$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 8/24. Fares are subject to change and may not be available on all flights or dates of travel.
ONT — LAX
Aug 23 — Aug 301
Round-trip
1 adult, Economy
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Find cheap flights from Ontario to USA with Cheapflights
1. Tell us where you want to go
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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 24, 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 24, 2026.
This Frontier deal was found by Cheapflights users on 7/24. 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 8/158:58 am
ONT
- SFO
Nonstop1h 27m
Frontier
Mon 8/179:33 am
SFO
- ONT
Nonstop1h 29m
Frontier
Deal found 7/24![Frontier logo]()
$72
This Super.com deal was found by Cheapflights users on 7/24. 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 9/38:48 am
ONT
- SFO
Nonstop1h 27m
Frontier
Sun 9/69:00 am
SFO
- ONT
Nonstop1h 29m
Frontier
Deal found 7/24![Frontier logo]()
$76
This Frontier deal was found by Cheapflights users on 7/20. 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 9/38:48 am
ONT
- SFO
Nonstop1h 27m
Frontier
Fri 9/1112:31 pm
SFO
- ONT
Nonstop1h 29m
Frontier
Deal found 7/20![Frontier logo]()
$79
This Frontier deal was found by Cheapflights users on 7/23. 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 8/183:13 pm
ONT
- SFO
Nonstop1h 27m
Frontier
Mon 8/319:33 am
SFO
- ONT
Nonstop1h 29m
Frontier
Deal found 7/23![Frontier logo]()
$84
This Super.com deal was found by Cheapflights users on 7/20. 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
Wed 9/212:33 pm
SFO
- ONT
Nonstop1h 30m
Frontier
Deal found 7/20![Frontier logo]()
$86
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.
Tue 8/183:13 pm
ONT
- SFO
Nonstop1h 27m
Frontier
Tue 8/2512:33 pm
SFO
- ONT
Nonstop1h 30m
Frontier
Deal found 7/19![Frontier logo]()
$87
This Frontier deal was found by Cheapflights users on 7/20. 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
Wed 8/1211:15 am
SFO
- ONT
Nonstop1h 33m
Frontier
Deal found 7/20![Frontier logo]()
$88
This Super.com deal was found by Cheapflights users on 7/20. 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
Sat 8/229:33 am
SFO
- ONT
Nonstop1h 29m
Frontier
Deal found 7/20![Frontier logo]()
$89
This Frontier deal was found by Cheapflights users on 7/20. 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 8/108:58 am
ONT
- SFO
Nonstop1h 27m
Frontier
Tue 8/1111:15 am
SFO
- ONT
Nonstop1h 33m
Frontier
Deal found 7/20![Frontier logo]()
$90
This Super.com deal was found by Cheapflights users on 7/20. 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 8/108:58 am
ONT
- SFO
Nonstop1h 27m
Frontier
Thu 8/209:00 am
SFO
- ONT
Nonstop1h 29m
Frontier
Deal found 7/20![Frontier logo]()
$91
This Expedia deal was found by Cheapflights users on 7/20. 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 Expedia 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
Mon 8/179:33 am
SFO
- ONT
Nonstop1h 29m
Frontier
Deal found 7/20![Frontier logo]()
$92
This Cheapflightsfares deal was found by Cheapflights users on 7/23. 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.
Thu 10/296:15 am
ONT
- DEN
Nonstop2h 26m
Frontier
Mon 11/29:15 am
DEN
- ONT
Nonstop2h 28m
Frontier
Deal found 7/23![Frontier logo]()
$106
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 24, 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 24, 2026.
This Southwest deal was found by Cheapflights users on 7/23. 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.
