$25+ 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 6/3. Fares are subject to change and may not be available on all flights or dates of travel.
ONT — LAX
Jun 11 — Jun 181
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 May 12, 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 May 12, 2026.
This Frontier deal was found by Cheapflights users on 5/10. 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 8/1311:43 am
ONT
- LAS
Nonstop1h 10m
Frontier
Sat 8/156:46 pm
LAS
- ONT
Nonstop1h 07m
Frontier
Deal found 5/10![Frontier logo]()
$75
This Frontier deal was found by Cheapflights users on 5/9. 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 9/53:34 pm
ONT
- LAS
Nonstop1h 12m
Frontier
Thu 9/109:10 am
LAS
- ONT
Nonstop1h 11m
Frontier
Deal found 5/9![Frontier logo]()
$76
This Super.com deal was found by Cheapflights users on 5/10. 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 6/63:30 pm
ONT
- LAS
Nonstop1h 13m
Frontier
Sat 6/131:55 pm
LAS
- ONT
Nonstop1h 13m
Frontier
Deal found 5/10![Frontier logo]()
$86
This Trip.com deal was found by Cheapflights users on 5/11. 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.
Wed 7/81:28 pm
ONT
- LAS
Nonstop1h 11m
Frontier
Sat 7/116:46 pm
LAS
- ONT
Nonstop1h 07m
Frontier
Deal found 5/11![Frontier logo]()
$90
This Frontier deal was found by Cheapflights users on 5/12. 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 9/109:12 pm
ONT
- LAS
Nonstop1h 09m
Frontier
Mon 9/147:45 pm
LAS
- ONT
Nonstop1h 09m
Frontier
Deal found 5/12![Frontier logo]()
$94
This Trip.com deal was found by Cheapflights users on 5/11. 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 8/83:40 pm
ONT
- LAS
Nonstop1h 11m
Frontier
Tue 8/116:46 pm
LAS
- ONT
Nonstop1h 07m
Frontier
Deal found 5/11![Frontier logo]()
$95
This Trip.com deal was found by Cheapflights users on 5/8. 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 8/1311:43 am
ONT
- LAS
Nonstop1h 10m
Frontier
Mon 8/176:46 pm
LAS
- ONT
Nonstop1h 07m
Frontier
Deal found 5/8![Frontier logo]()
$97
This Kiwi.com deal was found by Cheapflights users on 5/11. 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 6/28:17 pm
ONT
- LAS
1 stop28h 15m
Frontier
Tue 6/96:43 pm
LAS
- ONT
Nonstop1h 08m
Frontier
Deal found 5/11![Frontier logo]()
$99
This Kiwi.com deal was found by Cheapflights users on 5/10. 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 6/98:36 pm
ONT
- LAS
1 stop28h 08m
Frontier
Tue 6/168:00 am
LAS
- ONT
Nonstop1h 07m
Frontier
Deal found 5/10![Frontier logo]()
$101
This Super.com deal was found by Cheapflights users on 5/10. 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 6/73:30 pm
ONT
- LAS
Nonstop1h 13m
Frontier
Wed 6/106:43 pm
LAS
- ONT
Nonstop1h 08m
Frontier
Deal found 5/10![Frontier logo]()
$102
This Super.com deal was found by Cheapflights users on 5/10. 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 6/1411:58 am
ONT
- LAS
Nonstop1h 08m
Frontier
Tue 6/168:00 am
LAS
- ONT
Nonstop1h 07m
Frontier
Deal found 5/10![Frontier logo]()
$103
This Super.com deal was found by Cheapflights users on 5/11. 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 6/213:34 pm
ONT
- LAS
Nonstop1h 12m
Frontier
Wed 6/241:55 pm
LAS
- ONT
Nonstop1h 13m
Frontier
Deal found 5/11![Frontier logo]()
$104
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 May 12, 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 May 12, 2026.
This Southwest deal was found by Cheapflights users on 5/10. 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 6/97:20 pm
ONT
- LAS
1 stop3h 45m
Southwest
Tue 6/1611:20 am
LAS
- ONT
1 stop5h 45m
Southwest
Deal found 5/10![Southwest logo]()
$137
This United Airlines deal was found by Cheapflights users on 5/11. 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 6/31:50 pm
ONT
- SFO
Nonstop1h 25m
United Airlines
Mon 6/810:40 am
SFO
- ONT
Nonstop1h 32m
United Airlines
Deal found 5/11![United Airlines logo]()
$147
This Delta deal was found by Cheapflights users on 5/7. 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.
