$29+ 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 5/19. Fares are subject to change and may not be available on all flights or dates of travel.
ONT — LAX
May 2 — May 91
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 2, 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 2, 2026.
This Kiwi.com deal was found by Cheapflights users on 3/28. Clicking the “Pick Dates” 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 4/139:02 pm
ONT
- LAS
Nonstop1h 12m
Frontier
Tue 4/145:41 pm
LAS
- ONT
Nonstop1h 08m
Frontier
Deal found 3/28![Frontier logo]()
$67
This Frontier deal was found by Cheapflights users on 3/30. Clicking the “Pick Dates” 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 4/147:44 pm
ONT
- LAS
Nonstop1h 10m
Frontier
Tue 4/219:30 am
LAS
- ONT
Nonstop1h 14m
Frontier
Deal found 3/30![Frontier logo]()
$68
This Frontier deal was found by Cheapflights users on 4/1. Clicking the “Pick Dates” 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 6/103:34 pm
ONT
- LAS
Nonstop1h 12m
Frontier
Sun 6/146:40 pm
LAS
- ONT
Nonstop1h 08m
Frontier
Deal found 4/1![Frontier logo]()
$69
This Super.com deal was found by Cheapflights users on 3/30. Clicking the “Pick Dates” 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 4/2011:44 am
ONT
- LAS
Nonstop1h 15m
Frontier
Sat 4/255:41 pm
LAS
- ONT
Nonstop1h 08m
Frontier
Deal found 3/30![Frontier logo]()
$71
This Frontier deal was found by Cheapflights users on 3/28. Clicking the “Pick Dates” 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 4/1811:44 am
ONT
- LAS
Nonstop1h 15m
Frontier
Mon 4/206:59 pm
LAS
- ONT
Nonstop1h 05m
Frontier
Deal found 3/28![Frontier logo]()
$72
This Frontier deal was found by Cheapflights users on 3/28. Clicking the “Pick Dates” 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 4/1211:00 am
ONT
- LAS
Nonstop1h 15m
Frontier
Tue 5/122:32 pm
LAS
- ONT
Nonstop1h 12m
Frontier
Deal found 3/28![Frontier logo]()
$74
This Frontier deal was found by Cheapflights users on 3/30. Clicking the “Pick Dates” 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 5/201:50 pm
ONT
- LAS
Nonstop1h 10m
Frontier
Wed 5/206:22 pm
LAS
- ONT
Nonstop1h 10m
Frontier
Deal found 3/30![Frontier logo]()
$75
This Super.com deal was found by Cheapflights users on 3/30. Clicking the “Pick Dates” 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 4/238:59 pm
ONT
- LAS
Nonstop1h 09m
Frontier
Fri 4/247:59 pm
LAS
- ONT
Nonstop1h 05m
Frontier
Deal found 3/30![Frontier logo]()
$77
This Frontier deal was found by Cheapflights users on 3/30. Clicking the “Pick Dates” 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 4/2711:44 am
ONT
- LAS
Nonstop1h 15m
Frontier
Sat 5/29:30 am
LAS
- ONT
Nonstop1h 14m
Frontier
Deal found 3/30![Frontier logo]()
$78
This Super.com deal was found by Cheapflights users on 3/31. Clicking the “Pick Dates” 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 5/48:59 pm
ONT
- LAS
Nonstop1h 09m
Frontier
Wed 5/62:32 pm
LAS
- ONT
Nonstop1h 12m
Frontier
Deal found 3/31![Frontier logo]()
$79
This Priceline deal was found by Cheapflights users on 3/31. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Priceline is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 5/88:44 am
ONT
- LAS
Nonstop1h 15m
Frontier
Sun 5/101:59 pm
LAS
- ONT
Nonstop1h 10m
Frontier
Deal found 3/31![Frontier logo]()
$80
This Frontier deal was found by Cheapflights users on 3/28. Clicking the “Pick Dates” 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 5/126:00 am
ONT
- DEN
Nonstop2h 22m
Frontier
Tue 5/198:41 am
DEN
- ONT
Nonstop2h 24m
Frontier
Deal found 3/28![Frontier logo]()
$89
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 2, 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 2, 2026.
This Frontier deal was found by Cheapflights users on 4/1. Clicking the “Pick Dates” 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 6/241:27 pm
ONT
- LAS
Nonstop1h 11m
Frontier
Sat 6/277:00 am
LAS
- ONT
1 stop3h 58m
Frontier
Deal found 4/1![Frontier logo]()
$163
This Southwest deal was found by Cheapflights users on 3/28. Clicking the “Pick Dates” 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 4/279:55 pm
ONT
- LAS
Nonstop1h 05m
Southwest
Mon 5/47:20 am
LAS
- ONT
Nonstop1h 05m
Southwest
Deal found 3/28![Southwest logo]()
$177
This Alaska Airlines deal was found by Cheapflights users on 4/1. Clicking the “Pick Dates” 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 5/17:59 pm
ONT
- SEA
Nonstop2h 51m
Alaska Airlines
Sun 5/37:05 am
SEA
- ONT
Nonstop2h 40m
Alaska Airlines
Deal found 4/1![Alaska Airlines logo]()
$177
This United Airlines deal was found by Cheapflights users on 4/1. Clicking the “Pick Dates” 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 4/221:27 pm
ONT
- SFO
Nonstop1h 29m
United Airlines
Sat 5/28:10 am
SFO
- ONT
Nonstop1h 31m
United Airlines
Deal found 4/1![United Airlines logo]()
$217
This Delta deal was found by Cheapflights users on 4/1. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 5/151:29 pm
ONT
- SEA
1 stop5h 19m
Delta
Tue 5/262:30 pm
SEA
- ONT
Nonstop2h 40m
Delta
Deal found 4/1![Delta logo]()
$257
This Southwest deal was found by Cheapflights users on 4/1. Clicking the “Pick Dates” 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 5/58:05 am
ONT
- DEN
1 stop5h 35m
Southwest
Tue 5/126:45 am
DEN
- ONT
2 stops5h 50m
Southwest
Deal found 4/1![Southwest logo]()
$194
This Alaska Airlines deal was found by Cheapflights users on 3/29. Clicking the “Pick Dates” 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 4/2810:39 am
ONT
- SEA
Nonstop2h 51m
Alaska Airlines
Sat 5/27:05 am
SEA
- ONT
Nonstop2h 40m
Alaska Airlines
Deal found 3/29![Alaska Airlines logo]()
$197
This Southwest deal was found by Cheapflights users on 3/28. Clicking the “Pick Dates” 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 4/273:00 pm
ONT
- SFO
2 stops7h 10m
Southwest
Mon 5/45:40 pm
SFO
- ONT
1 stop5h 25m
Southwest
Deal found 3/28![Southwest logo]()
$202
This Alaska Airlines deal was found by Cheapflights users on 3/30. Clicking the “Pick Dates” 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 5/710:39 am
ONT
- SEA
Nonstop2h 51m
Alaska Airlines
Sat 5/97:50 pm
SEA
- ONT
Nonstop2h 42m
Alaska Airlines
Deal found 3/30![Alaska Airlines logo]()
$207
This Southwest deal was found by Cheapflights users on 4/1. Clicking the “Pick Dates” 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 6/15:05 pm
ONT
- SFO
2 stops7h 05m
Southwest
Sat 6/65:00 am
SFO
- ONT
1 stop3h 40m
Southwest
Deal found 4/1![Southwest logo]()
$202
This United Airlines deal was found by Cheapflights users on 3/30. Clicking the “Pick Dates” 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 4/256:00 am
ONT
- SFO
Nonstop1h 29m
United Airlines
Mon 4/2710:50 am
SFO
- ONT
Nonstop1h 30m
United Airlines
Deal found 3/30![United Airlines logo]()
$246
This JetBlue deal was found by Cheapflights users on 3/28. Clicking the “Pick Dates” 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.
Thu 5/1411:25 pm
ONT
- JFK
Nonstop5h 20m
JetBlue
Sun 5/245:30 pm
JFK
- ONT
Nonstop6h 17m
JetBlue
Deal found 3/28![JetBlue logo]()
$522
This United Airlines deal was found by Cheapflights users on 3/28. Clicking the “Pick Dates” 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 4/186:00 am
ONT
- SFO
Nonstop1h 29m
United Airlines
Tue 4/288:25 am
SFO
- ONT
Nonstop1h 31m
United Airlines
Deal found 3/28![United Airlines logo]()
$247
This Southwest deal was found by Cheapflights users on 4/1. Clicking the “Pick Dates” 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 4/303:00 pm
ONT
- SFO
2 stops7h 10m
Southwest
Tue 5/58:55 am
SFO
- ONT
2 stops6h 10m
Southwest
Deal found 4/1![Southwest logo]()
$206
This Delta deal was found by Cheapflights users on 3/28. Clicking the “Pick Dates” 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 4/2512:49 pm
ONT
- JFK
1 stop8h 59m
Delta
Sat 5/26:20 am
JFK
- ONT
1 stop8h 16m
Delta
Deal found 3/28![Delta logo]()
$281
This United Airlines deal was found by Cheapflights users on 3/29. Clicking the “Pick Dates” 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 4/221:27 pm
ONT
- SFO
Nonstop1h 29m
United Airlines
Mon 4/279:09 pm
SFO
- ONT
Nonstop1h 36m
United Airlines
Deal found 3/29![United Airlines logo]()
$247
This Southwest deal was found by Cheapflights users on 3/28. Clicking the “Pick Dates” 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 4/259:25 am
ONT
- LAS
2 stops6h 15m
Southwest
Sat 5/27:05 am
LAS
- ONT
2 stops8h 30m
Southwest
Deal found 3/28![Southwest logo]()
$207
This Delta deal was found by Cheapflights users on 4/1. Clicking the “Pick Dates” 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 5/510:15 pm
ONT
- EWR
1 stop8h 14m
Delta
Sat 5/94:29 pm
EWR
- ONT
1 stop9h 16m
Delta
Deal found 4/1![Delta logo]()
$287
This United Airlines deal was found by Cheapflights users on 3/29. Clicking the “Pick Dates” 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 4/221:27 pm
ONT
- SFO
Nonstop1h 29m
United Airlines
Wed 4/229:09 pm
SFO
- ONT
Nonstop1h 36m
United Airlines
Deal found 3/29![United Airlines logo]()
$247
This Southwest deal was found by Cheapflights users on 3/31. Clicking the “Pick Dates” 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 5/95:30 am
ONT
- SFO
2 stops6h 20m
Southwest
Mon 5/113:00 pm
SFO
- ONT
2 stops5h 40m
Southwest
Deal found 3/31![Southwest logo]()
$207
This Delta deal was found by Cheapflights users on 3/30. Clicking the “Pick Dates” 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.
Mon 4/2710:15 pm
ONT
- JFK
1 stop9h 00m
Delta
Tue 5/52:55 pm
JFK
- ONT
1 stop9h 05m
Delta
Deal found 3/30![Delta logo]()
$298
This Southwest deal was found by Cheapflights users on 3/31. Clicking the “Pick Dates” 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 4/214:30 pm
ONT
- LAS
Nonstop1h 05m
Southwest
Fri 4/2410:15 am
LAS
- ONT
Nonstop1h 05m
Southwest
Deal found 3/31![Southwest logo]()
$223
This Delta deal was found by Cheapflights users on 3/31. Clicking the “Pick Dates” 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 5/210:15 pm
ONT
- JFK
1 stop9h 00m
Delta
Tue 5/1211:10 am
JFK
- ONT
1 stop10h 26m
Delta
Deal found 3/31![Delta logo]()
$309
This Alaska Airlines deal was found by Cheapflights users on 4/1. Clicking the “Pick Dates” 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 4/204:22 pm
ONT
- SEA
1 stop4h 36m
Alaska Airlines
Thu 4/309:17 pm
SEA
- ONT
Nonstop2h 42m
Alaska Airlines
Deal found 4/1![Alaska Airlines logo]()
$347
This Southwest deal was found by Cheapflights users on 3/31. Clicking the “Pick Dates” 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 4/258:40 am
ONT
- DEN
1 stop6h 30m
Southwest
Tue 4/282:05 pm
DEN
- ONT
2 stops5h 50m
Southwest
Deal found 3/31![Southwest logo]()
$224
This United Airlines deal was found by Cheapflights users on 4/1. Clicking the “Pick Dates” 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 4/2611:05 am
ONT
- SFO
Nonstop1h 30m
United Airlines
Wed 4/299:09 pm
SFO
- ONT
Nonstop1h 36m
United Airlines
Deal found 4/1![United Airlines logo]()
$307
This Alaska Airlines deal was found by Cheapflights users on 4/1. Clicking the “Pick Dates” 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 4/1610:33 am
ONT
- SEA
Nonstop2h 50m
Alaska Airlines
Sun 4/267:05 am
SEA
- ONT
Nonstop2h 40m
Alaska Airlines
Deal found 4/1![Alaska Airlines logo]()
$347
This Delta deal was found by Cheapflights users on 3/30. Clicking the “Pick Dates” 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 5/275:50 pm
ONT
- SEA
Nonstop3h 00m
Delta
Sat 5/308:25 am
SEA
- ONT
Nonstop2h 47m
Delta
Deal found 3/30![Delta logo]()
$317
This Alaska Airlines deal was found by Cheapflights users on 3/30. Clicking the “Pick Dates” 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 5/57:00 am
ONT
- SEA
2 stops8h 09m
Alaska Airlines
Wed 5/67:10 am
SEA
- ONT
1 stop7h 09m
Alaska Airlines
Deal found 3/30![Alaska Airlines logo]()
$352
This Southwest deal was found by Cheapflights users on 3/29. Clicking the “Pick Dates” 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 5/145:15 am
ONT
- LAS
1 stop3h 05m
Southwest
Tue 5/265:45 am
LAS
- ONT
1 stop4h 40m
Southwest
Deal found 3/29![Southwest logo]()
$243
Last-minute flights from Ontario to USADiscover last-minute flight deals from Ontario to USA. Data last updated April 2, 2026 and is based on user searches.
Discover last-minute flight deals from Ontario to USA. Data last updated April 2, 2026 and is based on user searches.
This Frontier deal was found by Cheapflights users on 3/28. Clicking the “Pick Dates” 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 4/1211:00 am
ONT
- LAS
Nonstop1h 15m
Frontier
Tue 5/122:32 pm
LAS
- ONT
Nonstop1h 12m
Frontier
Deal found 3/28![Frontier logo]()
$74
This Frontier deal was found by Cheapflights users on 3/30. Clicking the “Pick Dates” 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 4/147:44 pm
ONT
- LAS
Nonstop1h 10m
Frontier
Tue 4/219:30 am
LAS
- ONT
Nonstop1h 14m
Frontier
Deal found 3/30![Frontier logo]()
$68
This Frontier deal was found by Cheapflights users on 3/28. Clicking the “Pick Dates” 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 4/1811:44 am
ONT
- LAS
Nonstop1h 15m
Frontier
Mon 4/206:59 pm
LAS
- ONT
Nonstop1h 05m
Frontier
Deal found 3/28![Frontier logo]()
$72
This Super.com deal was found by Cheapflights users on 3/30. Clicking the “Pick Dates” 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 4/2011:44 am
ONT
- LAS
Nonstop1h 15m
Frontier
Sat 4/255:41 pm
LAS
- ONT
Nonstop1h 08m
Frontier
Deal found 3/30![Frontier logo]()
$71
This Super.com deal was found by Cheapflights users on 3/30. Clicking the “Pick Dates” 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 4/238:59 pm
ONT
- LAS
Nonstop1h 09m
Frontier
Fri 4/247:59 pm
LAS
- ONT
Nonstop1h 05m
Frontier
Deal found 3/30![Frontier logo]()
$77
This Frontier deal was found by Cheapflights users on 3/30. Clicking the “Pick Dates” 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 4/2711:44 am
ONT
- LAS
Nonstop1h 15m
Frontier
Sat 5/29:30 am
LAS
- ONT
Nonstop1h 14m
Frontier
Deal found 3/30![Frontier logo]()
$78
This Trip.com deal was found by Cheapflights users on 4/2. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Trip.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 5/18:20 pm
ONT
- LAS
Nonstop1h 09m
Frontier
Fri 5/86:45 am
LAS
- ONT
Nonstop1h 04m
Frontier
Deal found 4/2![Frontier logo]()
$76
This Frontier deal was found by Cheapflights users on 4/1. Clicking the “Pick Dates” 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 5/27:44 pm
ONT
- LAS
Nonstop1h 10m
Frontier
Mon 5/46:59 pm
LAS
- ONT
Nonstop1h 05m
Frontier
Deal found 4/1![Frontier logo]()
$67
This Super.com deal was found by Cheapflights users on 3/31. Clicking the “Pick Dates” 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 5/48:59 pm
ONT
- LAS
Nonstop1h 09m
Frontier
Wed 5/62:32 pm
LAS
- ONT
Nonstop1h 12m
Frontier
Deal found 3/31![Frontier logo]()
$79
This Frontier deal was found by Cheapflights users on 3/28. Clicking the “Pick Dates” 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 5/126:00 am
ONT
- DEN
Nonstop2h 22m
Frontier
Tue 5/198:41 am
DEN
- ONT
Nonstop2h 24m
Frontier
Deal found 3/28![Frontier logo]()
$89
This Frontier deal was found by Cheapflights users on 3/30. Clicking the “Pick Dates” 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 5/201:50 pm
ONT
- LAS
Nonstop1h 10m
Frontier
Wed 5/206:22 pm
LAS
- ONT
Nonstop1h 10m
Frontier
Deal found 3/30![Frontier logo]()
$75
This Frontier deal was found by Cheapflights users on 4/2. Clicking the “Pick Dates” 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 5/303:30 pm
ONT
- LAS
Nonstop1h 13m
Frontier
Mon 6/11:59 pm
LAS
- ONT
Nonstop1h 10m
Frontier
Deal found 4/2![Frontier logo]()
$66
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 2, 2026.
Search for one-way flight options from Ontario to USA. Find affordable one-way fares based on user searches. Data last updated April 2, 2026.
This Frontier deal was found by Cheapflights users on 3/31. Clicking the “Pick Dates” 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 5/191:50 pm
ONT
- LAS
Nonstop1h 10m
Frontier
Deal found 3/31![Frontier logo]()
$29
This Kiwi.com deal was found by Cheapflights users on 4/1. Clicking the “Pick Dates” 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 4/272:05 pm
ONT
- LAS
Nonstop1h 12m
Frontier
Deal found 4/1![Frontier logo]()
$32
This Frontier deal was found by Cheapflights users on 4/1. Clicking the “Pick Dates” 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 5/27:44 pm
ONT
- LAS
Nonstop1h 10m
Frontier
Deal found 4/1![Frontier logo]()
$33
This Expedia deal was found by Cheapflights users on 3/29. Clicking the “Pick Dates” 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.
Sun 4/269:29 pm
ONT
- LAS
Nonstop1h 12m
Frontier
Deal found 3/29![Frontier logo]()
$34
This Kiwi.com deal was found by Cheapflights users on 3/28. Clicking the “Pick Dates” 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 5/274:39 pm
ONT
- LAS
Nonstop1h 10m
Frontier
Deal found 3/28![Frontier logo]()
$39
This Super.com deal was found by Cheapflights users on 3/31. Clicking the “Pick Dates” 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 5/264:39 pm
ONT
- LAS
Nonstop1h 10m
Frontier
Deal found 3/31![Frontier logo]()
$40
This Flightnetwork deal was found by Cheapflights users on 3/30. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Flightnetwork is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 5/201:50 pm
ONT
- LAS
Nonstop1h 10m
Frontier
Deal found 3/30![Frontier logo]()
$41
This Super.com deal was found by Cheapflights users on 3/31. Clicking the “Pick Dates” 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 4/238:59 pm
ONT
- LAS
Nonstop1h 09m
Frontier
Deal found 3/31![Frontier logo]()
$44
This Frontier deal was found by Cheapflights users on 3/30. Clicking the “Pick Dates” 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 4/2511:44 am
ONT
- LAS
Nonstop1h 15m
Frontier
Deal found 3/30![Frontier logo]()
$45
This Frontier deal was found by Cheapflights users on 4/1. Clicking the “Pick Dates” 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 6/303:34 pm
ONT
- LAS
Nonstop1h 12m
Frontier
Deal found 4/1![Frontier logo]()
$47
This Kiwi.com deal was found by Cheapflights users on 3/28. Clicking the “Pick Dates” 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.
Thu 4/239:10 am
ONT
- SFO
Nonstop1h 40m
Frontier
Deal found 3/28![Frontier logo]()
$68
This Frontier deal was found by Cheapflights users on 3/30. Clicking the “Pick Dates” 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 5/268:17 pm
ONT
- SFO
Nonstop1h 38m
Frontier
Deal found 3/30![Frontier logo]()
$69
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 2, 2026.
Most accurate provider | FlightHub 3 stars |
|---|---|
Most trusted provider | FlightHub 3 stars |
Round-trip from | $67 (Super.com) |
One-way from | $29 (Frontier) |
Popular in | December |
Cheapest in | January |
Average price | $357 |
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 April 2, 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
Wed 6/24
1:27 pm-2:38 pm
Nonstop1h 11m
Las Vegas Harry Reid Intl
Sat 6/27
7:00 am-10:58 am
1 stop3h 58m
$163
Quickest round-trip
OntarioLas Vegas
ONT - LAS
ONTLAS
Ontario
Mon 4/27
9:55 pm-11:00 pm
Nonstop1h 05m
Las Vegas Harry Reid Intl
Mon 5/4
7:20 am-8:25 am
Nonstop1h 05m
$177
OntarioSeattle
ONT - SEA
ONTSEA
Ontario
Fri 5/1
7:59 pm-10:50 pm
Nonstop2h 51m
Seattle/Tacoma Intl
Sun 5/3
7:05 am-9:45 am
Nonstop2h 40m
$177
OntarioDenver
ONT - DEN
ONTDEN
Ontario
Tue 5/5
8:05 am-2:40 pm
1 stop5h 35m
Denver Intl
Tue 5/12
6:45 am-11:35 am
2 stops5h 50m
$194
OntarioSeattle
ONT - SEA
ONTSEA
Ontario
Tue 4/28
10:39 am-1:30 pm
Nonstop2h 51m
Seattle/Tacoma Intl
Sat 5/2
7:05 am-9:45 am
Nonstop2h 40m
$197
OntarioSan Francisco
ONT - SFO
ONTSFO
Ontario
Mon 4/27
3:00 pm-10:10 pm
2 stops7h 10m
San Francisco
Mon 5/4
5:40 pm-11:05 pm
1 stop5h 25m
$202
OntarioSan Francisco
ONT - SFO
ONTSFO
Ontario
Mon 6/1
5:05 pm-12:10 am
2 stops7h 05m
San Francisco
Sat 6/6
5:00 am-8:40 am
1 stop3h 40m
$202
OntarioSan Francisco
ONT - SFO
ONTSFO
Ontario
Thu 4/30
3:00 pm-10:10 pm
2 stops7h 10m
San Francisco
Tue 5/5
8:55 am-3:05 pm
2 stops6h 10m
$206
OntarioSeattle
ONT - SEA
ONTSEA
Ontario
Thu 5/7
10:39 am-1:30 pm
Nonstop2h 51m
Seattle/Tacoma Intl
Sat 5/9
7:50 pm-10:32 pm
Nonstop2h 42m
$207
OntarioLas Vegas
ONT - LAS
ONTLAS
Ontario
Sat 4/25
9:25 am-3:40 pm
2 stops6h 15m
Las Vegas Harry Reid Intl
Sat 5/2
7:05 am-3:35 pm
2 stops8h 30m
$207
Showing 1-10 of 60 resultsSorted by cheapest first
Best time to book a flight from Ontario to USA
Have a flexible travel schedule? Discover the best time to fly to USA from Ontario with our price prediction graph.
