$26+ 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 8/18. Fares are subject to change and may not be available on all flights or dates of travel.
ONT — LAX
jun 20 — jun 271
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
Enter your travel information like dates, passengers, trip type (one-way or round trip), and preferred cabin class then click “Find deals”2. Select your favorite providers
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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 maio 21, 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 maio 21, 2026.
This Kiwi.com deal was found by Cheapflights users on 5/16. 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
qui 8/611:43 am
ONT
- LAS
Nonstop1h 10m
Frontier
seg 8/106:46 pm
LAS
- ONT
Nonstop1h 07m
Frontier
Deal found 5/16![Frontier logo]()
$74
This Frontier deal was found by Cheapflights users on 5/19. 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.
ter 9/159:49 pm
ONT
- LAS
Nonstop1h 09m
Frontier
seg 9/213:00 pm
LAS
- ONT
Nonstop1h 10m
Frontier
Deal found 5/19![Frontier logo]()
$75
This Frontier deal was found by Cheapflights users on 5/20. 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.
seg 9/1411:16 am
ONT
- LAS
Nonstop1h 11m
Frontier
ter 9/157:45 pm
LAS
- ONT
Nonstop1h 09m
Frontier
Deal found 5/20![Frontier logo]()
$76
This Trip.com deal was found by Cheapflights users on 5/18. 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.
qui 8/611:43 am
ONT
- LAS
Nonstop1h 10m
Frontier
sáb 8/86:46 pm
LAS
- ONT
Nonstop1h 07m
Frontier
Deal found 5/18![Frontier logo]()
$78
This Super.com deal was found by Cheapflights users on 5/19. 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.
qui 8/273:34 pm
ONT
- LAS
Nonstop1h 12m
Frontier
seg 8/311:56 pm
LAS
- ONT
Nonstop1h 13m
Frontier
Deal found 5/19![Frontier logo]()
$84
This Frontier deal was found by Cheapflights users on 5/21. 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 Frontier is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
sáb 9/262:58 pm
ONT
- LAS
Nonstop1h 10m
Frontier
ter 9/297:45 pm
LAS
- ONT
Nonstop1h 09m
Frontier
Deal found 5/21![Frontier logo]()
$87
This Frontier deal was found by Cheapflights users on 5/19. 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.
qui 9/2411:16 am
ONT
- LAS
Nonstop1h 11m
Frontier
qui 9/243:00 pm
LAS
- ONT
Nonstop1h 10m
Frontier
Deal found 5/19![Frontier logo]()
$89
This CheapOair deal was found by Cheapflights users on 5/21. 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 CheapOair is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
qua 9/302:58 pm
ONT
- LAS
Nonstop1h 10m
Frontier
qua 10/73:00 pm
LAS
- ONT
Nonstop1h 10m
Frontier
Deal found 5/21![Frontier logo]()
$90
This Super.com deal was found by Cheapflights users on 5/18. 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 Super.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
ter 6/163:34 pm
ONT
- LAS
Nonstop1h 12m
Frontier
sex 6/191:55 pm
LAS
- ONT
Nonstop1h 13m
Frontier
Deal found 5/18![Frontier logo]()
$92
This Frontier deal was found by Cheapflights users on 5/20. 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.
sáb 8/111:43 am
ONT
- LAS
Nonstop1h 10m
Frontier
qua 8/51:56 pm
LAS
- ONT
Nonstop1h 11m
Frontier
Deal found 5/20![Frontier logo]()
$93
This Frontier deal was found by Cheapflights users on 5/20. 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.
qui 9/1711:16 am
ONT
- LAS
Nonstop1h 11m
Frontier
seg 9/217:45 pm
LAS
- ONT
Nonstop1h 09m
Frontier
Deal found 5/20![Frontier logo]()
$94
This FlightHub deal was found by Cheapflights users on 5/18. 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 FlightHub is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
ter 6/91:33 pm
ONT
- LAS
Nonstop1h 11m
Frontier
sex 6/126:43 pm
LAS
- ONT
Nonstop1h 08m
Frontier
Deal found 5/18![Frontier logo]()
$95
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 maio 21, 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 maio 21, 2026.