Thu 6/46:00 am
ONT
- DEN
1 stop4h 45m
Delta
Mon 6/85:40 am
DEN
- ONT
1 stop4h 10m
Delta
Deal found 5/7![Delta logo]()
$209
This Alaska Airlines deal was found by Cheapflights users on 5/10. 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.
Tue 6/27:41 pm
ONT
- SEA
Nonstop2h 49m
Alaska Airlines
Tue 6/99:22 pm
SEA
- ONT
Nonstop2h 36m
Alaska Airlines
Deal found 5/10![Alaska Airlines logo]()
$262
This Southwest deal was found by Cheapflights users on 5/10. 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 6/23:45 pm
ONT
- LAS
1 stop4h 00m
Southwest
Wed 6/33:10 pm
LAS
- ONT
1 stop3h 45m
Southwest
Deal found 5/10![Southwest logo]()
$137
This Southwest deal was found by Cheapflights users on 5/11. 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 6/166:35 pm
ONT
- DEN
1 stop4h 30m
Southwest
Tue 6/236:00 am
DEN
- ONT
1 stop4h 05m
Southwest
Deal found 5/11![Southwest logo]()
$137
This JetBlue deal was found by Cheapflights users on 5/9. 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 8/1811:50 pm
ONT
- JFK
Nonstop5h 21m
JetBlue
Wed 9/27:30 pm
JFK
- ONT
Nonstop6h 05m
JetBlue
Deal found 5/9![JetBlue logo]()
$307
This Southwest deal was found by Cheapflights users on 5/11. 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 6/175:45 am
ONT
- DEN
Nonstop2h 10m
Southwest
Wed 6/248:05 pm
DEN
- ONT
1 stop3h 55m
Southwest
Deal found 5/11![Southwest logo]()
$167
This Southwest deal was found by Cheapflights users on 5/7. 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 6/83:40 pm
ONT
- DEN
1 stop4h 20m
Southwest
Wed 6/106:25 pm
DEN
- ONT
1 stop5h 35m
Southwest
Deal found 5/7![Southwest logo]()
$172
This United Airlines deal was found by Cheapflights users on 5/10. 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 6/166:00 am
ONT
- SFO
Nonstop1h 25m
United Airlines
Tue 6/169:00 pm
SFO
- ONT
Nonstop1h 37m
United Airlines
Deal found 5/10![United Airlines logo]()
$237
This KAYAK deal was found by Cheapflights users on 5/11. 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 6/25:44 am
ONT
- EWR
2 stops13h 24m
American Airlines
Sat 6/65:47 am
EWR
- ONT
1 stop9h 04m
American Airlines
Deal found 5/11![American Airlines logo]()
$482
This Southwest deal was found by Cheapflights users on 5/7. 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 6/16:00 pm
ONT
- SFO
1 stop6h 10m
Southwest
Wed 6/32:50 pm
SFO
- ONT
1 stop6h 55m
Southwest
Deal found 5/7![Southwest logo]()
$177
This Delta deal was found by Cheapflights users on 5/10. 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.
