$45+ Cheap flights from California to Ontario (ONT)
This is the cheapest one-way flight price found by a Cheapflights user in the last 72 hours by searching for a flight departing on 8/10. Fares are subject to change and may not be available on all flights or dates of travel.
LAX — ONT
jun. 20 — jun. 271
Round-trip
1 adult, Economy
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Cheapest flights from California to OntarioExplore the most affordable flight options available from California to Ontario. Find the lowest fares from popular airlines and budget airlines, with prices last updated on mai 21, 2026.
Explore the most affordable flight options available from California to Ontario. Find the lowest fares from popular airlines and budget airlines, with prices last updated on mai 21, 2026.
This Super.com deal was found by Cheapflights users on 5/18. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Super.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
ti. 6/166:43 pm
LAS
- ONT
Nonstop1h 08m
Frontier
ti. 6/231:33 pm
ONT
- LAS
Nonstop1h 11m
Frontier
Deal found 5/18![Frontier logo]()
$51
This Kiwi.com deal was found by Cheapflights users on 5/19. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
ti. 7/216:46 pm
LAS
- ONT
Nonstop1h 07m
Frontier
on. 7/221:28 pm
ONT
- LAS
Nonstop1h 11m
Frontier
Deal found 5/19![Frontier logo]()
$54
This Kiwi.com deal was found by Cheapflights users on 5/16. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
on. 6/106:43 pm
LAS
- ONT
Nonstop1h 08m
Frontier
on. 6/241:33 pm
ONT
- LAS
Nonstop1h 11m
Frontier
Deal found 5/16![Frontier logo]()
$55
This CheapOair deal was found by Cheapflights users on 5/19. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure CheapOair is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
ti. 6/96:43 pm
LAS
- ONT
Nonstop1h 08m
Frontier
ti. 6/163:34 pm
ONT
- LAS
Nonstop1h 12m
Frontier
Deal found 5/19![Frontier logo]()
$56
This Frontier deal was found by Cheapflights users on 5/18. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Frontier is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
ti. 8/116:46 pm
LAS
- ONT
Nonstop1h 07m
Frontier
on. 8/123:40 pm
ONT
- LAS
Nonstop1h 11m
Frontier
Deal found 5/18![Frontier logo]()
$57
This Frontier deal was found by Cheapflights users on 5/20. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Frontier is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
ti. 10/63:00 pm
LAS
- ONT
Nonstop1h 10m
Frontier
ti. 10/2011:16 am
ONT
- LAS
Nonstop1h 11m
Frontier
Deal found 5/20![Frontier logo]()
$58
This Super.com deal was found by Cheapflights users on 5/18. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Super.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
ti. 8/111:56 pm
LAS
- ONT
Nonstop1h 11m
Frontier
to. 8/1311:43 am
ONT
- LAS
Nonstop1h 10m
Frontier
Deal found 5/18![Frontier logo]()
$70
This Frontier deal was found by Cheapflights users on 5/17. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Frontier is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
to. 9/36:40 pm
LAS
- ONT
Nonstop1h 08m
Frontier
on. 9/92:58 pm
ONT
- LAS
Nonstop1h 10m
Frontier
Deal found 5/17![Frontier logo]()
$75
This Frontier deal was found by Cheapflights users on 5/20. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Frontier is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
ti. 10/67:45 pm
LAS
- ONT
Nonstop1h 09m
Frontier
to. 10/1511:16 am
ONT
- LAS
Nonstop1h 11m
Frontier
Deal found 5/20![Frontier logo]()
$76
This Frontier deal was found by Cheapflights users on 5/20. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Frontier is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
to. 10/2212:18 pm
LAS
- ONT
Nonstop1h 13m
Frontier
ti. 10/274:27 pm
ONT
- LAS
Nonstop1h 10m
Frontier
Deal found 5/20![Frontier logo]()
$87
This Super.com deal was found by Cheapflights users on 5/18. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Super.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
ti. 6/96:43 pm
LAS
- ONT
Nonstop1h 08m
Frontier
to. 6/113:34 pm
ONT
- LAS
Nonstop1h 12m
Frontier
Deal found 5/18![Frontier logo]()
$92
This Super.com deal was found by Cheapflights users on 5/18. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Super.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
lø. 7/119:28 am
SFO
- ONT
Nonstop1h 29m
Frontier
ma. 7/138:39 pm
ONT
- SFO
Nonstop1h 30m
Frontier
Deal found 5/18![Frontier logo]()
$93
Best flights from California to OntarioDiscover carefully curated flight deals from California to Ontario that have cost, travel time, and layovers in mind to ensure you get the best travel experience. Data last updated mai 21, 2026.