Wed 10/286:10 am
ONT
- SFO
2 stops9h 00m
Southwest
Sat 10/318:10 am
SFO
- ONT
1 stop4h 35m
Southwest
Deal found 7/23![Southwest logo]()
$162
This United Airlines deal was found by Cheapflights users on 7/23. 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 9/86:08 am
ONT
- SFO
Nonstop1h 27m
United Airlines
Tue 9/86:30 pm
SFO
- ONT
Nonstop1h 31m
United Airlines
Deal found 7/23![United Airlines logo]()
$207
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.
Sat 9/197:12 am
ONT
- SEA
1 stop4h 46m
Alaska Airlines
Wed 9/239:55 am
SEA
- ONT
1 stop6h 15m
Alaska Airlines
Deal found 7/19![Alaska Airlines logo]()
$237
This Delta deal was found by Cheapflights users on 7/20. 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 9/51:06 pm
ONT
- DEN
1 stop5h 55m
Delta
Sun 9/66:28 pm
DEN
- ONT
1 stop4h 55m
Delta
Deal found 7/20![Delta logo]()
$278
This Southwest deal was found by Cheapflights users on 7/23. 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 10m
Southwest
Mon 9/285:10 am
SFO
- ONT
1 stop6h 15m
Southwest
Deal found 7/23![Southwest logo]()
$162
This JetBlue 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 JetBlue is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 8/3011:59 pm
ONT
- JFK
Nonstop5h 21m
JetBlue
Sat 9/56:50 pm
JFK
- ONT
Nonstop6h 09m
JetBlue
Deal found 7/19![JetBlue logo]()
$337
This Southwest deal was found by Cheapflights users on 7/23. 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.
Tue 9/291:50 pm
ONT
- DEN
Nonstop2h 15m
Southwest
Sat 10/35:45 am
DEN
- ONT
2 stops6h 25m
Southwest
Deal found 7/23![Southwest logo]()
$172
This KAYAK 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 KAYAK is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 8/252:27 pm
ONT
- DFW
Nonstop3h 16m
American Airlines
Thu 8/279:59 pm
DFW
- ONT
Nonstop3h 00m
American Airlines
Deal found 7/19![American Airlines logo]()
$381
This United Airlines deal was found by Cheapflights users on 7/21. 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.
Wed 9/166:08 am
ONT
- SFO
Nonstop1h 27m
United Airlines
Wed 9/164:45 pm
SFO
- ONT
Nonstop1h 31m
United Airlines
Deal found 7/21![United Airlines logo]()
$207
This Southwest deal was found by Cheapflights users on 7/22. 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.
Wed 8/1912:30 pm
ONT
- DEN
1 stop6h 20m
Southwest
Wed 8/262:00 pm
DEN
- ONT
1 stop4h 35m
Southwest
Deal found 7/22![Southwest logo]()
$187
This United Airlines deal was found by Cheapflights users on 7/23. 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 9/241:52 pm
ONT
- SFO
Nonstop1h 29m
United Airlines
Sat 9/264:15 pm
SFO
- ONT
Nonstop1h 31m
United Airlines
Deal found 7/23![United Airlines logo]()
$207
This United Airlines deal was found by Cheapflights users on 7/21. 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 9/511:00 am
ONT
- SFO
Nonstop1h 29m
United Airlines
Mon 9/710:37 am
SFO
- ONT
Nonstop1h 35m
United Airlines
Deal found 7/21![United Airlines logo]()
$207
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.
Wed 9/94:45 pm
ONT
- SFO
1 stop4h 35m
Southwest
Sat 9/126:10 am
SFO
- ONT
1 stop5h 05m
Southwest
Deal found 7/19![Southwest logo]()
$197
This Alaska Airlines deal was found by Cheapflights users on 7/23. 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 8/139:11 am
ONT
- HNL
Nonstop5h 58m
Multiple Airlines
Mon 8/175:30 pm
HNL
- ONT
2 stops27h 23m
Multiple Airlines
Deal found 7/23![Multiple Airlines logo]()
$548
This Delta deal was found by Cheapflights users on 7/21. 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 8/186:01 pm
ONT
- SEA
Nonstop2h 49m
Delta
Tue 8/258:22 am
SEA
- ONT
Nonstop2h 54m
Delta
Deal found 7/21![Delta logo]()
$292
This Alaska Airlines deal was found by Cheapflights users on 7/22. 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
Sun 9/133:51 pm
SEA
- ONT
1 stop4h 33m
Alaska Airlines
Deal found 7/22![Alaska Airlines logo]()
$297
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.