Wed 6/35:50 pm
ONT
- SEA
Nonstop3h 00m
Delta
Wed 6/102:35 pm
SEA
- ONT
Nonstop2h 44m
Delta
Deal found 5/10![Delta logo]()
$262
This United Airlines deal was found by Cheapflights users on 5/8. 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 6/41:50 pm
ONT
- SFO
Nonstop1h 25m
United Airlines
Sat 6/69:13 pm
SFO
- ONT
Nonstop1h 37m
United Airlines
Deal found 5/8![United Airlines logo]()
$247
This Southwest deal was found by Cheapflights users on 5/8. 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 5/309:25 am
ONT
- LAS
2 stops6h 15m
Southwest
Mon 6/17:35 pm
LAS
- ONT
Nonstop1h 05m
Southwest
Deal found 5/8![Southwest logo]()
$192
This United Airlines deal was found by Cheapflights users on 5/8. 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 6/46:30 pm
ONT
- DEN
Nonstop2h 21m
United Airlines
Mon 6/87:24 pm
DEN
- ONT
Nonstop2h 22m
United Airlines
Deal found 5/8![United Airlines logo]()
$258
This Delta deal was found by Cheapflights users on 5/11. 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 9/2210:59 pm
ONT
- HOU
1 stop8h 16m
Delta
Tue 10/1310:05 am
HOU
- ONT
1 stop10h 13m
Delta
Deal found 5/11![Delta logo]()
$297
This Alaska Airlines deal was found by Cheapflights users on 5/11. 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 11/74:09 pm
ONT
- EWR
1 stop10h 55m
Alaska Airlines
Wed 11/115:41 pm
EWR
- ONT
1 stop9h 08m
Alaska Airlines
Deal found 5/11![Alaska Airlines logo]()
$338
This JetBlue deal was found by Cheapflights users on 5/11. 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 8/911:50 pm
ONT
- JFK
Nonstop5h 21m
JetBlue
Fri 8/147:30 pm
JFK
- ONT
Nonstop6h 05m
JetBlue
Deal found 5/11![JetBlue logo]()
$355
This United Airlines deal was found by Cheapflights users on 5/11. 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 9/191:18 pm
ONT
- DEN
Nonstop2h 20m
United Airlines
Thu 10/16:00 am
DEN
- ONT
1 stop5h 03m
United Airlines
Deal found 5/11![United Airlines logo]()
$267
This Southwest deal was found by Cheapflights users on 5/7. 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 6/48:50 pm
ONT
- LAS
1 stop3h 00m
Southwest
Sat 6/612:30 pm
LAS
- ONT
2 stops9h 25m
Southwest
Deal found 5/7![Southwest logo]()
$202
This Delta deal was found by Cheapflights users on 5/8. 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 6/161:00 pm
ONT
- JFK
1 stop7h 52m
Delta
Sat 6/206:00 am
JFK
- ONT
1 stop7h 40m
Delta
Deal found 5/8![Delta logo]()
$298
This Alaska Airlines deal was found by Cheapflights users on 5/10. 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 6/74:03 pm
ONT
- SEA
Nonstop2h 49m
Alaska Airlines
Sun 6/79:22 pm
SEA
- ONT
Nonstop2h 36m
Alaska Airlines
Deal found 5/10![Alaska Airlines logo]()
$347
This Southwest deal was found by Cheapflights users on 5/10. 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 6/94:10 pm
ONT
- LAS
Nonstop1h 10m
Southwest
Fri 6/124:45 pm
LAS
- ONT
2 stops4h 45m
Southwest
Deal found 5/10![Southwest logo]()
$208
This Delta deal was found by Cheapflights users on 5/9. 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 5/301:35 pm
ONT
- SEA
Nonstop3h 00m
Delta
Mon 6/12:30 pm
SEA
- ONT
Nonstop2h 38m
Delta
Deal found 5/9![Delta logo]()
$308
This Alaska Airlines deal was found by Cheapflights users on 5/10. 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 9/2410:45 am
ONT
- SEA
1 stop5h 44m
Alaska Airlines
Sun 9/2710:34 am
SEA
- ONT
1 stop5h 03m
Alaska Airlines
Deal found 5/10![Alaska Airlines logo]()
$347
This JetBlue deal was found by Cheapflights users on 5/7. 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 6/810:41 pm
ONT
- JFK
Nonstop5h 29m
JetBlue
Thu 6/117:37 pm
JFK
- ONT
Nonstop6h 06m
JetBlue
Deal found 5/7![JetBlue logo]()
$397
This Southwest deal was found by Cheapflights users on 5/9. 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 8/76:10 am
ONT
- LAS
2 stops5h 15m
Southwest
Tue 8/117:50 am
LAS
- ONT
Nonstop1h 05m
Southwest
Deal found 5/9![Southwest logo]()
$208
This United Airlines deal was found by Cheapflights users on 5/7. 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 5/306:39 pm
ONT
- SEA
1 stop6h 34m
United Airlines
Sun 5/317:00 am
SEA
- ONT
1 stop5h 12m
United Airlines
Deal found 5/7![United Airlines logo]()
$307
This Alaska Airlines deal was found by Cheapflights users on 5/11. 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 8/175:32 pm
ONT
- SEA
1 stop4h 55m
Alaska Airlines
Mon 8/319:59 am
SEA
- ONT
1 stop6h 11m
Alaska Airlines
Deal found 5/11![Alaska Airlines logo]()
$347
Last-minute flights from Ontario to USADiscover last-minute flight deals from Ontario to USA. Data last updated May 12, 2026 and is based on user searches.