This Southwest deal was found by Cheapflights users on 5/20. 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 Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
sáb 8/155:50 am
ONT
- DEN
2 stops5h 40m
Southwest
ter 8/188:40 pm
DEN
- ONT
Nonstop2h 20m
Southwest
Deal found 5/20![Southwest logo]()
$172
This Delta deal was found by Cheapflights users on 5/20. 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.
seg 8/1012:55 pm
ONT
- DEN
1 stop6h 06m
Delta
ter 8/116:18 pm
DEN
- ONT
1 stop6h 16m
Delta
Deal found 5/20![Delta logo]()
$197
This United Airlines deal was found by Cheapflights users on 5/20. 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.
ter 6/236:00 am
ONT
- SFO
Nonstop1h 25m
United Airlines
ter 6/2310:40 am
SFO
- ONT
Nonstop1h 32m
United Airlines
Deal found 5/20![United Airlines logo]()
$202
This Alaska Airlines deal was found by Cheapflights users on 5/20. 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 Alaska Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
sex 6/129:20 pm
ONT
- SEA
Nonstop2h 39m
Alaska Airlines
dom 6/148:30 am
SEA
- ONT
Nonstop2h 41m
Alaska Airlines
Deal found 5/20![Alaska Airlines logo]()
$327
This JetBlue deal was found by Cheapflights users on 5/17. 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 JetBlue is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
ter 7/711:50 pm
ONT
- JFK
Nonstop5h 21m
JetBlue
seg 7/137:30 pm
JFK
- ONT
Nonstop6h 05m
JetBlue
Deal found 5/17![JetBlue logo]()
$357
This Southwest deal was found by Cheapflights users on 5/20. 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 Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
qua 8/261:10 pm
ONT
- SFO
2 stops5h 55m
Southwest
sáb 8/295:00 am
SFO
- ONT
1 stop3h 45m
Southwest
Deal found 5/20![Southwest logo]()
$182
This Delta deal was found by Cheapflights users on 5/18. 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 Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
ter 7/71:00 pm
ONT
- DEN
1 stop6h 01m
Delta
ter 7/145:40 am
DEN
- ONT
1 stop4h 07m
Delta
Deal found 5/18![Delta logo]()
$197
This Southwest deal was found by Cheapflights users on 5/20. 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 Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
ter 8/181:15 pm
ONT
- DEN
1 stop5h 35m
Southwest
qui 8/209:45 am
DEN
- ONT
2 stops6h 20m
Southwest
Deal found 5/20![Southwest logo]()
$182
This United Airlines deal was found by Cheapflights users on 5/20. 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.
ter 9/89:01 am
ONT
- SFO
Nonstop1h 29m
United Airlines
qua 9/94:45 pm
SFO
- ONT
Nonstop1h 31m
United Airlines
Deal found 5/20![United Airlines logo]()
$207
This KAYAK deal was found by Cheapflights users on 5/16. 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 KAYAK is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
dom 5/317:12 pm
ONT
- JFK
1 stop7h 32m
American Airlines
qui 6/43:30 pm
JFK
- ONT
1 stop10h 06m
American Airlines
Deal found 5/16![American Airlines logo]()
$414
This Delta deal was found by Cheapflights users on 5/20. 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.
qui 8/612:55 pm
ONT
- DEN
1 stop6h 06m
Delta
sáb 8/86:49 am
DEN
- ONT
1 stop6h 16m
Delta
Deal found 5/20![Delta logo]()
$197
This United Airlines deal was found by Cheapflights users on 5/19. 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.
ter 6/161:50 pm
ONT
- SFO
Nonstop1h 25m
United Airlines
qua 6/1710:40 am
SFO
- ONT
Nonstop1h 32m
United Airlines
Deal found 5/19![United Airlines logo]()
$207
This Southwest deal was found by Cheapflights users on 5/20. 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 Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
qui 9/106:10 am
ONT
- LAS
2 stops5h 15m
Southwest
seg 9/146:20 pm
LAS
- ONT
Nonstop1h 05m
Southwest
Deal found 5/20![Southwest logo]()
$192
This Delta deal was found by Cheapflights users on 5/17. 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 Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
qua 8/196:00 am
ONT
- DEN
1 stop5h 04m
Delta
sáb 8/226:18 pm
DEN
- ONT
1 stop4h 47m
Delta
Deal found 5/17![Delta logo]()
$197
This Alaska Airlines deal was found by Cheapflights users on 5/20. 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 Alaska Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
seg 8/102:05 pm
ONT
- HNL
1 stop12h 23m
Multiple Airlines
sex 8/1411:20 pm
HNL
- ONT
1 stop10h 49m
Multiple Airlines
Deal found 5/20![Multiple Airlines logo]()
$501
This Delta deal was found by Cheapflights users on 5/18. 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 Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
qua 7/81:00 pm
ONT
- DEN
1 stop6h 01m
Delta
ter 7/147:09 pm
DEN
- ONT
1 stop5h 39m
Delta
Deal found 5/18![Delta logo]()
$197
This United Airlines deal was found by Cheapflights users on 5/19. 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.
dom 6/216:00 am
ONT
- LAS
1 stop4h 24m
United Airlines
ter 6/236:20 pm
LAS
- ONT
1 stop4h 17m
United Airlines
Deal found 5/19![United Airlines logo]()
$223
This Southwest deal was found by Cheapflights users on 5/20. 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 Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
seg 8/36:30 am
ONT
- LAS
2 stops5h 05m
Southwest
qua 8/127:50 pm
LAS
- ONT
Nonstop1h 05m
Southwest
Deal found 5/20![Southwest logo]()
$218
This United Airlines deal was found by Cheapflights users on 5/17. 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.
qua 10/79:39 am
ONT
- SFO
Nonstop1h 29m
United Airlines
qui 10/810:37 am
SFO
- ONT
Nonstop1h 35m
United Airlines
Deal found 5/17![United Airlines logo]()
$227
This Alaska Airlines deal was found by Cheapflights users on 5/17. 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 Alaska Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
qua 11/115:52 pm
ONT
- JFK
1 stop10h 33m
Alaska Airlines
seg 11/167:00 am
JFK
- ONT
1 stop11h 15m
Alaska Airlines
Deal found 5/17![Alaska Airlines logo]()
$342
This Southwest deal was found by Cheapflights users on 5/16. 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.
ter 6/97:20 pm
ONT
- SFO
1 stop4h 05m
Southwest
ter 6/166:00 am
SFO
- ONT
2 stops8h 05m
Southwest
Deal found 5/16![Southwest logo]()
$237
This JetBlue deal was found by Cheapflights users on 5/17. 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 JetBlue is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
ter 7/711:50 pm
ONT
- JFK
Nonstop5h 21m
JetBlue
ter 7/147:30 pm
JFK
- ONT
Nonstop6h 05m
JetBlue
Deal found 5/17![JetBlue logo]()
$357
This United Airlines deal was found by Cheapflights users on 5/20. 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.
sáb 10/106:05 am
ONT
- SFO
Nonstop1h 27m
United Airlines
sáb 10/179:25 pm
SFO
- ONT
Nonstop1h 34m
United Airlines
Deal found 5/20![United Airlines logo]()
$247
This Southwest deal was found by Cheapflights users on 5/20. 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 Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
sex 8/76:10 am
ONT
- LAS
2 stops5h 15m
Southwest
seg 8/106:20 pm
LAS
- ONT
Nonstop1h 05m
Southwest
Deal found 5/20![Southwest logo]()
$238
This Alaska Airlines deal was found by Cheapflights users on 5/19. 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.
sex 10/97:23 am
ONT
- JFK
1 stop9h 02m
Alaska Airlines
qua 10/144:23 pm
JFK
- ONT
1 stop10h 19m
Alaska Airlines
Deal found 5/19![Alaska Airlines logo]()
$361
This Delta deal was found by Cheapflights users on 5/16. 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.
sáb 9/266:00 am
ONT
- ORD
2 stops8h 48m
Delta
ter 9/298:55 am
ORD
- ONT
2 stops11h 06m
Delta
Deal found 5/16![Delta logo]()
$283
This JetBlue deal was found by Cheapflights users on 5/17. 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 JetBlue is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
seg 7/611:50 pm
ONT
- JFK
Nonstop5h 21m
JetBlue
ter 7/147:30 pm
JFK
- ONT
Nonstop6h 05m
JetBlue
Deal found 5/17![JetBlue logo]()
$382
This Southwest deal was found by Cheapflights users on 5/17. 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.
qui 8/62:40 pm
ONT
- LAS
1 stop4h 40m
Southwest
dom 8/97:00 am
LAS
- ONT
1 stop3h 40m
Southwest
Deal found 5/17![Southwest logo]()
$243
This Alaska Airlines deal was found by Cheapflights users on 5/20. 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 Alaska Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
qui 9/1010:47 am
ONT
- EWR
1 stop9h 42m
Alaska Airlines
seg 9/147:20 am
EWR
- ONT
1 stop9h 56m
Alaska Airlines
Deal found 5/20![Alaska Airlines logo]()
$369
This KAYAK deal was found by Cheapflights users on 5/20. 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 KAYAK is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
seg 6/157:13 pm
ONT
- JFK
1 stop7h 31m
American Airlines
qui 6/183:30 pm
JFK
- ONT
1 stop10h 06m
American Airlines
Deal found 5/20![American Airlines logo]()
$452
Last-minute flights from Ontario to USADiscover last-minute flight deals from Ontario to USA. Data last updated maio 21, 2026 and is based on user searches.
