$37+ 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 6/15. Fares are subject to change and may not be available on all flights or dates of travel.
ONT — LAX
May 17 — May 241
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 April 17, 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 April 17, 2026.
This Frontier deal was found by Cheapflights users on 4/12. 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.
Wed 6/241:33 pm
ONT
- LAS
Nonstop1h 11m
Frontier
Wed 6/246:43 pm
LAS
- ONT
Nonstop1h 08m
Frontier
Deal found 4/12![Frontier logo]()
$70
This Super.com deal was found by Cheapflights users on 4/13. Clicking the “Pick Dates” 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 5/213:30 pm
ONT
- LAS
Nonstop1h 13m
Frontier
Fri 5/221:59 pm
LAS
- ONT
Nonstop1h 10m
Frontier
Deal found 4/13![Frontier logo]()
$74
This Frontier deal was found by Cheapflights users on 4/13. Clicking the “Pick Dates” 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 6/2911:58 am
ONT
- LAS
Nonstop1h 08m
Frontier
Fri 7/36:43 pm
LAS
- ONT
Nonstop1h 08m
Frontier
Deal found 4/13![Frontier logo]()
$76
This Kiwi.com deal was found by Cheapflights users on 4/13. Clicking the “Pick Dates” 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 7/81:27 pm
ONT
- LAS
Nonstop1h 11m
Frontier
Fri 7/106:40 pm
LAS
- ONT
Nonstop1h 08m
Frontier
Deal found 4/13![Frontier logo]()
$82
This Super.com deal was found by Cheapflights users on 4/15. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Super.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 7/23:34 pm
ONT
- LAS
Nonstop1h 12m
Frontier
Fri 7/316:40 pm
LAS
- ONT
Nonstop1h 08m
Frontier
Deal found 4/15![Frontier logo]()
$84
This CheapOair deal was found by Cheapflights users on 4/12. 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 CheapOair is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 6/2111:58 am
ONT
- LAS
Nonstop1h 08m
Frontier
Thu 6/256:43 pm
LAS
- ONT
Nonstop1h 08m
Frontier
Deal found 4/12![Frontier logo]()
$85
This Trip.com deal was found by Cheapflights users on 4/13. Clicking the “Pick Dates” 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 6/223:34 pm
ONT
- LAS
Nonstop1h 12m
Frontier
Fri 6/261:55 pm
LAS
- ONT
Nonstop1h 13m
Frontier
Deal found 4/13![Frontier logo]()
$87
This Kiwi.com deal was found by Cheapflights users on 4/13. Clicking the “Pick Dates” 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 6/231:33 pm
ONT
- LAS
Nonstop1h 11m
Frontier
Sat 6/276:43 pm
LAS
- ONT
Nonstop1h 08m
Frontier
Deal found 4/13![Frontier logo]()
$91
This Super.com deal was found by Cheapflights users on 4/12. 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.
Tue 5/1210:50 am
ONT
- DEN
Nonstop2h 22m
Frontier
Wed 5/2010:29 pm
DEN
- ONT
Nonstop2h 20m
Frontier
Deal found 4/12![Frontier logo]()
$91
This Kiwi.com deal was found by Cheapflights users on 4/15. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 5/66:00 am
ONT
- LAS
1 stop7h 44m
Frontier
Fri 5/86:45 am
LAS
- ONT
Nonstop1h 04m
Frontier
Deal found 4/15![Frontier logo]()
$92
This Expedia deal was found by Cheapflights users on 4/12. 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 Expedia is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 5/1310:50 am
ONT
- DEN
Nonstop2h 22m
Frontier
Wed 5/2010:29 pm
DEN
- ONT
Nonstop2h 20m
Frontier
Deal found 4/12![Frontier logo]()
$92
This Frontier deal was found by Cheapflights users on 4/14. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Frontier is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 5/66:00 am
ONT
- LAS
1 stop5h 35m
Frontier
Wed 5/62:32 pm
LAS
- ONT
Nonstop1h 12m
Frontier
Deal found 4/14![Frontier logo]()
$93
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 April 17, 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 April 17, 2026.