Discover carefully curated flight deals from California to Ontario that have cost, travel time, and layovers in mind to ensure you get the best travel experience. Data last updated mai 21, 2026.
This Southwest deal was found by Cheapflights users on 5/19. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
ti. 6/1610:25 am
LAS
- ONT
Nonstop1h 05m
Southwest
ti. 6/238:25 pm
ONT
- LAS
Nonstop1h 05m
Southwest
Deal found 5/19![Southwest logo]()
$137
This Alaska Airlines deal was found by Cheapflights users on 5/16. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Alaska Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
lø. 6/65:44 pm
STS
- ONT
Nonstop1h 24m
Alaska Airlines
ti. 6/93:35 pm
ONT
- STS
Nonstop1h 29m
Alaska Airlines
Deal found 5/16![Alaska Airlines logo]()
$137
This United Airlines deal was found by Cheapflights users on 5/17. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
ti. 8/116:00 am
LAS
- ONT
1 stop6h 12m
United Airlines
on. 8/199:01 am
ONT
- LAS
1 stop6h 57m
United Airlines
Deal found 5/17![United Airlines logo]()
$157
This Frontier deal was found by Cheapflights users on 5/16. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Frontier is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
on. 6/38:39 am
LAS
- ONT
1 stop4h 15m
Frontier
lø. 6/68:17 pm
ONT
- LAS
1 stop4h 20m
Frontier
Deal found 5/16![Frontier logo]()
$224
This Southwest deal was found by Cheapflights users on 5/17. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
ti. 8/117:50 am
LAS
- ONT
Nonstop1h 05m
Southwest
on. 8/199:40 am
ONT
- LAS
Nonstop1h 05m
Southwest
Deal found 5/17![Southwest logo]()
$137
This Delta deal was found by Cheapflights users on 5/17. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
ti. 9/17:00 pm
SMF
- ONT
1 stop4h 44m
Delta
to. 9/35:05 pm
ONT
- SMF
1 stop6h 31m
Delta
Deal found 5/17![Delta logo]()
$276
This Southwest deal was found by Cheapflights users on 5/16. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
on. 6/106:30 am
SJC
- ONT
Nonstop1h 20m
Southwest
on. 6/107:20 pm
ONT
- SJC
1 stop4h 05m
Southwest
Deal found 5/16![Southwest logo]()
$147
This Southwest deal was found by Cheapflights users on 5/16. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
ti. 6/92:15 pm
SFO
- ONT
2 stops8h 45m
Southwest
ti. 6/167:20 pm
ONT
- SFO
1 stop4h 05m
Southwest
Deal found 5/16![Southwest logo]()
$162
This United Airlines deal was found by Cheapflights users on 5/17. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
ti. 9/110:37 am
SFO
- ONT
Nonstop1h 35m
United Airlines
ti. 9/156:00 am
ONT
- SFO
Nonstop1h 27m
United Airlines
Deal found 5/17![United Airlines logo]()
$207
This Alaska Airlines deal was found by Cheapflights users on 5/17. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Alaska Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
fr. 7/174:35 pm
STS
- ONT
Nonstop1h 28m
Alaska Airlines
fr. 7/246:43 pm
ONT
- STS
Nonstop1h 31m
Alaska Airlines
Deal found 5/17![Alaska Airlines logo]()
$227
This Southwest deal was found by Cheapflights users on 5/18. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
to. 9/106:40 pm
LAS
- ONT
1 stop3h 25m
Southwest
ti. 9/157:20 am
ONT
- LAS
2 stops6h 05m
Southwest
Deal found 5/18![Southwest logo]()
$182
This Alaska Airlines deal was found by Cheapflights users on 5/17. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Alaska Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
on. 8/54:35 pm
STS
- ONT
Nonstop1h 28m
Alaska Airlines
lø. 8/86:43 pm
ONT
- STS
Nonstop1h 31m
Alaska Airlines
Deal found 5/17![Alaska Airlines logo]()
$227
This Alaska Airlines deal was found by Cheapflights users on 5/20. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Alaska Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
fr. 6/194:35 pm
STS
- ONT
Nonstop1h 28m
Alaska Airlines
lø. 6/206:43 pm
ONT
- STS
Nonstop1h 31m
Alaska Airlines
Deal found 5/20![Alaska Airlines logo]()
$227
This Delta deal was found by Cheapflights users on 5/17. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
to. 8/612:15 pm
RNO
- ONT
1 stop4h 09m
Delta
on. 8/125:06 pm
ONT
- RNO
1 stop6h 46m
Delta
Deal found 5/17![Delta logo]()
$277
This Alaska Airlines deal was found by Cheapflights users on 5/17. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Alaska Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
on. 8/54:35 pm
STS
- ONT
Nonstop1h 28m
Alaska Airlines
ma. 8/106:43 pm
ONT
- STS
Nonstop1h 31m
Alaska Airlines
Deal found 5/17![Alaska Airlines logo]()
$227
This Delta deal was found by Cheapflights users on 5/19. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
to. 8/66:00 am
SMF
- ONT
1 stop6h 05m
Delta
to. 8/136:00 am
ONT
- SMF
1 stop6h 18m
Delta
Deal found 5/19![Delta logo]()
$283
This Southwest deal was found by Cheapflights users on 5/17. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
ti. 7/712:45 pm
LAS
- ONT
2 stops5h 50m
Southwest
ti. 7/144:35 pm
ONT
- LAS
1 stop4h 40m
Southwest
Deal found 5/17![Southwest logo]()
$219
This Alaska Airlines deal was found by Cheapflights users on 5/19. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Alaska Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
to. 8/64:35 pm
STS
- ONT
Nonstop1h 28m
Alaska Airlines
fr. 8/146:43 pm
ONT
- STS
Nonstop1h 31m
Alaska Airlines
Deal found 5/19![Alaska Airlines logo]()
$227
This United Airlines deal was found by Cheapflights users on 5/18. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
lø. 11/74:10 pm
SFO
- ONT
Nonstop1h 37m
United Airlines
fr. 11/201:33 pm
ONT
- SFO
Nonstop1h 29m
United Airlines
Deal found 5/18![United Airlines logo]()
$308
This Delta deal was found by Cheapflights users on 5/18. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
to. 8/612:15 pm
RNO
- ONT
1 stop4h 09m
Delta
ma. 8/109:43 am
ONT
- RNO
1 stop7h 14m
Delta
Deal found 5/18![Delta logo]()
$295
This Southwest deal was found by Cheapflights users on 5/17. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
lø. 8/85:00 am
SFO
- ONT
1 stop3h 45m
Southwest
lø. 8/82:55 pm
ONT
- SFO
1 stop3h 25m
Southwest
Deal found 5/17![Southwest logo]()
$227
This Alaska Airlines deal was found by Cheapflights users on 5/18. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Alaska Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
lø. 10/313:40 pm
STS
- ONT
Nonstop1h 28m
Alaska Airlines
fr. 11/66:31 pm
ONT
- STS
Nonstop1h 36m
Alaska Airlines
Deal found 5/18![Alaska Airlines logo]()
$227
This United Airlines deal was found by Cheapflights users on 5/19. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
lø. 7/114:55 pm
SFO
- ONT
Nonstop1h 38m
United Airlines
ma. 7/136:00 am
ONT
- SFO
Nonstop1h 25m
United Airlines
Deal found 5/19![United Airlines logo]()
$308
This Delta deal was found by Cheapflights users on 5/17. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
fr. 8/76:00 am
RNO
- ONT
1 stop6h 05m
Delta
ma. 8/105:06 pm
ONT
- RNO
1 stop6h 46m
Delta
Deal found 5/17![Delta logo]()
$295
This Southwest deal was found by Cheapflights users on 5/17. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
fr. 6/128:15 pm
SJC
- ONT
Nonstop1h 15m
Southwest
ti. 6/168:55 pm
ONT
- SJC
Nonstop1h 10m
Southwest
Deal found 5/17![Southwest logo]()
$228
This United Airlines deal was found by Cheapflights users on 5/18. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
ti. 6/29:00 pm
SFO
- ONT
Nonstop1h 37m
United Airlines
ti. 6/91:50 pm
ONT
- SFO
Nonstop1h 23m
United Airlines
Deal found 5/18![United Airlines logo]()
$328
This Southwest deal was found by Cheapflights users on 5/17. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
fr. 6/194:40 pm
SJC
- ONT
Nonstop1h 20m
Southwest
ti. 6/235:45 pm
ONT
- SJC
Nonstop1h 15m
Southwest
Deal found 5/17![Southwest logo]()
$228
This Delta deal was found by Cheapflights users on 5/17. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
ti. 8/46:00 am
RNO
- ONT
1 stop6h 05m
Delta
sø. 8/95:06 pm
ONT
- RNO
1 stop6h 46m
Delta
Deal found 5/17![Delta logo]()
$304