Discover last-minute flight deals from Ontario to USA. Data last updated May 12, 2026 and is based on user searches.
This Super.com deal was found by Cheapflights users on 5/11. 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 5/3111:51 am
ONT
- LAS
Nonstop1h 11m
Frontier
Mon 6/11:59 pm
LAS
- ONT
Nonstop1h 10m
Frontier
Deal found 5/11![Frontier logo]()
$106
This Frontier deal was found by Cheapflights users on 5/10. 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.
Sun 5/313:30 pm
ONT
- LAS
Nonstop1h 13m
Frontier
Tue 6/22:32 pm
LAS
- ONT
Nonstop1h 12m
Frontier
Deal found 5/10![Frontier logo]()
$107
This Frontier deal was found by Cheapflights users on 5/7. 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 6/111:51 am
ONT
- LAS
Nonstop1h 11m
Frontier
Mon 6/16:22 pm
LAS
- ONT
Nonstop1h 10m
Frontier
Deal found 5/7![Frontier logo]()
$105
This Kiwi.com deal was found by Cheapflights users on 5/11. 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 6/28:17 pm
ONT
- LAS
1 stop28h 15m
Frontier
Tue 6/96:43 pm
LAS
- ONT
Nonstop1h 08m
Frontier
Deal found 5/11![Frontier logo]()
$99
This Super.com deal was found by Cheapflights users on 5/12. 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 6/48:17 pm
ONT
- SFO
Nonstop1h 38m
Frontier
Sun 6/79:34 am
SFO
- ONT
Nonstop1h 32m
Frontier
Deal found 5/12![Frontier logo]()
$108
This Frontier deal was found by Cheapflights users on 5/10. 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 6/611:51 am
ONT
- LAS
Nonstop1h 11m
Frontier
Sat 6/66:22 pm
LAS
- ONT
Nonstop1h 10m
Frontier
Deal found 5/10![Frontier logo]()
$75
This Super.com deal was found by Cheapflights users on 5/10. 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 6/63:30 pm
ONT
- LAS
Nonstop1h 13m
Frontier
Sat 6/131:55 pm
LAS
- ONT
Nonstop1h 13m
Frontier
Deal found 5/10![Frontier logo]()
$86
This Super.com deal was found by Cheapflights users on 5/10. 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 6/73:30 pm
ONT
- LAS
Nonstop1h 13m
Frontier
Wed 6/106:43 pm
LAS
- ONT
Nonstop1h 08m
Frontier
Deal found 5/10![Frontier logo]()
$102
This Kiwi.com deal was found by Cheapflights users on 5/10. 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 6/98:36 pm
ONT
- LAS
1 stop28h 08m
Frontier
Tue 6/168:00 am
LAS
- ONT
Nonstop1h 07m
Frontier
Deal found 5/10![Frontier logo]()
$101
This Super.com deal was found by Cheapflights users on 5/10. 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 6/1411:58 am
ONT
- LAS
Nonstop1h 08m
Frontier
Tue 6/168:00 am
LAS
- ONT
Nonstop1h 07m
Frontier
Deal found 5/10![Frontier logo]()
$103
This Frontier deal was found by Cheapflights users on 5/12. 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 6/163:34 pm
ONT
- LAS
Nonstop1h 12m
Frontier
Fri 6/266:43 pm
LAS
- ONT
Nonstop1h 08m
Frontier
Deal found 5/12![Frontier logo]()
$108
This Super.com deal was found by Cheapflights users on 5/11. 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 6/213:34 pm
ONT
- LAS
Nonstop1h 12m
Frontier
Wed 6/241:55 pm
LAS
- ONT
Nonstop1h 13m
Frontier
Deal found 5/11![Frontier logo]()
$104
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 May 12, 2026.