This Southwest deal was found by Cheapflights users on 4/13. Clicking the “Pick Dates” 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 5/53:30 pm
ONT
- LAS
1 stop4h 05m
Southwest
Wed 5/610:10 am
LAS
- ONT
1 stop5h 00m
Southwest
Deal found 4/13![Southwest logo]()
$117
This Delta deal was found by Cheapflights users on 4/12. 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 Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 6/165:24 pm
ONT
- DEN
1 stop4h 17m
Delta
Tue 6/2312:43 pm
DEN
- ONT
1 stop4h 59m
Delta
Deal found 4/12![Delta logo]()
$197
This Alaska Airlines deal was found by Cheapflights users on 4/14. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Alaska Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 5/83:26 pm
ONT
- SEA
Nonstop2h 51m
Alaska Airlines
Sun 5/107:05 am
SEA
- ONT
Nonstop2h 40m
Alaska Airlines
Deal found 4/14![Alaska Airlines logo]()
$217
This United Airlines deal was found by Cheapflights users on 4/13. Clicking the “Pick Dates” 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.
Sun 5/106:00 am
ONT
- SFO
Nonstop1h 29m
United Airlines
Tue 5/129:23 pm
SFO
- ONT
Nonstop1h 36m
United Airlines
Deal found 4/13![United Airlines logo]()
$218
This Southwest deal was found by Cheapflights users on 4/16. 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.
Mon 5/186:00 am
ONT
- LAS
1 stop4h 50m
Southwest
Wed 5/205:45 am
LAS
- ONT
1 stop4h 40m
Southwest
Deal found 4/16![Southwest logo]()
$157
This JetBlue deal was found by Cheapflights users on 4/16. 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 JetBlue is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 8/2511:50 pm
ONT
- JFK
Nonstop5h 21m
JetBlue
Wed 9/27:30 pm
JFK
- ONT
Nonstop6h 05m
JetBlue
Deal found 4/16![JetBlue logo]()
$347
This Southwest deal was found by Cheapflights users on 4/16. 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.
Sun 6/289:45 am
ONT
- LAS
Nonstop1h 05m
Southwest
Tue 6/3012:45 pm
LAS
- ONT
2 stops5h 50m
Southwest
Deal found 4/16![Southwest logo]()
$167
This Delta deal was found by Cheapflights users on 4/15. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 5/71:29 pm
ONT
- DEN
1 stop4h 46m
Delta
Mon 5/115:30 am
DEN
- ONT
1 stop4h 23m
Delta
Deal found 4/15![Delta logo]()
$221
This Southwest deal was found by Cheapflights users on 4/12. 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 Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 8/2210:15 am
ONT
- LAS
1 stop6h 00m
Southwest
Wed 8/267:50 am
LAS
- ONT
Nonstop1h 05m
Southwest
Deal found 4/12![Southwest logo]()
$184
This United Airlines deal was found by Cheapflights users on 4/15. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 5/66:00 am
ONT
- SFO
Nonstop1h 29m
United Airlines
Sat 5/1610:52 am
SFO
- ONT
Nonstop1h 30m
United Airlines
Deal found 4/15![United Airlines logo]()
$227
This United Airlines deal was found by Cheapflights users on 4/14. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 5/161:30 pm
ONT
- LAS
1 stop5h 11m
United Airlines
Sun 5/175:45 am
LAS
- ONT
1 stop3h 56m
United Airlines
Deal found 4/14![United Airlines logo]()
$234
This Southwest deal was found by Cheapflights users on 4/15. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 5/275:45 am
ONT
- LAS
1 stop3h 30m
Southwest
Wed 5/271:45 pm
LAS
- ONT
1 stop5h 55m
Southwest
Deal found 4/15![Southwest logo]()
$194
This Alaska Airlines deal was found by Cheapflights users on 4/14. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Alaska Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 5/267:41 pm
ONT
- HNL
1 stop31h 16m
Multiple Airlines
Wed 6/31:41 pm
HNL
- ONT
Nonstop5h 36m
Multiple Airlines
Deal found 4/14![Multiple Airlines logo]()
$529
This Alaska Airlines deal was found by Cheapflights users on 4/15. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Alaska Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 5/203:35 pm
ONT
- SEA
1 stop6h 50m
Alaska Airlines
Mon 5/258:30 am
SEA
- ONT
Nonstop2h 40m
Alaska Airlines
Deal found 4/15![Alaska Airlines logo]()
$287
This Delta deal was found by Cheapflights users on 4/13. Clicking the “Pick Dates” 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 5/65:05 pm
ONT
- SEA
1 stop6h 54m
Delta
Sat 5/99:45 am
SEA
- ONT
Nonstop2h 50m
Delta
Deal found 4/13![Delta logo]()
$262
This Southwest deal was found by Cheapflights users on 4/17. 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.