This Alaska Airlines deal was found by Cheapflights users on 5/19. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Alaska Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
ma. 9/142:09 pm
STS
- ONT
Nonstop1h 38m
Alaska Airlines
fr. 9/184:27 pm
ONT
- STS
Nonstop1h 40m
Alaska Airlines
Deal found 5/19![Alaska Airlines logo]()
$257
This United Airlines deal was found by Cheapflights users on 5/19. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
ti. 6/306:35 pm
MFR
- ONT
1 stop4h 02m
United Airlines
on. 7/86:00 am
ONT
- MFR
1 stop6h 04m
United Airlines
Deal found 5/19![United Airlines logo]()
$329
Last-minute flights from California to OntarioDiscover last-minute flight deals from California to Ontario. Data last updated mai 21, 2026 and is based on user searches.
Discover last-minute flight deals from California to Ontario. Data last updated mai 21, 2026 and is based on user searches.
This CheapTickets deal was found by Cheapflights users on 5/16. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure CheapTickets is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
lø. 6/65:44 pm
STS
- ONT
Nonstop1h 24m
Alaska Airlines
ti. 6/93:35 pm
ONT
- STS
Nonstop1h 29m
Alaska Airlines
Deal found 5/16![Alaska Airlines logo]()
$130
This CheapOair deal was found by Cheapflights users on 5/19. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure CheapOair is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
ti. 6/96:43 pm
LAS
- ONT
Nonstop1h 08m
Frontier
ti. 6/163:34 pm
ONT
- LAS
Nonstop1h 12m
Frontier
Deal found 5/19![Frontier logo]()
$56
This Super.com deal was found by Cheapflights users on 5/18. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Super.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
ti. 6/96:43 pm
LAS
- ONT
Nonstop1h 08m
Frontier
to. 6/113:34 pm
ONT
- LAS
Nonstop1h 12m
Frontier
Deal found 5/18![Frontier logo]()
$92
This Kiwi.com deal was found by Cheapflights users on 5/16. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
on. 6/106:43 pm
LAS
- ONT
Nonstop1h 08m
Frontier
on. 6/241:33 pm
ONT
- LAS
Nonstop1h 11m
Frontier
Deal found 5/16![Frontier logo]()
$55
This Frontier deal was found by Cheapflights users on 5/20. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Frontier is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
to. 6/111:55 pm
LAS
- ONT
Nonstop1h 13m
Frontier
ti. 6/163:34 pm
ONT
- LAS
Nonstop1h 12m
Frontier
Deal found 5/20![Frontier logo]()
$113
This Kiwi.com deal was found by Cheapflights users on 5/18. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
lø. 6/136:43 pm
LAS
- ONT
Nonstop1h 08m
Frontier
ti. 6/161:33 pm
ONT
- LAS
Nonstop1h 11m
Frontier
Deal found 5/18![Frontier logo]()
$96
This Super.com deal was found by Cheapflights users on 5/18. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Super.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
ti. 6/166:43 pm
LAS
- ONT
Nonstop1h 08m
Frontier
ti. 6/231:33 pm
ONT
- LAS
Nonstop1h 11m
Frontier
Deal found 5/18![Frontier logo]()
$51
This Southwest deal was found by Cheapflights users on 5/18. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
ti. 6/166:20 pm
SJC
- ONT
Nonstop1h 20m
Southwest
on. 6/176:10 am
ONT
- SJC
Nonstop1h 15m
Southwest
Deal found 5/18![Southwest logo]()
$137
This Frontier deal was found by Cheapflights users on 5/20. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Frontier is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
on. 6/171:55 pm
LAS
- ONT
Nonstop1h 13m
Frontier
lø. 6/203:34 pm
ONT
- LAS
Nonstop1h 12m
Frontier
Deal found 5/20![Frontier logo]()
$93
This Frontier deal was found by Cheapflights users on 5/19. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Frontier is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
on. 6/176:43 pm
LAS
- ONT
Nonstop1h 08m
Frontier
fr. 6/193:34 pm
ONT
- LAS
Nonstop1h 12m
Frontier
Deal found 5/19![Frontier logo]()
$108
This Trip.com deal was found by Cheapflights users on 5/20. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Trip.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
on. 6/176:43 pm
LAS
- ONT
Nonstop1h 08m
Frontier
to. 6/183:34 pm
ONT
- LAS
Nonstop1h 12m
Frontier
Deal found 5/20![Frontier logo]()
$116
This Frontier deal was found by Cheapflights users on 5/16. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Frontier is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
ma. 6/296:43 pm
LAS
- ONT
Nonstop1h 08m
Frontier
ti. 6/301:33 pm
ONT
- LAS
Nonstop1h 11m
Frontier
Deal found 5/16![Frontier logo]()
$102
One-way flights from California to OntarioSearch for one-way flight options from California to Ontario. Find affordable one-way fares based on user searches. Data last updated mai 21, 2026.
Search for one-way flight options from California to Ontario. Find affordable one-way fares based on user searches. Data last updated mai 21, 2026.
This Kiwi.com deal was found by Cheapflights users on 5/19. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
ma. 8/106:46 pm
LAS
- ONT
Nonstop1h 07m
Frontier
Deal found 5/19![Frontier logo]()
$45
This Kiwi.com deal was found by Cheapflights users on 5/17. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
lø. 10/313:00 pm
LAS
- ONT
Nonstop1h 10m
Frontier
Deal found 5/17![Frontier logo]()
$46
This Frontier deal was found by Cheapflights users on 5/20. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Frontier is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
lø. 10/33:00 pm
LAS
- ONT
Nonstop1h 10m
Frontier
Deal found 5/20![Frontier logo]()
$47
This Trip.com deal was found by Cheapflights users on 5/20. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Trip.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
to. 9/179:10 am
LAS
- ONT
Nonstop1h 11m
Frontier
Deal found 5/20![Frontier logo]()
$50
This Frontier deal was found by Cheapflights users on 5/19. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Frontier is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
to. 7/239:28 am
SFO
- ONT
Nonstop1h 29m
Frontier
Deal found 5/19![Frontier logo]()
$54
This Frontier deal was found by Cheapflights users on 5/21. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Frontier is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
lø. 8/81:56 pm
LAS
- ONT
Nonstop1h 11m
Frontier
Deal found 5/21![Frontier logo]()
$54
This Frontier deal was found by Cheapflights users on 5/15. 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 Frontier is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
to. 6/189:41 am
SFO
- ONT
Nonstop1h 32m
Frontier
Deal found 5/15![Frontier logo]()
$55
This Frontier deal was found by Cheapflights users on 5/21. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Frontier is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
to. 8/66:46 pm
LAS
- ONT
Nonstop1h 07m
Frontier
Deal found 5/21![Frontier logo]()
$55
This Trip.com deal was found by Cheapflights users on 5/17. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Trip.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
ma. 8/311:56 pm
LAS
- ONT
Nonstop1h 13m
Frontier
Deal found 5/17![Frontier logo]()
$56
This Trip.com deal was found by Cheapflights users on 5/15. 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 Trip.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
lø. 8/19:28 am
SFO
- ONT
Nonstop1h 29m
Frontier
Deal found 5/15![Frontier logo]()
$58
This Kiwi.com deal was found by Cheapflights users on 5/20. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
ma. 6/159:41 am
SFO
- ONT
Nonstop1h 32m
Frontier
Deal found 5/20![Frontier logo]()
$62
This Super.com deal was found by Cheapflights users on 5/18. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Super.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
lø. 9/59:31 am
SFO
- ONT
Nonstop1h 27m
Frontier
Deal found 5/18![Frontier logo]()
$63
Find flight deals from California to Ontario
Keep the following information in mind while searching for California to Ontario flight deals. Data was last updated mai 21, 2026.
Round-trip from | $51 (Super.com) |
|---|---|
One-way from | $45 (Kiwi.com) |
Good round-trip deal | $112 or less |
Good one-way deal | $68 or less |
Cheapflights Fare Finder
Customize your flight search to find flights from California to Ontario 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 mai 21, 2026.
Use the filters below to find and compare flights from California to Ontario that are best for you.
Fly from
Fly to
Route
Depart
Return
Cheapest round-trip
Quickest round-trip
Las VegasOntario
LAS - ONT
LASONT
Las Vegas Harry Reid Intl
ti. 6/16
10:25 am-11:30 am
Nonstop1h 05m
Ontario
ti. 6/23
8:25 pm-9:30 pm
Nonstop1h 05m
$137
Santa RosaOntario
STS - ONT
STSONT
Santa Rosa Sonoma County
lø. 6/6
5:44 pm-7:08 pm
Nonstop1h 24m
Ontario
ti. 6/9
3:35 pm-5:04 pm
Nonstop1h 29m
$137
Las VegasOntario
LAS - ONT
LASONT
Las Vegas Harry Reid Intl
ti. 8/11
7:50 am-8:55 am
Nonstop1h 05m
Ontario
on. 8/19
9:40 am-10:45 am
Nonstop1h 05m
$137
San JoseOntario
SJC - ONT
SJCONT
San Jose
on. 6/10
6:30 am-7:50 am
Nonstop1h 20m
Ontario
on. 6/10
7:20 pm-11:25 pm
1 stop4h 05m
$147
Las VegasOntario
LAS - ONT
LASONT
Las Vegas Harry Reid Intl
ti. 8/11
6:00 am-12:12 pm
1 stop6h 12m
Ontario
on. 8/19
9:01 am-3:58 pm
1 stop6h 57m
$157
San FranciscoOntario
SFO - ONT
SFOONT
San Francisco
ti. 6/9
2:15 pm-11:00 pm
2 stops8h 45m
Ontario
ti. 6/16
7:20 pm-11:25 pm
1 stop4h 05m
$162
Las VegasOntario
LAS - ONT
LASONT
Las Vegas Harry Reid Intl
to. 9/10
6:40 pm-10:05 pm
1 stop3h 25m
Ontario
ti. 9/15
7:20 am-1:25 pm
2 stops6h 05m
$182
San FranciscoOntario
SFO - ONT
SFOONT
San Francisco
ti. 9/1
10:37 am-12:12 pm
Nonstop1h 35m
Ontario
ti. 9/15
6:00 am-7:27 am
Nonstop1h 27m
$207
Las VegasOntario
LAS - ONT
LASONT
Las Vegas Harry Reid Intl
ti. 7/7
12:45 pm-6:35 pm
2 stops5h 50m
Ontario
ti. 7/14
4:35 pm-9:15 pm
1 stop4h 40m
$219
Las VegasOntario
LAS - ONT
LASONT
Las Vegas Harry Reid Intl
on. 6/3
8:39 am-12:54 pm
1 stop4h 15m
Ontario
lø. 6/6
8:17 pm-12:37 am
1 stop4h 20m
$224
Showing 1-10 of 60 resultsSorted by cheapest first
Best time to book a flight from California to Ontario
Have a flexible travel schedule? Discover the best time to fly to Ontario from California with our price prediction graph.
LAS-ONT
STS-ONT
SMF-ONT
SJC-ONT
SFO-ONT
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 California to Ontario
USCA-ONT
LAS-ONT
STS-ONT
SMF-ONT
SJC-ONT
What is the cheapest month to book a flight from California to Ontario?
Currently, January is the cheapest month in which you can book a flight from California to Ontario (average of $19). Flying from California to Ontario in November is currently the most expensive (average of $786). 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 CA to ONT?
Find hourly flight availability from California to Ontario. Discover flight options and departure times throughout the day, allowing you to choose a departure time that suits your schedule. Data last updated mai 21, 2026.
It’s typically best to fly out from California to Ontario in the evening. Doing so could potentially save you 17% on the flight price compared to flying at noon, which is usually more expensive.
How far ahead should I book a flight from California to Ontario?
Booking 77 days in advance of your planned departure date is, on average, the best time to get cheap flights from California to Ontario. The general trend is that the closer you book to the departure date, the more expensive your flight will be.
What is the cheapest day to fly from California to Ontario?
Use this chart to determine the cheapest time to fly round-trip from California to Ontario. Price data was last updated on May 16, 2026.
Travelers seeking maximum savings on their California to Ontario flight should consider departing on Sunday mornings when fares are most often at their lowest. Monday at noon flights should be avoided if possible as fares are typically the most expensive at this time.
Reviews of airlines servicing Ontario
Get insights into the airlines that provide service to Ontario. 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 Ontario. Reviews last updated mai 21, 2026.
See what other customers who have flown with Alaska Airlines,Southwest, andUnited Airlines from California to Ontario have to say. 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
8.5
Boarding
8.1
Comfort
7.8
Overall
7.9
Entertainment
7.0
Reviews
1 / 20
10.0
Excellentrobert,Feb 2026
LAS - SAN
Food
7.0
Crew
8.5
Boarding
8.1
Comfort
7.8
Overall
7.9
Entertainment
7.0
Reviews
1 / 20
10.0
Excellentrobert,Feb 2026
LAS - SAN
Food
7.0
Crew
8.5
Boarding
8.1
Comfort
7.8
Overall
7.9
Entertainment
7.0
Reviews
1 / 20
10.0
Excellentrobert,Feb 2026
LAS - SAN
Food
7.0
Crew
8.5
Boarding
8.1
Comfort
7.8
Overall
7.9
Entertainment
7.0
Reviews
1 / 20
10.0
Excellentrobert,Feb 2026
LAS - SAN
Food
7.0
Crew
8.5
Boarding
8.1
Comfort
7.8
Overall
7.9
Entertainment
7.0
Reviews
1 / 20
10.0
Excellentrobert,Feb 2026
LAS - SAN
Food
7.0
Crew
8.5
Boarding
8.1
Comfort
7.8
Overall
7.9
Entertainment
7.0
Reviews
1 / 20
10.0
Excellentrobert,Feb 2026
LAS - SAN
Related info for your journey
Find useful and relevant information for your journey from California to Ontario. Access travel guides, tips, and recommendations to enhance your travel experience. Get information about local attractions, weather, transportation options, and more.
Browse thousands of different options on Cheapflights for your next trip
Toggle through the tabs below to find thousands of options on Cheapflights for your next trip.
Alternative routes
Complete your trip
Flights by cabin class
Ontario flight routes
Other flight options
Popular flights
Top destinations
Alternative routes for California to Ontario
See prices for flight routes from nearby airports that may be better suited for you.
Complete your trip
Complete your trip to Ontario by adding a car rental and/or hotel reservation to your travel itinerary.
Search flights from California to Ontario by cabin class
Find flights from California to Ontario, based on your preferred cabin class, be it economy, premium economy, business, or first class.
Other flights to Ontario
Explore flights to Ontario departing from other origins. Flights are based on user searches made on Cheapflights and were last updated on mai 21, 2026.
California and Ontario flights
Browse other California and Ontario flight options. Last updated on mai 21, 2026.
Popular flight searches
Check out other popular destinations found by fellow travelers in 2026
California to Ontario flights
Consider these flights traveling from California to Ontario.
Top 6 airlines flying from California to Ontario
Discover the top 6 airlines that operate flights from California to Ontario. 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 mai 21, 2026.
| Airline | Cheapest | Average | Flexibility | On-time |
|---|---|---|---|---|
| Cheapest$39 | Average$162 | FlexibilityNo cancel fee | On-time62% | |
| Cheapest$66 | Average$269 | FlexibilityNo cancel fee | On-timeN/A | |
| Cheapest$68 | Average$254 | FlexibilityNo cancel fee | On-time69% | |
| Cheapest$107 | Average$227 | FlexibilityNo cancel fee | On-time75% | |
| Cheapest$124 | Average$282 | FlexibilityNo cancel fee | On-time63% | |
| Cheapest$186 | Average$274 | FlexibilityNo cancel fee | On-time71% |