Thu 10/15:15 pm
ONT
- SFO
2 stops7h 20m
Southwest
Mon 10/57:25 pm
SFO
- ONT
1 stop4h 30m
Southwest
Deal found 7/19![Southwest logo]()
$206
This United Airlines deal was found by Cheapflights users on 7/21. 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 9/125:00 am
ONT
- DEN
Nonstop2h 21m
United Airlines
Sat 9/197:30 pm
DEN
- ONT
Nonstop2h 23m
United Airlines
Deal found 7/21![United Airlines logo]()
$237
This Alaska Airlines deal was found by Cheapflights users on 7/24. 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 9/247:12 am
ONT
- SEA
1 stop5h 38m
Alaska Airlines
Sun 9/2712:30 pm
SEA
- ONT
1 stop4h 48m
Alaska Airlines
Deal found 7/24![Alaska Airlines logo]()
$307
This United Airlines deal was found by Cheapflights users on 7/23. 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 8/205:00 am
ONT
- DEN
Nonstop2h 21m
United Airlines
Thu 8/277:30 pm
DEN
- ONT
Nonstop2h 23m
United Airlines
Deal found 7/23![United Airlines logo]()
$237
This JetBlue deal was found by Cheapflights users on 7/23. 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 8/2411:59 pm
ONT
- JFK
Nonstop5h 21m
JetBlue
Wed 8/267:29 pm
JFK
- ONT
Nonstop6h 08m
JetBlue
Deal found 7/23![JetBlue logo]()
$347
This Delta deal was found by Cheapflights users on 7/23. 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.
Fri 8/2112:00 pm
ONT
- LGA
1 stop8h 24m
Delta
Tue 8/256:00 am
LGA
- ONT
1 stop7h 42m
Delta
Deal found 7/23![Delta logo]()
$342
This Southwest deal was found by Cheapflights users on 7/21. 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.
Wed 8/123:00 pm
ONT
- LAS
1 stop4h 45m
Southwest
Thu 8/133:20 pm
LAS
- ONT
1 stop4h 35m
Southwest
Deal found 7/21![Southwest logo]()
$237
This JetBlue deal was found by Cheapflights users on 7/22. 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.
Sat 9/1210:39 pm
ONT
- JFK
Nonstop5h 21m
JetBlue
Sat 9/195:59 pm
JFK
- ONT
Nonstop5h 58m
JetBlue
Deal found 7/22![JetBlue logo]()
$358
This United Airlines deal was found by Cheapflights users on 7/20. 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.
Wed 9/239:01 am
ONT
- SFO
Nonstop1h 29m
United Airlines
Mon 9/287:00 pm
SFO
- ONT
Nonstop1h 31m
United Airlines
Deal found 7/20![United Airlines logo]()
$249
This Southwest deal was found by Cheapflights users on 7/23. 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.
Wed 9/99:10 am
ONT
- LAS
1 stop3h 25m
Southwest
Sat 9/125:55 am
LAS
- ONT
2 stops6h 25m
Southwest
Deal found 7/23![Southwest logo]()
$240
This Delta deal was found by Cheapflights users on 7/20. 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.
Fri 10/210:00 pm
ONT
- DFW
1 stop10h 12m
Delta
Mon 10/51:44 pm
DFW
- ONT
2 stops12h 03m
Delta
Deal found 7/20![Delta logo]()
$359
This Alaska Airlines deal was found by Cheapflights users on 7/24. 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.