ONT-LAS
ONT-SFO
ONT-DEN
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-SFO
ONT-DEN
ONT-SEA
What is the cheapest month to book a flight from Ontario to USA?
Currently, May is the cheapest month in which you can book a flight from Ontario to USA (average of $33). Flying from Ontario to USA in January is currently the most expensive (average of $53). 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 2, 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 March 28, 2026.
Travelers seeking maximum savings on their Ontario to USA flight should consider departing on Saturday 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 123 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 Thursday 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 2, 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.
Overall
8.0
Crew
8.6
Entertainment
7.5
Boarding
8.1
Food
7.0
Comfort
8.0
Reviews
1 / 20
10.0
ExcellentWilliam Drew,Nov 2025
SJC - HNL
Overall
8.0
Crew
8.6
Entertainment
7.5
Boarding
8.1
Food
7.0
Comfort
8.0
Reviews
1 / 20
10.0
ExcellentWilliam Drew,Nov 2025
SJC - HNL
Overall
8.0
Crew
8.6
Entertainment
7.5
Boarding
8.1
Food
7.0
Comfort
8.0
Reviews
1 / 20
10.0
ExcellentWilliam Drew,Nov 2025
SJC - HNL
Overall
8.0
Crew
8.6
Entertainment
7.5
Boarding
8.1
Food
7.0
Comfort
8.0
Reviews
1 / 20
10.0
ExcellentWilliam Drew,Nov 2025
SJC - HNL
Overall
8.0
Crew
8.6
Entertainment
7.5
Boarding
8.1
Food
7.0
Comfort
8.0
Reviews
1 / 20
10.0
ExcellentWilliam Drew,Nov 2025
SJC - HNL
Overall
8.0
Crew
8.6
Entertainment
7.5
Boarding
8.1
Food
7.0
Comfort
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.
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Ontario and USA flights
Browse other Ontario and USA flight options. Last updated on April 2, 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 2, 2026.
| Airline | Cheapest | Average | Flexibility | On-time |
|---|---|---|---|---|
| Cheapest$27 | Average$139 | FlexibilityNo cancel fee | On-time65% | |
| Cheapest$36 | Average$192 | FlexibilityNo cancel fee | On-time62% | |
| Cheapest$65 | Average$364 | FlexibilityNo cancel fee | On-time69% | |
| Cheapest$78 | Average$282 | FlexibilityNo cancel fee | On-time75% | |
| Cheapest$93 | Average$223 | FlexibilityNo cancel fee | On-time85% | |
| Cheapest$97 | Average$355 | FlexibilityNo cancel fee | On-time63% | |
| Cheapest$99 | Average$360 | FlexibilityNo cancel fee | On-timeN/A | |
| Cheapest$155 | Average$323 | FlexibilityNo cancel fee | On-time62% | |
| Cheapest$184 | Average$389 | FlexibilityNo cancel fee | On-time71% |