Fri 5/229:55 pm
ONT
- LAS
Nonstop1h 05m
Southwest
Tue 5/265:45 am
LAS
- ONT
1 stop4h 40m
Southwest
Deal found 4/17![Southwest logo]()
$203
This United Airlines deal was found by Cheapflights users on 4/12. 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 United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 5/91:30 pm
ONT
- SFO
Nonstop1h 29m
United Airlines
Mon 5/1110:52 am
SFO
- ONT
Nonstop1h 30m
United Airlines
Deal found 4/12![United Airlines logo]()
$247
This Alaska Airlines deal was found by Cheapflights users on 4/16. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Alaska Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 5/144:03 pm
ONT
- SEA
Nonstop2h 49m
Alaska Airlines
Thu 5/149:22 pm
SEA
- ONT
Nonstop2h 36m
Alaska Airlines
Deal found 4/16![Alaska Airlines logo]()
$292
This United Airlines deal was found by Cheapflights users on 4/16. 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 United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 5/286:00 am
ONT
- SFO
Nonstop1h 25m
United Airlines
Thu 5/289:00 pm
SFO
- ONT
Nonstop1h 37m
United Airlines
Deal found 4/16![United Airlines logo]()
$247
This United Airlines deal was found by Cheapflights users on 4/14. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 5/76:00 am
ONT
- SFO
Nonstop1h 29m
United Airlines
Thu 5/79:23 pm
SFO
- ONT
Nonstop1h 36m
United Airlines
Deal found 4/14![United Airlines logo]()
$247
This Delta deal was found by Cheapflights users on 4/14. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 10/712:00 pm
ONT
- EWR
1 stop7h 58m
Delta
Wed 10/146:55 pm
EWR
- ONT
1 stop7h 53m
Delta
Deal found 4/14![Delta logo]()
$307
This Alaska Airlines deal was found by Cheapflights users on 4/16. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Alaska Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 5/76:00 am
ONT
- SEA
Nonstop2h 50m
Alaska Airlines
Sun 5/179:29 pm
SEA
- ONT
1 stop19h 48m
Alaska Airlines
Deal found 4/16![Alaska Airlines logo]()
$310
This Southwest deal was found by Cheapflights users on 4/15. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 5/309:25 am
ONT
- LAS
2 stops6h 15m
Southwest
Sun 5/317:35 am
LAS
- ONT
1 stop3h 30m
Southwest
Deal found 4/15![Southwest logo]()
$248
This Alaska Airlines deal was found by Cheapflights users on 4/14. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Alaska Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 5/293:35 pm
ONT
- SEA
1 stop23h 49m
Alaska Airlines
Sun 5/319:22 pm
SEA
- ONT
Nonstop2h 36m
Alaska Airlines
Deal found 4/14![Alaska Airlines logo]()
$310
This United Airlines deal was found by Cheapflights users on 4/15. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 5/121:30 pm
ONT
- LAS
1 stop5h 11m
United Airlines
Wed 6/105:30 am
LAS
- ONT
1 stop7h 17m
United Airlines
Deal found 4/15![United Airlines logo]()
$257
This Delta deal was found by Cheapflights users on 4/15. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 7/41:48 pm
ONT
- SEA
Nonstop2h 53m
Delta
Sun 7/1210:05 am
SEA
- ONT
Nonstop2h 57m
Delta
Deal found 4/15![Delta logo]()
$317
This Southwest deal was found by Cheapflights users on 4/13. Clicking the “Pick Dates” 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 6/45:15 am
ONT
- SFO
2 stops6h 05m
Southwest
Mon 6/85:00 am
SFO
- ONT
1 stop5h 00m
Southwest
Deal found 4/13![Southwest logo]()
$253
This Delta deal was found by Cheapflights users on 4/16. 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.
Wed 5/611:53 am
ONT
- SEA
Nonstop3h 04m
Delta
Tue 5/128:25 am
SEA
- ONT
Nonstop2h 47m
Delta
Deal found 4/16![Delta logo]()
$317
This United Airlines deal was found by Cheapflights users on 4/13. Clicking the “Pick Dates” 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.