Sun 9/274:27 pm
ONT
- DEN
2 stops18h 53m
Alaska Airlines
Mon 9/287:30 pm
DEN
- ONT
1 stop16h 46m
Alaska Airlines
Deal found 7/24![Alaska Airlines logo]()
$360
This JetBlue deal was found by Cheapflights users on 7/20. 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 8/1011:59 pm
ONT
- JFK
Nonstop5h 21m
JetBlue
Wed 8/197:29 pm
JFK
- ONT
Nonstop6h 08m
JetBlue
Deal found 7/20![JetBlue logo]()
$362
This Southwest deal was found by Cheapflights users on 7/21. 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 8/295:50 am
ONT
- LAS
2 stops6h 20m
Southwest
Mon 8/315:15 pm
LAS
- ONT
1 stop4h 55m
Southwest
Deal found 7/21![Southwest logo]()
$242
Last-minute flights from Ontario to USADiscover last-minute flight deals from Ontario to USA. Data last updated July 24, 2026 and is based on user searches.
Discover last-minute flight deals from Ontario to USA. Data last updated July 24, 2026 and is based on user searches.
This Frontier deal was found by Cheapflights users on 7/20. 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 8/108:58 am
ONT
- SFO
Nonstop1h 27m
Frontier
Tue 8/1111:15 am
SFO
- ONT
Nonstop1h 33m
Frontier
Deal found 7/20![Frontier logo]()
$90
This Super.com deal was found by Cheapflights users on 7/20. 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 8/108:58 am
ONT
- SFO
Nonstop1h 27m
Frontier
Thu 8/209:00 am
SFO
- ONT
Nonstop1h 29m
Frontier
Deal found 7/20![Frontier logo]()
$91
This Frontier deal was found by Cheapflights users on 7/20. 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
Wed 8/1211:15 am
SFO
- ONT
Nonstop1h 33m
Frontier
Deal found 7/20![Frontier logo]()
$88
This Expedia deal was found by Cheapflights users on 7/20. 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 Expedia 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
Mon 8/179:33 am
SFO
- ONT
Nonstop1h 29m
Frontier
Deal found 7/20![Frontier logo]()
$92
This Frontier deal was found by Cheapflights users on 7/24. 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 8/158:58 am
ONT
- SFO
Nonstop1h 27m
Frontier
Mon 8/179:33 am
SFO
- ONT
Nonstop1h 29m
Frontier
Deal found 7/24![Frontier logo]()
$72
This Super.com deal was found by Cheapflights users on 7/20. 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
Sat 8/229:33 am
SFO
- ONT
Nonstop1h 29m
Frontier
Deal found 7/20![Frontier logo]()
$89
This Frontier deal was found by Cheapflights users on 7/23. 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 8/183:13 pm
ONT
- SFO
Nonstop1h 27m
Frontier
Mon 8/319:33 am
SFO
- ONT
Nonstop1h 29m
Frontier
Deal found 7/23![Frontier logo]()
$84
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.
Tue 8/183:13 pm
ONT
- SFO
Nonstop1h 27m
Frontier
Tue 8/2512:33 pm
SFO
- ONT
Nonstop1h 30m
Frontier
Deal found 7/19![Frontier logo]()
$87
This Super.com deal was found by Cheapflights users on 7/20. 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
Wed 9/212:33 pm
SFO
- ONT
Nonstop1h 30m
Frontier
Deal found 7/20![Frontier logo]()
$86
This Trip.com deal was found by Cheapflights users on 7/20. 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.
Tue 8/253:13 pm
ONT
- SFO
Nonstop1h 27m
Frontier
Mon 8/319:33 am
SFO
- ONT
Nonstop1h 29m
Frontier
Deal found 7/20![Frontier logo]()
$94
This Frontier deal was found by Cheapflights users on 7/22. 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 8/278:48 am
ONT
- SFO
Nonstop1h 27m
Frontier
Mon 8/319:33 am
SFO
- ONT
Nonstop1h 29m
Frontier
Deal found 7/22![Frontier logo]()
$102
This Frontier deal was found by Cheapflights users on 7/22. 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
Mon 8/319:33 am
SFO
- ONT
Nonstop1h 29m
Frontier
Deal found 7/22![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 24, 2026.