Search for one-way flight options from Ontario to USA. Find affordable one-way fares based on user searches. Data last updated May 12, 2026.
This Super.com deal was found by Cheapflights users on 5/9. 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 6/36:00 am
ONT
- DEN
Nonstop2h 22m
Frontier
Deal found 5/9![Frontier logo]()
$25
This Kiwi.com deal was found by Cheapflights users on 5/8. 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.
Wed 7/810:49 am
ONT
- DEN
Nonstop2h 21m
Frontier
Deal found 5/8![Frontier logo]()
$27
This Cheapflightsfares deal was found by Cheapflights users on 5/11. 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.
Wed 7/156:00 am
ONT
- DEN
Nonstop2h 24m
Frontier
Deal found 5/11![Frontier logo]()
$28
This Frontier deal was found by Cheapflights users on 5/7. 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.
Wed 8/56:00 am
ONT
- DEN
Nonstop2h 24m
Frontier
Deal found 5/7![Frontier logo]()
$29
This Trip.com deal was found by Cheapflights users on 5/11. 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.
Wed 8/263:34 pm
ONT
- LAS
Nonstop1h 12m
Frontier
Deal found 5/11![Frontier logo]()
$35
This Jetabroad deal was found by Cheapflights users on 5/7. 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 Jetabroad is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 5/276:00 am
ONT
- DEN
Nonstop2h 22m
Frontier
Deal found 5/7![Frontier logo]()
$36
This Super.com deal was found by Cheapflights users on 5/11. 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 6/86:00 am
ONT
- DEN
Nonstop2h 22m
Frontier
Deal found 5/11![Frontier logo]()
$42
This Cheapflightsfares deal was found by Cheapflights users on 5/7. 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.
Wed 6/246:00 am
ONT
- DEN
Nonstop2h 26m
Frontier
Deal found 5/7![Frontier logo]()
$44
This Frontier deal was found by Cheapflights users on 5/11. 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 6/210:50 am
ONT
- DEN
Nonstop2h 22m
Frontier
Deal found 5/11![Frontier logo]()
$46
This Frontier deal was found by Cheapflights users on 5/11. 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 9/311:43 am
ONT
- LAS
Nonstop1h 08m
Frontier
Deal found 5/11![Frontier logo]()
$47
This Trip.com deal was found by Cheapflights users on 5/8. 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 8/1311:43 am
ONT
- LAS
Nonstop1h 10m
Frontier
Deal found 5/8![Frontier logo]()
$49
This Frontier deal was found by Cheapflights users on 5/8. 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 9/1411:16 am
ONT
- LAS
Nonstop1h 11m
Frontier
Deal found 5/8![Frontier logo]()
$53
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 May 12, 2026.
Most accurate provider | FlightHub 3 stars |
|---|---|
Most trusted provider | FlightHub 3 stars |
Round-trip from | $75 (Frontier) |
One-way from | $25 (Super.com) |
Popular in | April |
Cheapest in | January |
Average price | $377 |
Good round-trip deal | $137 or less |
Good one-way deal | $85 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 May 12, 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
OntarioLas Vegas
ONT - LAS
ONTLAS
Ontario
Tue 6/9
7:20 pm-11:05 pm
1 stop3h 45m
Las Vegas Harry Reid Intl
Tue 6/16
11:20 am-5:05 pm
1 stop5h 45m
$137
OntarioLas Vegas
ONT - LAS
ONTLAS
Ontario
Tue 6/2
3:45 pm-7:45 pm
1 stop4h 00m
Las Vegas Harry Reid Intl
Wed 6/3
3:10 pm-6:55 pm
1 stop3h 45m
$137
OntarioDenver
ONT - DEN
ONTDEN
Ontario
Tue 6/16
6:35 pm-12:05 am
1 stop4h 30m
Denver Intl
Tue 6/23
6:00 am-9:05 am
1 stop4h 05m
$137
Quickest round-trip
OntarioSan Francisco
ONT - SFO
ONTSFO
Ontario
Wed 6/3
1:50 pm-3:15 pm
Nonstop1h 25m
San Francisco
Mon 6/8
10:40 am-12:12 pm
Nonstop1h 32m
$147
OntarioDenver
ONT - DEN
ONTDEN
Ontario
Wed 6/17
5:45 am-8:55 am
Nonstop2h 10m
Denver Intl
Wed 6/24
8:05 pm-11:00 pm
1 stop3h 55m
$167
OntarioDenver
ONT - DEN
ONTDEN
Ontario
Mon 6/8
3:40 pm-9:00 pm
1 stop4h 20m
Denver Intl
Wed 6/10
6:25 pm-11:00 pm
1 stop5h 35m
$172
OntarioSan Francisco
ONT - SFO
ONTSFO
Ontario
Mon 6/1
6:00 pm-12:10 am
1 stop6h 10m
San Francisco
Wed 6/3
2:50 pm-9:45 pm
1 stop6h 55m
$177
OntarioLas Vegas
ONT - LAS
ONTLAS
Ontario
Sat 5/30
9:25 am-3:40 pm
2 stops6h 15m
Las Vegas Harry Reid Intl
Mon 6/1
7:35 pm-8:40 pm
Nonstop1h 05m
$192
OntarioLas Vegas
ONT - LAS
ONTLAS
Ontario
Thu 6/4
8:50 pm-11:50 pm
1 stop3h 00m
Las Vegas Harry Reid Intl
Sat 6/6
12:30 pm-9:55 pm
2 stops9h 25m
$202
OntarioLas Vegas
ONT - LAS
ONTLAS
Ontario
Tue 6/9
4:10 pm-5:20 pm
Nonstop1h 10m
Las Vegas Harry Reid Intl
Fri 6/12
4:45 pm-9:30 pm
2 stops4h 45m
$208
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
How far ahead should I book a flight from Ontario to USA?
Booking 29 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 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 $269). Flying from Ontario to USA in March is currently the most expensive (average of $389). 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 May 12, 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 32% on your trip compared to booking a flight in the afternoon.
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 9, 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.
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.
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 May 12, 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
Food
7.0
Boarding
8.1
Crew
8.6
Entertainment
7.5
Overall
8.0
Reviews
1 / 20
10.0
ExcellentWilliam Drew,Nov 2025
SJC - HNL
Comfort
8.0
Food
7.0
Boarding
8.1
Crew
8.6
Entertainment
7.5
Overall
8.0
Reviews
1 / 20
10.0
ExcellentWilliam Drew,Nov 2025
SJC - HNL
Comfort
8.0
Food
7.0
Boarding
8.1
Crew
8.6
Entertainment
7.5
Overall
8.0
Reviews
1 / 20
10.0
ExcellentWilliam Drew,Nov 2025
SJC - HNL
Comfort
8.0
Food
7.0
Boarding
8.1
Crew
8.6
Entertainment
7.5
Overall
8.0
Reviews
1 / 20
10.0
ExcellentWilliam Drew,Nov 2025
SJC - HNL
Comfort
8.0
Food
7.0
Boarding
8.1
Crew
8.6
Entertainment
7.5
Overall
8.0
Reviews
1 / 20
10.0
ExcellentWilliam Drew,Nov 2025
SJC - HNL
Comfort
8.0
Food
7.0
Boarding
8.1
Crew
8.6
Entertainment
7.5
Overall
8.0
Reviews
1 / 20
10.0
ExcellentWilliam Drew,Nov 2025
SJC - HNL
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 May 12, 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 May 12, 2026.
| Airline | Cheapest | Average | Flexibility | On-time |
|---|---|---|---|---|
| Cheapest$24 | Average$141 | FlexibilityNo cancel fee | On-time65% | |
| Cheapest$38 | Average$212 | FlexibilityNo cancel fee | On-time62% | |
| Cheapest$77 | Average$366 | FlexibilityNo cancel fee | On-time69% | |
| Cheapest$78 | Average$319 | FlexibilityNo cancel fee | On-time75% | |
| Cheapest$101 | Average$377 | FlexibilityNo cancel fee | On-time63% | |
| Cheapest$148 | Average$408 | FlexibilityNo cancel fee | On-timeN/A | |
| Cheapest$153 | Average$328 | FlexibilityNo cancel fee | On-time62% | |
| Cheapest$182 | Average$392 | FlexibilityNo cancel fee | On-time71% |