Discover last-minute flight deals from Ontario to USA. Data last updated maio 21, 2026 and is based on user searches.
This Frontier deal was found by Cheapflights users on 5/18. 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.
seg 6/811:51 am
ONT
- LAS
Nonstop1h 11m
Frontier
ter 6/96:43 pm
LAS
- ONT
Nonstop1h 08m
Frontier
Deal found 5/18![Frontier logo]()
$107
This FlightHub deal was found by Cheapflights users on 5/18. 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 FlightHub is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
ter 6/91:33 pm
ONT
- LAS
Nonstop1h 11m
Frontier
sex 6/126:43 pm
LAS
- ONT
Nonstop1h 08m
Frontier
Deal found 5/18![Frontier logo]()
$95
This Super.com deal was found by Cheapflights users on 5/17. 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.
ter 6/98:36 pm
ONT
- SFO
Nonstop1h 37m
Frontier
dom 6/219:41 am
SFO
- ONT
Nonstop1h 32m
Frontier
Deal found 5/17![Frontier logo]()
$107
This Frontier deal was found by Cheapflights users on 5/19. 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.
qui 6/118:36 pm
ONT
- SFO
Nonstop1h 37m
Frontier
qui 6/189:41 am
SFO
- ONT
Nonstop1h 32m
Frontier
Deal found 5/19![Frontier logo]()
$108
This Kiwi.com deal was found by Cheapflights users on 5/17. 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.
dom 6/1411:58 am
ONT
- LAS
Nonstop1h 08m
Frontier
ter 6/168:00 am
LAS
- ONT
Nonstop1h 07m
Frontier
Deal found 5/17![Frontier logo]()
$96
This Super.com deal was found by Cheapflights users on 5/18. 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 Super.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
ter 6/163:34 pm
ONT
- LAS
Nonstop1h 12m
Frontier
sex 6/191:55 pm
LAS
- ONT
Nonstop1h 13m
Frontier
Deal found 5/18![Frontier logo]()
$92
This Frontier deal was found by Cheapflights users on 5/20. 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.
ter 6/161:33 pm
ONT
- LAS
Nonstop1h 11m
Frontier
seg 6/221:55 pm
LAS
- ONT
Nonstop1h 13m
Frontier
Deal found 5/20![Frontier logo]()
$93
This Frontier deal was found by Cheapflights users on 5/16. 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 Frontier is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
ter 6/163:34 pm
ONT
- LAS
Nonstop1h 12m
Frontier
sex 7/176:46 pm
LAS
- ONT
Nonstop1h 07m
Frontier
Deal found 5/16![Frontier logo]()
$102
This Super.com deal was found by Cheapflights users on 5/18. 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 Super.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
seg 6/2211:58 am
ONT
- LAS
Nonstop1h 08m
Frontier
ter 6/231:55 pm
LAS
- ONT
Nonstop1h 13m
Frontier
Deal found 5/18![Frontier logo]()
$103
This iWofly deal was found by Cheapflights users on 5/19. 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 iWofly is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
qua 6/243:34 pm
ONT
- LAS
Nonstop1h 12m
Frontier
sex 7/31:55 pm
LAS
- ONT
Nonstop1h 13m
Frontier
Deal found 5/19![Frontier logo]()
$109
This Kiwi.com deal was found by Cheapflights users on 5/17. 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.
qui 6/2511:58 am
ONT
- LAS
Nonstop1h 08m
Frontier
qua 7/16:43 pm
LAS
- ONT
Nonstop1h 08m
Frontier
Deal found 5/17![Frontier logo]()
$101
This Frontier deal was found by Cheapflights users on 5/19. 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.
dom 6/283:34 pm
ONT
- LAS
Nonstop1h 12m
Frontier
qua 7/11:55 pm
LAS
- ONT
Nonstop1h 13m
Frontier
Deal found 5/19![Frontier logo]()
$108
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 maio 21, 2026.
Search for one-way flight options from Ontario to USA. Find affordable one-way fares based on user searches. Data last updated maio 21, 2026.