Sun 5/176:00 am
ONT
- SFO
Nonstop1h 29m
United Airlines
Wed 5/208:10 am
SFO
- ONT
Nonstop1h 31m
United Airlines
Deal found 4/13![United Airlines logo]()
$278
This Alaska Airlines deal was found by Cheapflights users on 4/13. Clicking the “Pick Dates” 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 7/85:54 pm
ONT
- SEA
Nonstop2h 40m
Alaska Airlines
Sun 7/1210:25 am
SEA
- ONT
Nonstop2h 44m
Alaska Airlines
Deal found 4/13![Alaska Airlines logo]()
$337
Last-minute flights from Ontario to USADiscover last-minute flight deals from Ontario to USA. Data last updated April 17, 2026 and is based on user searches.
Discover last-minute flight deals from Ontario to USA. Data last updated April 17, 2026 and is based on user searches.
This Kiwi.com deal was found by Cheapflights users on 4/13. Clicking the “Pick Dates” 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 5/54:39 pm
ONT
- LAS
Nonstop1h 10m
Frontier
Wed 5/62:49 pm
LAS
- ONT
1 stop9h 00m
Frontier
Deal found 4/13![Frontier logo]()
$95
This Kiwi.com deal was found by Cheapflights users on 4/15. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 5/66:00 am
ONT
- LAS
1 stop7h 44m
Frontier
Fri 5/86:45 am
LAS
- ONT
Nonstop1h 04m
Frontier
Deal found 4/15![Frontier logo]()
$92
This Frontier deal was found by Cheapflights users on 4/14. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Frontier is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 5/66:00 am
ONT
- LAS
1 stop5h 35m
Frontier
Wed 5/62:32 pm
LAS
- ONT
Nonstop1h 12m
Frontier
Deal found 4/14![Frontier logo]()
$93
This Southwest deal was found by Cheapflights users on 4/15. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 5/64:30 pm
ONT
- LAS
Nonstop1h 05m
Southwest
Wed 5/69:15 pm
LAS
- ONT
Nonstop1h 00m
Southwest
Deal found 4/15![Southwest logo]()
$97
This Frontier deal was found by Cheapflights users on 4/14. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Frontier is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 5/66:00 am
ONT
- DEN
Nonstop2h 22m
Frontier
Sat 5/1612:34 pm
DEN
- ONT
1 stop7h 58m
Frontier
Deal found 4/14![Frontier logo]()
$98
This Super.com deal was found by Cheapflights users on 4/13. Clicking the “Pick Dates” 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 5/76:00 am
ONT
- DEN
Nonstop2h 22m
Frontier
Mon 5/118:41 am
DEN
- ONT
Nonstop2h 24m
Frontier
Deal found 4/13![Frontier logo]()
$97
This Frontier deal was found by Cheapflights users on 4/14. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Frontier is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 5/74:04 pm
ONT
- LAS
Nonstop1h 10m
Frontier
Sat 5/96:00 am
LAS
- ONT
1 stop11h 04m
Frontier
Deal found 4/14![Frontier logo]()
$98
This Super.com deal was found by Cheapflights users on 4/12. 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.
Tue 5/1210:50 am
ONT
- DEN
Nonstop2h 22m
Frontier
Wed 5/2010:29 pm
DEN
- ONT
Nonstop2h 20m
Frontier
Deal found 4/12![Frontier logo]()
$91
This Kiwi.com deal was found by Cheapflights users on 4/12. 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 5/124:39 pm
ONT
- DEN
1 stop6h 30m
Frontier
Wed 5/1310:29 pm
DEN
- ONT
Nonstop2h 20m
Frontier
Deal found 4/12![Frontier logo]()
$95
This Expedia deal was found by Cheapflights users on 4/12. 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 Expedia is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 5/1310:50 am
ONT
- DEN
Nonstop2h 22m
Frontier
Wed 5/2010:29 pm
DEN
- ONT
Nonstop2h 20m
Frontier
Deal found 4/12![Frontier logo]()
$92
This Super.com deal was found by Cheapflights users on 4/13. Clicking the “Pick Dates” 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 5/213:30 pm
ONT
- LAS
Nonstop1h 13m
Frontier
Fri 5/221:59 pm
LAS
- ONT
Nonstop1h 10m
Frontier
Deal found 4/13![Frontier logo]()
$74
This Frontier deal was found by Cheapflights users on 4/14. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Frontier is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 5/2111:51 am
ONT
- LAS
Nonstop1h 11m
Frontier
Sat 6/61:59 pm
LAS
- ONT
Nonstop1h 10m
Frontier
Deal found 4/14![Frontier logo]()
$76
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 April 17, 2026.
Search for one-way flight options from Ontario to USA. Find affordable one-way fares based on user searches. Data last updated April 17, 2026.
This Kiwi.com deal was found by Cheapflights users on 4/12. 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 6/1511:58 am
ONT
- LAS
Nonstop1h 08m
Frontier
Deal found 4/12![Frontier logo]()
$37
This Super.com deal was found by Cheapflights users on 4/12. 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.
Sun 7/53:34 pm
ONT
- LAS
Nonstop1h 12m
Frontier
Deal found 4/12![Frontier logo]()
$38
This Kiwi.com deal was found by Cheapflights users on 4/14. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 7/1211:43 am
ONT
- LAS
Nonstop1h 08m
Frontier
Deal found 4/14![Frontier logo]()
$46
This Frontier deal was found by Cheapflights users on 4/14. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Frontier is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 5/213:30 pm
ONT
- LAS
Nonstop1h 13m
Frontier
Deal found 4/14![Frontier logo]()
$47
This Southwest deal was found by Cheapflights users on 4/12. 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 Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 5/122:10 pm
ONT
- LAS
Nonstop1h 05m
Southwest
Deal found 4/12![Southwest logo]()
$49
This Southwest deal was found by Cheapflights users on 4/15. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 5/62:25 pm
ONT
- LAS
1 stop5h 20m
Southwest
Deal found 4/15![Southwest logo]()
$59
This Trip.com deal was found by Cheapflights users on 4/12. 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 Trip.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 5/66:00 am
ONT
- ORD
1 stop12h 32m
Frontier
Deal found 4/12![Frontier logo]()
$60
This Kiwi.com deal was found by Cheapflights users on 4/12. 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 6/2611:58 am
ONT
- LAS
Nonstop1h 08m
Frontier
Deal found 4/12![Frontier logo]()
$63
This Kiwi.com deal was found by Cheapflights users on 4/15. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 6/288:36 pm
ONT
- SFO
Nonstop1h 37m
Frontier
Deal found 4/15![Frontier logo]()
$63
This Super.com deal was found by Cheapflights users on 4/12. 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 6/1811:58 am
ONT
- LAS
Nonstop1h 08m
Frontier
Deal found 4/12![Frontier logo]()
$64
This Frontier deal was found by Cheapflights users on 4/16. 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.
Thu 6/188:36 pm
ONT
- SFO
Nonstop1h 37m
Frontier
Deal found 4/16![Frontier logo]()
$64
This Kiwi.com deal was found by Cheapflights users on 4/14. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 6/106:00 am
ONT
- LAS
1 stop11h 29m
Frontier
Deal found 4/14![Frontier logo]()
$65
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 April 17, 2026.
Most accurate provider | FlightHub 3 stars |
|---|---|
Most trusted provider | FlightHub 3 stars |
Round-trip from | $70 (Frontier) |
One-way from | $37 (Kiwi.com) |
Popular in | April |
Cheapest in | January |
Average price | $386 |
Good round-trip deal | $165 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 April 17, 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 5/5
3:30 pm-7:35 pm
1 stop4h 05m
Las Vegas Harry Reid Intl
Wed 5/6
10:10 am-3:10 pm
1 stop5h 00m
$117
OntarioLas Vegas
ONT - LAS
ONTLAS
Ontario
Mon 5/18
6:00 am-10:50 am
1 stop4h 50m
Las Vegas Harry Reid Intl
Wed 5/20
5:45 am-10:25 am
1 stop4h 40m
$157
OntarioLas Vegas
ONT - LAS
ONTLAS
Ontario
Sun 6/28
9:45 am-10:50 am
Nonstop1h 05m
Las Vegas Harry Reid Intl
Tue 6/30
12:45 pm-6:35 pm
2 stops5h 50m
$167
OntarioLas Vegas
ONT - LAS
ONTLAS
Ontario
Sat 8/22
10:15 am-4:15 pm
1 stop6h 00m
Las Vegas Harry Reid Intl
Wed 8/26
7:50 am-8:55 am
Nonstop1h 05m
$184
OntarioLas Vegas
ONT - LAS
ONTLAS
Ontario
Wed 5/27
5:45 am-9:15 am
1 stop3h 30m
Las Vegas Harry Reid Intl
Wed 5/27
1:45 pm-7:40 pm
1 stop5h 55m
$194
OntarioDenver
ONT - DEN
ONTDEN
Ontario
Tue 6/16
5:24 pm-10:41 pm
1 stop4h 17m
Denver Intl
Tue 6/23
12:43 pm-4:42 pm
1 stop4h 59m
$197
OntarioLas Vegas
ONT - LAS
ONTLAS
Ontario
Fri 5/22
9:55 pm-11:00 pm
Nonstop1h 05m
Las Vegas Harry Reid Intl
Tue 5/26
5:45 am-10:25 am
1 stop4h 40m
$203
OntarioSeattle
ONT - SEA
ONTSEA
Ontario
Fri 5/8
3:26 pm-6:17 pm
Nonstop2h 51m
Seattle/Tacoma Intl
Sun 5/10
7:05 am-9:45 am
Nonstop2h 40m
$217
OntarioSan Francisco
ONT - SFO
ONTSFO
Ontario
Sun 5/10
6:00 am-7:29 am
Nonstop1h 29m
San Francisco
Tue 5/12
9:23 pm-10:59 pm
Nonstop1h 36m
$218
OntarioDenver
ONT - DEN
ONTDEN
Ontario
Thu 5/7
1:29 pm-7:15 pm
1 stop4h 46m
Denver Intl
Mon 5/11
5:30 am-8:53 am
1 stop4h 23m
$221
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-LAS
ONT-DEN
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-LAS
ONT-DEN
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 $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 April 17, 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 34% 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 April 11, 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.
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 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 Wednesday 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 April 17, 2026.
Read reviews from past customers who have flown Southwest,Delta, 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.
Food
7.0
Crew
8.6
Boarding
8.1
Entertainment
7.5
Comfort
8.0
Overall
8.0
Reviews
1 / 20
10.0
ExcellentWilliam Drew,Nov 2025
SJC - HNL
Food
7.0
Crew
8.6
Boarding
8.1
Entertainment
7.5
Comfort
8.0
Overall
8.0
Reviews
1 / 20
10.0
ExcellentWilliam Drew,Nov 2025
SJC - HNL
Food
7.0
Crew
8.6
Boarding
8.1
Entertainment
7.5
Comfort
8.0
Overall
8.0
Reviews
1 / 20
10.0
ExcellentWilliam Drew,Nov 2025
SJC - HNL
Food
7.0
Crew
8.6
Boarding
8.1
Entertainment
7.5
Comfort
8.0
Overall
8.0
Reviews
1 / 20
10.0
ExcellentWilliam Drew,Nov 2025
SJC - HNL
Food
7.0
Crew
8.6
Boarding
8.1
Entertainment
7.5
Comfort
8.0
Overall
8.0
Reviews
1 / 20
10.0
ExcellentWilliam Drew,Nov 2025
SJC - HNL
Food
7.0
Crew
8.6
Boarding
8.1
Entertainment
7.5
Comfort
8.0
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
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Ontario and USA flights
Browse other Ontario and USA flight options. Last updated on April 17, 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 April 17, 2026.
| Airline | Cheapest | Average | Flexibility | On-time |
|---|---|---|---|---|
| Cheapest$27 | Average$141 | FlexibilityNo cancel fee | On-time65% | |
| Cheapest$37 | Average$200 | FlexibilityNo cancel fee | On-time62% | |
| Cheapest$68 | Average$377 | FlexibilityNo cancel fee | On-time69% | |
| Cheapest$78 | Average$241 | FlexibilityNo cancel fee | On-time75% | |
| Cheapest$97 | Average$371 | FlexibilityNo cancel fee | On-time63% | |
| Cheapest$98 | Average$224 | FlexibilityNo cancel fee | On-time85% | |
| Cheapest$99 | Average$368 | FlexibilityNo cancel fee | On-timeN/A | |
| Cheapest$155 | Average$324 | FlexibilityNo cancel fee | On-time62% | |
| Cheapest$183 | Average$405 | FlexibilityNo cancel fee | On-time71% |