Search for one-way flight options from Ontario to USA. Find affordable one-way fares based on user searches. Data last updated July 24, 2026.
This Booking.com deal was found by Cheapflights users on 7/22. 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 Booking.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 8/248:48 am
ONT
- SFO
Nonstop1h 27m
Frontier
Deal found 7/22![Frontier logo]()
$28
This Trip.com deal was found by Cheapflights users on 7/22. 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 11/1211:38 am
ONT
- SFO
Nonstop1h 34m
Frontier
Deal found 7/22![Frontier logo]()
$29
This Trip.com deal was found by Cheapflights users on 7/24. 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.
Mon 9/1412:07 pm
ONT
- SFO
Nonstop1h 36m
Frontier
Deal found 7/24![Frontier logo]()
$31
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 Super.com deal was found by Cheapflights users on 7/23. 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.
Fri 9/1111:38 am
ONT
- SFO
Nonstop1h 34m
Frontier
Deal found 7/23![Frontier logo]()
$38
This Super.com deal was found by Cheapflights users on 7/21. 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 7/21![Frontier logo]()
$43
This Super.com deal was found by Cheapflights users on 7/20. 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 8/193:13 pm
ONT
- SFO
Nonstop1h 27m
Frontier
Deal found 7/20![Frontier logo]()
$44
This Frontier deal was found by Cheapflights users on 7/20. 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 8/253:13 pm
ONT
- SFO
Nonstop1h 27m
Frontier
Deal found 7/20![Frontier logo]()
$45
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.
Mon 8/178:58 am
ONT
- SFO
Nonstop1h 27m
Frontier
Deal found 7/19![Frontier logo]()
$46
This Frontier deal was found by Cheapflights users on 7/20. 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 11/1611:38 am
ONT
- SFO
Nonstop1h 34m
Frontier
Deal found 7/20![Frontier logo]()
$47
This Kiwi.com deal was found by Cheapflights users on 7/22. 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.
Tue 8/183:13 pm
ONT
- LAS
1 stop21h 52m
Frontier
Deal found 7/22![Frontier logo]()
$52
This Super.com deal was found by Cheapflights users on 7/22. 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.
Fri 10/3011:38 am
ONT
- SFO
Nonstop1h 34m
Frontier
Deal found 7/22![Frontier logo]()
$52
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 24, 2026.
Most accurate provider | FlightHub 3 stars |
|---|---|
Most trusted provider | FlightHub 3 stars |
Round-trip from | $72 (Frontier) |
One-way from | $28 (Booking.com) |
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 24, 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
Wed 10/28
6:10 am-3:10 pm
2 stops9h 00m
San Francisco
Sat 10/31
8:10 am-12:45 pm
1 stop4h 35m
$162
OntarioSan Francisco
ONT - SFO
ONTSFO
Ontario
Sat 9/26
10:15 am-6:25 pm
2 stops8h 10m
San Francisco
Mon 9/28
5:10 am-11:25 am
1 stop6h 15m
$162
OntarioDenver
ONT - DEN
ONTDEN
Ontario
Tue 9/29
1:50 pm-5:05 pm
Nonstop2h 15m
Denver Intl
Sat 10/3
5:45 am-11:10 am
2 stops6h 25m
$172
OntarioDenver
ONT - DEN
ONTDEN
Ontario
Wed 8/19
12:30 pm-7:50 pm
1 stop6h 20m
Denver Intl
Wed 8/26
2:00 pm-5:35 pm
1 stop4h 35m
$187
OntarioSan Francisco
ONT - SFO
ONTSFO
Ontario
Wed 9/9
4:45 pm-9:20 pm
1 stop4h 35m
San Francisco
Sat 9/12
6:10 am-11:15 am
1 stop5h 05m
$197
OntarioSan Francisco
ONT - SFO
ONTSFO
Ontario
Thu 10/1
5:15 pm-12:35 am
2 stops7h 20m
San Francisco
Mon 10/5
7:25 pm-11:55 pm
1 stop4h 30m
$206
Quickest round-trip
OntarioSan Francisco
ONT - SFO
ONTSFO
Ontario
Tue 9/8
6:08 am-7:35 am
Nonstop1h 27m
San Francisco
Tue 9/8
6:30 pm-8:01 pm
Nonstop1h 31m
$207
OntarioSan Francisco
ONT - SFO
ONTSFO
Ontario
Wed 9/16
6:08 am-7:35 am
Nonstop1h 27m
San Francisco
Wed 9/16
4:45 pm-6:16 pm
Nonstop1h 31m
$207
OntarioSan Francisco
ONT - SFO
ONTSFO
Ontario
Thu 9/24
1:52 pm-3:21 pm
Nonstop1h 29m
San Francisco
Sat 9/26
4:15 pm-5:46 pm
Nonstop1h 31m
$207
OntarioSan Francisco
ONT - SFO
ONTSFO
Ontario
Sat 9/5
11:00 am-12:29 pm
Nonstop1h 29m
San Francisco
Mon 9/7
10:37 am-12:12 pm
Nonstop1h 35m
$207
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-LAS
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 24, 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 51% 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 124 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 18, 2026.
Travelers seeking maximum savings on their Ontario to USA flight should consider departing on Thursday evenings 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 24, 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.
Overall
8.0
Entertainment
7.5
Comfort
8.0
Food
7.0
Crew
8.6
Boarding
8.1
Reviews
1 / 20
8.0
ExcellentLa Tracimeldamarcos,Jun 2026
LAX - SLC
Overall
8.0
Entertainment
7.5
Comfort
8.0
Food
7.0
Crew
8.6
Boarding
8.1
Reviews
1 / 20
8.0
ExcellentLa Tracimeldamarcos,Jun 2026
LAX - SLC
Overall
8.0
Entertainment
7.5
Comfort
8.0
Food
7.0
Crew
8.6
Boarding
8.1
Reviews
1 / 20
8.0
ExcellentLa Tracimeldamarcos,Jun 2026
LAX - SLC
Overall
8.0
Entertainment
7.5
Comfort
8.0
Food
7.0
Crew
8.6
Boarding
8.1
Reviews
1 / 20
8.0
ExcellentLa Tracimeldamarcos,Jun 2026
LAX - SLC
Overall
8.0
Entertainment
7.5
Comfort
8.0
Food
7.0
Crew
8.6
Boarding
8.1
Reviews
1 / 20
8.0
ExcellentLa Tracimeldamarcos,Jun 2026
LAX - SLC
Overall
8.0
Entertainment
7.5
Comfort
8.0
Food
7.0
Crew
8.6
Boarding
8.1
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 24, 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 7 airlines flying from Ontario to USA
Discover the top 7 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 24, 2026.
| Airline | Cheapest | Average | Flexibility | On-time |
|---|---|---|---|---|
| Cheapest$52 | Average$228 | FlexibilityNo cancel fee | On-time62% | |
| Cheapest$78 | Average$389 | FlexibilityNo cancel fee | On-time75% | |
| Cheapest$92 | Average$377 | FlexibilityNo cancel fee | On-time69% | |
| Cheapest$113 | Average$399 | FlexibilityNo cancel fee | On-time63% | |
| Cheapest$128 | Average$413 | FlexibilityNo cancel fee | On-timeN/A | |
| Cheapest$148 | Average$358 | FlexibilityNo cancel fee | On-time62% | |
| Cheapest$193 | Average$412 | FlexibilityNo cancel fee | On-time71% |