This Super.com deal was found by Cheapflights users on 5/18. 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 Super.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
ter 8/186:00 am
ONT
- DEN
Nonstop2h 26m
Frontier
Deal found 5/18![Frontier logo]()
$26
This Kiwi.com deal was found by Cheapflights users on 5/18. 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
ter 7/146:00 am
ONT
- DEN
Nonstop2h 24m
Frontier
Deal found 5/18![Frontier logo]()
$27
This Cheapflightsfares deal was found by Cheapflights users on 5/19. 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.
qua 8/126:00 am
ONT
- DEN
Nonstop2h 24m
Frontier
Deal found 5/19![Frontier logo]()
$28
This Super.com deal was found by Cheapflights users on 5/21. 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.
ter 7/286:00 am
ONT
- DEN
Nonstop2h 24m
Frontier
Deal found 5/21![Frontier logo]()
$33
This Trip.com deal was found by Cheapflights users on 5/20. 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.
ter 8/111:28 pm
ONT
- LAS
Nonstop1h 11m
Frontier
Deal found 5/20![Frontier logo]()
$35
This Kiwi.com deal was found by Cheapflights users on 5/21. 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
sáb 8/1511:43 am
ONT
- LAS
Nonstop1h 10m
Frontier
Deal found 5/21![Frontier logo]()
$36
This CheapOair deal was found by Cheapflights users on 5/18. 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 CheapOair is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
ter 6/236:00 am
ONT
- DEN
Nonstop2h 26m
Frontier
Deal found 5/18![Frontier logo]()
$40
This Super.com deal was found by Cheapflights users on 5/20. 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.
qua 6/246:00 am
ONT
- DEN
Nonstop2h 26m
Frontier
Deal found 5/20![Frontier logo]()
$44
This Super.com deal was found by Cheapflights users on 5/20. 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.
qui 9/311:43 am
ONT
- LAS
Nonstop1h 08m
Frontier
Deal found 5/20![Frontier logo]()
$47
This Frontier deal was found by Cheapflights users on 5/19. 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.
qui 8/63:40 pm
ONT
- LAS
Nonstop1h 11m
Frontier
Deal found 5/19![Frontier logo]()
$48
This Trip.com deal was found by Cheapflights users on 5/20. 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.
qui 8/203:34 pm
ONT
- LAS
Nonstop1h 12m
Frontier
Deal found 5/20![Frontier logo]()
$50
This Mytrip deal was found by Cheapflights users on 5/21. 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 Mytrip is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
qui 10/292:58 pm
ONT
- LAS
Nonstop1h 10m
Frontier
Deal found 5/21![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 maio 21, 2026.
Most accurate provider | FlightHub 3 stars |
|---|---|
Most trusted provider | FlightHub 3 stars |
Round-trip from | $74 (Kiwi.com) |
One-way from | $26 (Super.com) |
Popular in | May |
Cheapest in | January |
Average price | $393 |
Good round-trip deal | $156 or less |
Good one-way deal | $88 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 maio 21, 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
OntarioDenver
ONT - DEN
ONTDEN
Ontario
sáb 8/15
5:50 am-12:30 pm
2 stops5h 40m
Denver Intl
ter 8/18
8:40 pm-10:00 pm
Nonstop2h 20m
$172
OntarioSan Francisco
ONT - SFO
ONTSFO
Ontario
qua 8/26
1:10 pm-7:05 pm
2 stops5h 55m
San Francisco
sáb 8/29
5:00 am-8:45 am
1 stop3h 45m
$182
OntarioDenver
ONT - DEN
ONTDEN
Ontario
ter 8/18
1:15 pm-7:50 pm
1 stop5h 35m
Denver Intl
qui 8/20
9:45 am-3:05 pm
2 stops6h 20m
$182
OntarioLas Vegas
ONT - LAS
ONTLAS
Ontario
qui 9/10
6:10 am-11:25 am
2 stops5h 15m
Las Vegas Harry Reid Intl
seg 9/14
6:20 pm-7:25 pm
Nonstop1h 05m
$192
OntarioDenver
ONT - DEN
ONTDEN
Ontario
seg 8/10
12:55 pm-8:01 pm
1 stop6h 06m
Denver Intl
ter 8/11
6:18 pm-11:34 pm
1 stop6h 16m
$197
OntarioDenver
ONT - DEN
ONTDEN
Ontario
ter 7/7
1:00 pm-8:01 pm
1 stop6h 01m
Denver Intl
ter 7/14
5:40 am-8:47 am
1 stop4h 07m
$197
OntarioDenver
ONT - DEN
ONTDEN
Ontario
qui 8/6
12:55 pm-8:01 pm
1 stop6h 06m
Denver Intl
sáb 8/8
6:49 am-12:05 pm
1 stop6h 16m
$197
OntarioDenver
ONT - DEN
ONTDEN
Ontario
qua 8/19
6:00 am-12:04 pm
1 stop5h 04m
Denver Intl
sáb 8/22
6:18 pm-10:05 pm
1 stop4h 47m
$197
OntarioDenver
ONT - DEN
ONTDEN
Ontario
qua 7/8
1:00 pm-8:01 pm
1 stop6h 01m
Denver Intl
ter 7/14
7:09 pm-11:48 pm
1 stop5h 39m
$197
Quickest round-trip
OntarioSan Francisco
ONT - SFO
ONTSFO
Ontario
ter 6/23
6:00 am-7:25 am
Nonstop1h 25m
San Francisco
ter 6/23
10:40 am-12:12 pm
Nonstop1h 32m
$202
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-DEN
ONT-LAS
ONT-SFO
ONT-SEA
ONT-JFK
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-DEN
ONT-LAS
ONT-SFO
ONT-SEA
What is the cheapest month to book a flight from Ontario to USA?
Currently, August is the cheapest month in which you can book a flight from Ontario to USA (average of $274). Flying from Ontario to USA in March is currently the most expensive (average of $395). 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 maio 21, 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 25% on your trip compared to booking a flight in the afternoon.
How often are flights from Ontario to the United States delayed?
About 13% of weekly flights between Ontario and United States have experienced delays in the past year, with the average delay time being 126 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 4% of flights being delayed.
How far ahead should I book a flight from Ontario to USA?
Booking 37 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 May 16, 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. Tuesday evenings 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 maio 21, 2026.
Read reviews from past customers who have flown Alaska Airlines,Southwest, 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.
Boarding
8.1
Comfort
7.8
Overall
7.9
Food
7.0
Entertainment
7.0
Crew
8.5
Reviews
1 / 20
10.0
ExcellentFranzi,Mar 2026
SFO - PDX
Boarding
8.1
Comfort
7.8
Overall
7.9
Food
7.0
Entertainment
7.0
Crew
8.5
Reviews
1 / 20
10.0
ExcellentFranzi,Mar 2026
SFO - PDX
Boarding
8.1
Comfort
7.8
Overall
7.9
Food
7.0
Entertainment
7.0
Crew
8.5
Reviews
1 / 20
10.0
ExcellentFranzi,Mar 2026
SFO - PDX
Boarding
8.1
Comfort
7.8
Overall
7.9
Food
7.0
Entertainment
7.0
Crew
8.5
Reviews
1 / 20
10.0
ExcellentFranzi,Mar 2026
SFO - PDX
Boarding
8.1
Comfort
7.8
Overall
7.9
Food
7.0
Entertainment
7.0
Crew
8.5
Reviews
1 / 20
10.0
ExcellentFranzi,Mar 2026
SFO - PDX
Boarding
8.1
Comfort
7.8
Overall
7.9
Food
7.0
Entertainment
7.0
Crew
8.5
Reviews
1 / 20
10.0
ExcellentFranzi,Mar 2026
SFO - PDX
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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Alternative routes for Ontario to USA
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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 maio 21, 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 9 airlines flying from Ontario to USA
Discover the top 9 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 maio 21, 2026.
| Airline | Cheapest | Average | Flexibility | On-time |
|---|---|---|---|---|
| Cheapest$27 | Average$141 | FlexibilityNo cancel fee | On-time65% | |
| Cheapest$41 | Average$212 | FlexibilityNo cancel fee | On-time62% | |
| Cheapest$77 | Average$377 | FlexibilityNo cancel fee | On-time69% | |
| Cheapest$78 | Average$310 | FlexibilityNo cancel fee | On-time75% | |
| Cheapest$98 | Average$219 | FlexibilityNo cancel fee | On-time85% | |
| Cheapest$99 | Average$388 | FlexibilityNo cancel fee | On-timeN/A | |
| Cheapest$100 | Average$365 | FlexibilityNo cancel fee | On-time63% | |
| Cheapest$153 | Average$329 | FlexibilityNo cancel fee | On-time62% | |
| Cheapest$182 | Average$410 | FlexibilityNo cancel fee | On-time71% |