$69+ Cheap flights from Ontario (ONT) to Washington
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 5/14. Fares are subject to change and may not be available on all flights or dates of travel.
ONT — SEA
May 23 — May 301
Round-trip
1 adult, Economy
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Find cheap flights from Ontario to Washington with Cheapflights
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Cheapest flights from Ontario to WashingtonExplore the most affordable flight options available from Ontario to Washington. Find the lowest fares from popular airlines and budget airlines, with prices last updated on April 23, 2026.
Explore the most affordable flight options available from Ontario to Washington. Find the lowest fares from popular airlines and budget airlines, with prices last updated on April 23, 2026.
This Kiwi.com deal was found by Cheapflights users on 4/20. 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.
Mon 6/14:04 pm
ONT
- SEA
Nonstop3h 01m
Frontier
Tue 6/98:12 pm
SEA
- ONT
1 stop18h 56m
Frontier
Deal found 4/20![Frontier logo]()
$131
This Super.com deal was found by Cheapflights users on 4/20. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Super.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 6/44:04 pm
ONT
- SEA
Nonstop3h 01m
Frontier
Tue 6/2311:53 am
SEA
- ONT
Nonstop2h 46m
Frontier
Deal found 4/20![Frontier logo]()
$132
This Frontier deal was found by Cheapflights users on 4/20. 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.
Sat 6/64:04 pm
ONT
- SEA
Nonstop3h 01m
Frontier
Wed 6/1011:53 am
SEA
- ONT
Nonstop2h 46m
Frontier
Deal found 4/20![Frontier logo]()
$133
This Expedia deal was found by Cheapflights users on 4/20. 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 Expedia is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 6/44:04 pm
ONT
- SEA
Nonstop3h 01m
Frontier
Mon 6/83:19 pm
SEA
- ONT
1 stop8h 30m
Frontier
Deal found 4/20![Frontier logo]()
$134
This Frontier deal was found by Cheapflights users on 4/18. 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.
Thu 6/44:04 pm
ONT
- SEA
Nonstop3h 01m
Frontier
Sun 6/73:19 pm
SEA
- ONT
1 stop18h 46m
Frontier
Deal found 4/18![Frontier logo]()
$135
This Kiwi.com deal was found by Cheapflights users on 4/19. 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.
Thu 6/114:03 pm
ONT
- SEA
Nonstop2h 54m
Frontier
Wed 6/2411:53 am
SEA
- ONT
Nonstop2h 46m
Frontier
Deal found 4/19![Frontier logo]()
$136
This Super.com deal was found by Cheapflights users on 4/20. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Super.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 5/214:04 pm
ONT
- SEA
Nonstop3h 01m
Frontier
Sun 5/3111:51 am
SEA
- ONT
Nonstop2h 44m
Frontier
Deal found 4/20![Frontier logo]()
$137
This Frontier deal was found by Cheapflights users on 4/19. 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.
Thu 5/214:04 pm
ONT
- SEA
Nonstop3h 01m
Frontier
Sun 5/2411:51 am
SEA
- ONT
Nonstop2h 44m
Frontier
Deal found 4/19![Frontier logo]()
$138
This Frontier deal was found by Cheapflights users on 4/20. 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.
Mon 6/14:04 pm
ONT
- SEA
Nonstop3h 01m
Frontier
Mon 6/83:19 pm
SEA
- ONT
1 stop8h 30m
Frontier
Deal found 4/20![Frontier logo]()
$139
This Booking.com deal was found by Cheapflights users on 4/20. 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 Booking.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 5/3010:50 am
ONT
- SEA
1 stop23h 16m
Frontier
Sat 6/611:51 am
SEA
- ONT
Nonstop2h 44m
Frontier
Deal found 4/20![Frontier logo]()
$140
This Frontier deal was found by Cheapflights users on 4/20. 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.
Sat 5/304:04 pm
ONT
- SEA
Nonstop3h 01m
Frontier
Sun 6/711:51 am
SEA
- ONT
Nonstop2h 44m
Frontier
Deal found 4/20![Frontier logo]()
$143
This Kiwi.com deal was found by Cheapflights users on 4/22. Clicking the “Pick Dates” 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 6/43:30 pm
ONT
- BLI
1 stop8h 09m
Multiple Airlines
Mon 6/83:47 pm
BLI
- ONT
1 stop28h 04m
Multiple Airlines
Deal found 4/22![Multiple Airlines logo]()
$170
Best flights from Ontario to WashingtonDiscover carefully curated flight deals from Ontario to Washington that have cost, travel time, and layovers in mind to ensure you get the best travel experience. Data last updated April 23, 2026.
Discover carefully curated flight deals from Ontario to Washington that have cost, travel time, and layovers in mind to ensure you get the best travel experience. Data last updated April 23, 2026.
This Alaska Airlines deal was found by Cheapflights users on 4/22. Clicking the “Pick Dates” 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 5/154:03 pm
ONT
- SEA
Nonstop2h 49m
Alaska Airlines
Wed 5/208:32 am
SEA
- ONT
Nonstop2h 40m
Alaska Airlines
Deal found 4/22![Alaska Airlines logo]()
$207
This Delta deal was found by Cheapflights users on 4/20. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 5/305:55 pm
ONT
- PDX
1 stop4h 45m
Delta
Sun 5/315:30 am
PDX
- ONT
1 stop5h 42m
Delta
Deal found 4/20![Delta logo]()
$217
This Southwest deal was found by Cheapflights users on 4/18. 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.
Sat 5/164:15 pm
ONT
- GEG
1 stop6h 15m
Southwest
Sat 5/236:45 am
GEG
- ONT
2 stops8h 50m
Southwest
Deal found 4/18![Southwest logo]()
$307
This United Airlines deal was found by Cheapflights users on 4/22. Clicking the “Pick Dates” 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 5/146:00 am
ONT
- GEG
1 stop5h 16m
United Airlines
Thu 6/41:41 pm
GEG
- ONT
1 stop7h 01m
United Airlines
Deal found 4/22![United Airlines logo]()
$386
This Alaska Airlines deal was found by Cheapflights users on 4/19. 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.
Sun 5/106:00 am
ONT
- SEA
Nonstop2h 50m
Alaska Airlines
Wed 5/208:32 am
SEA
- ONT
Nonstop2h 40m
Alaska Airlines
Deal found 4/19![Alaska Airlines logo]()
$207
This Delta deal was found by Cheapflights users on 4/21. 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 Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 5/155:50 pm
ONT
- PDX
1 stop6h 05m
Delta
Mon 5/185:30 am
PDX
- ONT
1 stop7h 05m
Delta
Deal found 4/21![Delta logo]()
$218
This Alaska Airlines deal was found by Cheapflights users on 4/19. 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.
Sun 5/107:00 am
ONT
- PDX
Nonstop2h 24m
Alaska Airlines
Sun 5/248:00 am
PDX
- ONT
Nonstop2h 21m
Alaska Airlines
Deal found 4/19![Alaska Airlines logo]()
$217
This Alaska Airlines deal was found by Cheapflights users on 4/22. Clicking the “Pick Dates” 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 5/154:03 pm
ONT
- SEA
Nonstop2h 49m
Alaska Airlines
Sat 5/168:30 am
SEA
- ONT
Nonstop2h 40m
Alaska Airlines
Deal found 4/22![Alaska Airlines logo]()
$217
This Delta deal was found by Cheapflights users on 4/22. Clicking the “Pick Dates” 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 9/195:55 pm
ONT
- PSC
1 stop5h 49m
Delta
Tue 9/225:00 pm
PSC
- ONT
1 stop6h 44m
Delta
Deal found 4/22![Delta logo]()
$299
This Alaska Airlines deal was found by Cheapflights users on 4/20. 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.
Wed 5/207:00 am
ONT
- PDX
Nonstop2h 24m
Alaska Airlines
Wed 5/277:05 am
PDX
- ONT
1 stop12h 03m
Alaska Airlines
Deal found 4/20![Alaska Airlines logo]()
$250
This Southwest deal was found by Cheapflights users on 4/20. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 7/14:35 pm
ONT
- SEA
2 stops6h 55m
Southwest
Wed 7/85:40 am
SEA
- ONT
1 stop3h 55m
Southwest
Deal found 4/20![Southwest logo]()
$342
This Delta deal was found by Cheapflights users on 4/22. Clicking the “Pick Dates” 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 9/185:05 pm
ONT
- PSC
1 stop6h 31m
Delta
Tue 9/225:45 pm
PSC
- ONT
1 stop4h 55m
Delta
Deal found 4/22![Delta logo]()
$299
This Southwest deal was found by Cheapflights users on 4/21. 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 Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 6/33:45 pm
ONT
- SEA
2 stops8h 10m
Southwest
Sun 6/75:00 am
SEA
- ONT
1 stop6h 15m
Southwest
Deal found 4/21![Southwest logo]()
$342
This Alaska Airlines deal was found by Cheapflights users on 4/22. Clicking the “Pick Dates” 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 6/34:03 pm
ONT
- GEG
1 stop5h 15m
Alaska Airlines
Sat 6/66:00 am
GEG
- ONT
1 stop5h 10m
Alaska Airlines
Deal found 4/22![Alaska Airlines logo]()
$260
This Southwest deal was found by Cheapflights users on 4/21. 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 Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 6/174:35 pm
ONT
- SEA
2 stops6h 55m
Southwest
Sat 6/205:15 am
SEA
- ONT
1 stop4h 35m
Southwest
Deal found 4/21![Southwest logo]()
$342
This Alaska Airlines deal was found by Cheapflights users on 4/20. 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.
Sat 5/235:57 pm
ONT
- PDX
Nonstop2h 24m
Alaska Airlines
Tue 5/267:05 am
PDX
- ONT
1 stop12h 03m
Alaska Airlines
Deal found 4/20![Alaska Airlines logo]()
$260
This Delta deal was found by Cheapflights users on 4/21. 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 Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 5/62:20 pm
ONT
- SEA
Nonstop3h 04m
Delta
Tue 5/128:25 am
SEA
- ONT
Nonstop2h 47m
Delta
Deal found 4/21![Delta logo]()
$317
This Southwest deal was found by Cheapflights users on 4/22. Clicking the “Pick Dates” 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 7/156:25 pm
ONT
- SEA
1 stop5h 05m
Southwest
Tue 7/217:30 am
SEA
- ONT
2 stops9h 35m
Southwest
Deal found 4/22![Southwest logo]()
$342
This Alaska Airlines deal was found by Cheapflights users on 4/22. Clicking the “Pick Dates” 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
- PDX
1 stop5h 10m
Alaska Airlines
Sun 5/318:00 am
PDX
- ONT
Nonstop2h 21m
Alaska Airlines
Deal found 4/22![Alaska Airlines logo]()
$267
This Delta deal was found by Cheapflights users on 4/22. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 6/45:50 pm
ONT
- GEG
1 stop4h 59m
Delta
Sun 6/76:20 am
GEG
- ONT
1 stop4h 57m
Delta
Deal found 4/22![Delta logo]()
$329
This Alaska Airlines deal was found by Cheapflights users on 4/20. 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.
Mon 5/116:00 am
ONT
- SEA
Nonstop2h 50m
Alaska Airlines
Thu 5/218:30 am
SEA
- ONT
Nonstop2h 40m
Alaska Airlines
Deal found 4/20![Alaska Airlines logo]()
$272
This Southwest deal was found by Cheapflights users on 4/22. Clicking the “Pick Dates” 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 6/205:40 am
ONT
- GEG
1 stop4h 55m
Southwest
Sat 6/203:20 pm
GEG
- ONT
2 stops6h 40m
Southwest
Deal found 4/22![Southwest logo]()
$366
This Delta deal was found by Cheapflights users on 4/22. Clicking the “Pick Dates” 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 5/216:45 am
ONT
- PDX
1 stop4h 54m
Delta
Sun 5/245:30 am
PDX
- ONT
1 stop5h 42m
Delta
Deal found 4/22![Delta logo]()
$333
This Delta deal was found by Cheapflights users on 4/20. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 8/215:55 pm
ONT
- PSC
1 stop5h 49m
Delta
Sun 8/239:30 am
PSC
- ONT
1 stop6h 44m
Delta
Deal found 4/20![Delta logo]()
$339
This Alaska Airlines deal was found by Cheapflights users on 4/19. 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.
Fri 8/217:57 pm
ONT
- PSC
1 stop14h 15m
Alaska Airlines
Sun 8/235:20 am
PSC
- ONT
1 stop4h 31m
Alaska Airlines
Deal found 4/19![Alaska Airlines logo]()
$299
This Southwest deal was found by Cheapflights users on 4/19. 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.
Thu 5/214:25 pm
ONT
- GEG
2 stops8h 10m
Southwest
Thu 5/281:30 pm
GEG
- ONT
2 stops8h 05m
Southwest
Deal found 4/19![Southwest logo]()
$404
This Delta deal was found by Cheapflights users on 4/23. Clicking the “Pick Dates” 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 7/105:16 pm
ONT
- SEA
1 stop6h 43m
Delta
Mon 7/138:25 am
SEA
- ONT
Nonstop2h 54m
Delta
Deal found 4/23![Delta logo]()
$357
This Alaska Airlines deal was found by Cheapflights users on 4/19. 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.
Wed 5/277:41 pm
ONT
- PSC
1 stop4h 33m
Alaska Airlines
Fri 5/297:17 pm
PSC
- ONT
1 stop4h 41m
Alaska Airlines
Deal found 4/19![Alaska Airlines logo]()
$299
This Alaska Airlines deal was found by Cheapflights users on 4/21. 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 Alaska Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 9/187:57 pm
ONT
- PSC
1 stop14h 22m
Alaska Airlines
Tue 9/225:29 pm
PSC
- ONT
1 stop5h 55m
Alaska Airlines
Deal found 4/21![Alaska Airlines logo]()
$299
This Delta deal was found by Cheapflights users on 4/18. 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.
Sat 5/166:00 am
ONT
- PDX
1 stop6h 26m
Delta
Tue 5/193:30 pm
PDX
- ONT
2 stops8h 04m
Delta
Deal found 4/18![Delta logo]()
$375
Last-minute flights from Ontario to WashingtonDiscover last-minute flight deals from Ontario to Washington. Data last updated April 23, 2026 and is based on user searches.
Discover last-minute flight deals from Ontario to Washington. Data last updated April 23, 2026 and is based on user searches.
This Booking.com deal was found by Cheapflights users on 4/20. 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 Booking.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 5/196:00 am
ONT
- SEA
1 stop27h 49m
Frontier
Fri 5/2911:51 am
SEA
- ONT
Nonstop2h 44m
Frontier
Deal found 4/20![Frontier logo]()
$145
This Kiwi.com deal was found by Cheapflights users on 4/18. 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.
Wed 5/204:39 pm
ONT
- PDX
1 stop17h 41m
Frontier
Mon 5/2511:15 am
PDX
- ONT
1 stop20h 49m
Frontier
Deal found 4/18![Frontier logo]()
$171
This Super.com deal was found by Cheapflights users on 4/20. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Super.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 5/214:04 pm
ONT
- SEA
Nonstop3h 01m
Frontier
Sun 5/3111:51 am
SEA
- ONT
Nonstop2h 44m
Frontier
Deal found 4/20![Frontier logo]()
$137
This Frontier deal was found by Cheapflights users on 4/19. 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.
Thu 5/214:04 pm
ONT
- SEA
Nonstop3h 01m
Frontier
Sun 5/2411:51 am
SEA
- ONT
Nonstop2h 44m
Frontier
Deal found 4/19![Frontier logo]()
$138
This Super.com deal was found by Cheapflights users on 4/21. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Super.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 5/224:04 pm
ONT
- SEA
Nonstop3h 01m
Frontier
Sat 5/3011:51 am
SEA
- ONT
Nonstop2h 44m
Frontier
Deal found 4/21![Frontier logo]()
$147
This Booking.com deal was found by Cheapflights users on 4/22. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Booking.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 5/284:04 pm
ONT
- SEA
Nonstop3h 01m
Frontier
Fri 5/297:50 pm
SEA
- ONT
1 stop14h 15m
Frontier
Deal found 4/22![Frontier logo]()
$146
This CheapOair deal was found by Cheapflights users on 4/19. 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.
Fri 5/294:04 pm
ONT
- SEA
Nonstop3h 01m
Frontier
Sun 5/318:20 pm
SEA
- ONT
1 stop23h 12m
Frontier
Deal found 4/19![Frontier logo]()
$144
This Frontier deal was found by Cheapflights users on 4/20. 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.
Sat 5/304:04 pm
ONT
- SEA
Nonstop3h 01m
Frontier
Wed 6/1011:53 am
SEA
- ONT
Nonstop2h 46m
Frontier
Deal found 4/20![Frontier logo]()
$133
This Frontier deal was found by Cheapflights users on 4/20. 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.
Sat 5/304:04 pm
ONT
- SEA
Nonstop3h 01m
Frontier
Sun 6/73:19 pm
SEA
- ONT
1 stop8h 30m
Frontier
Deal found 4/20![Frontier logo]()
$134
This CheapOair deal was found by Cheapflights users on 4/20. 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 CheapOair is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 5/304:04 pm
ONT
- SEA
Nonstop3h 01m
Frontier
Sun 5/318:20 pm
SEA
- ONT
1 stop18h 49m
Frontier
Deal found 4/20![Frontier logo]()
$139
This Booking.com deal was found by Cheapflights users on 4/20. 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 Booking.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 5/3010:50 am
ONT
- SEA
1 stop23h 16m
Frontier
Sat 6/611:51 am
SEA
- ONT
Nonstop2h 44m
Frontier
Deal found 4/20![Frontier logo]()
$140
This Kiwi.com deal was found by Cheapflights users on 4/22. Clicking the “Pick Dates” 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 5/314:04 pm
ONT
- SEA
Nonstop3h 01m
Frontier
Fri 6/511:51 am
SEA
- ONT
Nonstop2h 44m
Frontier
Deal found 4/22![Frontier logo]()
$142
One-way flights from Ontario to WashingtonSearch for one-way flight options from Ontario to Washington. Find affordable one-way fares based on user searches. Data last updated April 23, 2026.
Search for one-way flight options from Ontario to Washington. Find affordable one-way fares based on user searches. Data last updated April 23, 2026.
This Super.com deal was found by Cheapflights users on 4/21. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Super.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 5/144:04 pm
ONT
- PDX
1 stop4h 47m
Frontier
Deal found 4/21![Frontier logo]()
$69
This Super.com deal was found by Cheapflights users on 4/18. 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.
Fri 5/86:00 am
ONT
- PDX
1 stop10h 46m
Frontier
Deal found 4/18![Frontier logo]()
$75
This Kiwi.com deal was found by Cheapflights users on 4/20. 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.
Wed 5/204:39 pm
ONT
- PDX
1 stop17h 41m
Frontier
Deal found 4/20![Frontier logo]()
$78
This Kiwi.com deal was found by Cheapflights users on 4/22. Clicking the “Pick Dates” 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 6/103:34 pm
ONT
- BLI
1 stop17h 40m
Multiple Airlines
Deal found 4/22![Multiple Airlines logo]()
$78
This Kiwi.com deal was found by Cheapflights users on 4/21. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 5/64:39 pm
ONT
- PDX
1 stop28h 12m
Frontier
Deal found 4/21![Frontier logo]()
$84
This Delta deal was found by Cheapflights users on 4/20. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 6/105:59 pm
ONT
- PDX
1 stop5h 55m
Delta
Deal found 4/20![Delta logo]()
$88
This Super.com deal was found by Cheapflights users on 4/21. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Super.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 5/74:04 pm
ONT
- PDX
1 stop4h 47m
Frontier
Deal found 4/21![Frontier logo]()
$89
This Frontier deal was found by Cheapflights users on 4/22. Clicking the “Pick Dates” 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 5/276:00 am
ONT
- GEG
1 stop5h 38m
Frontier
Deal found 4/22![Frontier logo]()
$90
This Trip.com deal was found by Cheapflights users on 4/20. 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.
Mon 5/1111:36 am
ONT
- PDX
1 stop8h 15m
Frontier
Deal found 4/20![Frontier logo]()
$92
This Kiwi.com deal was found by Cheapflights users on 4/21. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 6/83:30 pm
ONT
- PDX
2 stops25h 05m
Frontier
Deal found 4/21![Frontier logo]()
$93
This Frontier deal was found by Cheapflights users on 4/20. 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.
Mon 5/256:00 am
ONT
- GEG
1 stop5h 38m
Frontier
Deal found 4/20![Frontier logo]()
$95
This Super.com deal was found by Cheapflights users on 4/19. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Super.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 5/112:59 am
ONT
- PDX
1 stop10h 43m
Frontier
Deal found 4/19![Frontier logo]()
$95
Find flight deals from Ontario to Washington
Keep the following information in mind while searching for Ontario to Washington flight deals. