
- SFO
Nonstop1h 27m
Frontier
Deal found 7/19![Frontier logo]()
$44
This Super.com deal was found by Cheapflights users on 7/19. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Super.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 9/78:48 am
ONT
- SFO
Nonstop1h 27m
Frontier
Deal found 7/19![Frontier logo]()
$45
This Gotogate deal was found by Cheapflights users on 7/19. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Gotogate is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 8/108:58 am
ONT
- SFO
Nonstop1h 27m
Frontier
Deal found 7/19![Frontier logo]()
$46
This Super.com deal was found by Cheapflights users on 7/17. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Super.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 8/138:58 am
ONT
- SFO
Nonstop1h 27m
Frontier
Deal found 7/17![Frontier logo]()
$47
Find flight deals from Ontario to USA
Keep the following information in mind while searching for Ontario to USA flight deals. Data was last updated July 19, 2026.
Most accurate provider | FlightHub 3 stars |
|---|---|
Most trusted provider | FlightHub 3 stars |
Round-trip from | $84 (Super.com) |
One-way from | $28 (iWofly) |
Popular in | June |
Cheapest in | January |
Average price | $447 |
Good round-trip deal | $173 or less |
Good one-way deal | $90 or less |
Cheapflights Fare Finder
Customize your flight search to find flights from Ontario to USA that fit within your specific budget. Explore options based on user searches and filter the results based on your desired price range. Find flights that match your budget for a cost-effective journey. Over the last 7 days, Cheapflights users made 2,558,603 searches. Data last updated July 19, 2026.
Use the filters below to find and compare flights from Ontario to the United States that are best for you.
Fly from
Fly to
Route
Depart
Return
Cheapest round-trip
OntarioSan Francisco
ONT - SFO
ONTSFO
Ontario
Sat 8/29
10:15 am-6:20 pm
2 stops8h 05m
San Francisco
Sat 9/5
6:10 am-11:15 am
1 stop5h 05m
$156
OntarioSan Francisco
ONT - SFO
ONTSFO
Ontario
Thu 10/1
6:07 am-7:34 am
Nonstop1h 27m
San Francisco
Tue 10/6
7:00 pm-8:31 pm
Nonstop1h 31m
$187
OntarioSan Francisco
ONT - SFO
ONTSFO
Ontario
Sat 8/22
11:00 am-12:29 pm
Nonstop1h 29m
San Francisco
Mon 8/24
4:40 pm-6:11 pm
Nonstop1h 31m
$188
OntarioSan Francisco
ONT - SFO
ONTSFO
Ontario
Mon 8/17
5:45 pm-11:25 pm
1 stop5h 40m
San Francisco
Mon 8/24
2:50 pm-7:25 pm
1 stop4h 35m
$201
OntarioLas Vegas
ONT - LAS
ONTLAS
Ontario
Thu 8/6
6:30 pm-10:25 pm
1 stop3h 55m
Las Vegas Harry Reid Intl
Sat 8/8
5:55 am-12:20 pm
2 stops6h 25m
$242
OntarioSan Francisco
ONT - SFO
ONTSFO
Ontario
Thu 1/7
11:20 am-12:49 pm
Nonstop1h 29m
San Francisco
Sun 1/10
4:10 pm-5:47 pm
Nonstop1h 37m
$245
Quickest round-trip
OntarioSan Francisco
ONT - SFO
ONTSFO
Ontario
Sat 12/26
6:00 am-7:33 am
Nonstop1h 33m
San Francisco
Thu 12/31
9:25 pm-10:48 pm
Nonstop1h 23m
$245
OntarioSan Francisco
ONT - SFO
ONTSFO
Ontario
Sat 9/26
10:15 am-6:20 pm
2 stops8h 05m
San Francisco
Sun 9/27
4:10 pm-10:50 pm
1 stop6h 40m
$245
OntarioSan Francisco
ONT - SFO
ONTSFO
Ontario
Fri 9/18
4:50 pm-11:25 pm
2 stops6h 35m
San Francisco
Mon 9/21
5:10 am-9:55 am
1 stop4h 45m
$245
OntarioSan Francisco
ONT - SFO
ONTSFO
Ontario
Sat 8/15
8:00 am-9:27 am
Nonstop1h 27m
San Francisco
Sat 8/22
10:37 am-12:12 pm
Nonstop1h 35m
$247
Showing 1-10 of 60 resultsSorted by cheapest first
Best time to book a flight from Ontario to USA
Have a flexible travel schedule? Discover the best time to fly to USA from Ontario with our price prediction graph.
ONT-SFO
ONT-DEN
ONT-SEA
ONT-JFK
ONT-HNL
Estimated round-trip price
Rates are based on past data. Find the cheapest month and day to book your flight based on your travel requirements, then search for cheap deals.
Cheapflights Insights
Everything you need to know about your flight from Ontario to the United States
ONT-US0
ONT-SFO
ONT-DEN
ONT-SEA
ONT-JFK
What is the cheapest month to book a flight from Ontario to USA?
Currently, September is the cheapest month in which you can book a flight from Ontario to USA (average of $291). Flying from Ontario to USA in June is currently the most expensive (average of $424). There are several factors that can impact the price of a flight, so comparing airlines, departure airports and flight times can provide users with more options.
What is the cheapest time of day to fly from ONT to US?
Find hourly flight availability from Ontario to USA. Discover flight options and departure times throughout the day, allowing you to choose a departure time that suits your schedule. Data last updated July 19, 2026.
A simple way to save on the total cost of your ticket is to fly from Ontario to USA in the evening. If you’re flexible enough to do this you can expect to save up to 48% on your trip compared to booking a flight in the morning.
How often are flights from Ontario to the United States delayed?
About 14% of weekly flights between Ontario and United States have experienced delays in the past year, with the average delay time being 125 minutes.
What is the most punctual flight time for Ontario to the United States flights?
Historically, flights departing in the morning are less likely to be delayed, whereas flights leaving in the evening tend to experience delays more often.
What day of the week experiences the fewest flight delays on this route?
Sunday tends to have the lowest number of delays on this route, whereas Friday has historically faced a higher average of delays compared to other days of the week.
Which airline has the best punctuality record on Ontario to the United States flights?
Over the last year, Delta have had the lowest number of delays on this route, with just 5% of flights being delayed.
How far ahead should I book a flight from Ontario to USA?
Booking 30 days in advance of your planned departure date is, on average, the best time to get cheap flights from Ontario to USA. The general trend is that the closer you book to the departure date, the more expensive your flight will be.
What is the cheapest day to fly from Ontario to USA?
Use this chart to determine the cheapest time to fly round-trip from Ontario to USA. Price data was last updated on July 11, 2026.
Travelers seeking maximum savings on their Ontario to USA flight should consider departing on Monday at noon when fares are most often at their lowest. Friday afternoons flights should be avoided if possible as fares are typically the most expensive at this time.
Reviews of airlines servicing USA
Get insights into the airlines that provide service to USA. Read reviews, discover amenities, and learn about the overall travel experience offered by airlines. Use this information to make informed decisions when choosing an airline for your flight to USA. Reviews last updated July 19, 2026.
Read reviews from past customers who have flown Southwest,Alaska Airlines, andUnited Airlines from Ontario to the United States. Users can see the overall rating for each airline as well as how each is rated in terms of entertainment options, comfort, food, crew/service, and boarding process.
Comfort
8.0
Overall
8.0
Crew
8.6
Food
7.0
Boarding
8.1
Entertainment
7.5
Reviews
1 / 20
8.0
ExcellentLa Tracimeldamarcos,Jun 2026
LAX - SLC
Comfort
8.0
Overall
8.0
Crew
8.6
Food
7.0
Boarding
8.1
Entertainment
7.5
Reviews
1 / 20
8.0
ExcellentLa Tracimeldamarcos,Jun 2026
LAX - SLC
Comfort
8.0
Overall
8.0
Crew
8.6
Food
7.0
Boarding
8.1
Entertainment
7.5
Reviews
1 / 20
8.0
ExcellentLa Tracimeldamarcos,Jun 2026
LAX - SLC
Comfort
8.0
Overall
8.0
Crew
8.6
Food
7.0
Boarding
8.1
Entertainment
7.5
Reviews
1 / 20
8.0
ExcellentLa Tracimeldamarcos,Jun 2026
LAX - SLC
Comfort
8.0
Overall
8.0
Crew
8.6
Food
7.0
Boarding
8.1
Entertainment
7.5
Reviews
1 / 20
8.0
ExcellentLa Tracimeldamarcos,Jun 2026
LAX - SLC
Comfort
8.0
Overall
8.0
Crew
8.6
Food
7.0
Boarding
8.1
Entertainment
7.5
Reviews
1 / 20
8.0
ExcellentLa Tracimeldamarcos,Jun 2026
LAX - SLC
Related info for your journey
Find useful and relevant information for your journey from Ontario to USA. Access travel guides, tips, and recommendations to enhance your travel experience. Get information about local attractions, weather, transportation options, and more.
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Toggle through the tabs below to find thousands of options on Cheapflights for your next trip.
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Alternative routes for Ontario to USA
See prices for flight routes from nearby airports that may be better suited for you.
Complete your trip
Complete your trip to USA by adding a car rental and/or hotel reservation to your travel itinerary.
Search flights from Ontario to USA by cabin class
Find flights from Ontario to USA, based on your preferred cabin class, be it economy, premium economy, business, or first class.
Ontario and USA flights
Browse other Ontario and USA flight options. Last updated on July 19, 2026.
Popular flight searches
Check out other popular destinations found by fellow travelers in 2026
Ontario to USA flights
Consider these flights traveling from Ontario to USA.
Fly to USA regions
Consider these flights traveling to USA regions.
Top 8 airlines flying from Ontario to USA
Discover the top 8 airlines that operate flights from Ontario to USA. Compare their services, reliability, and customer satisfaction ratings to choose the airline that best suits your travel preferences and needs. Over the last 7 days, Cheapflights users made 2,558,603 searches. Data last updated July 19, 2026.
| Airline | Cheapest | Average | Flexibility | On-time |
|---|---|---|---|---|
| Cheapest$52 | Average$224 | FlexibilityNo cancel fee | On-time62% | |
| Cheapest$78 | Average$371 | FlexibilityNo cancel fee | On-time75% | |
| Cheapest$88 | Average$209 | FlexibilityNo cancel fee | On-time85% | |
| Cheapest$92 | Average$385 | FlexibilityNo cancel fee | On-time69% | |
| Cheapest$102 | Average$396 | FlexibilityNo cancel fee | On-timeN/A | |
| Cheapest$109 | Average$387 | FlexibilityNo cancel fee | On-time63% | |
| Cheapest$153 | Average$352 | FlexibilityNo cancel fee | On-time62% | |
| Cheapest$188 | Average$423 | FlexibilityNo cancel fee | On-time71% |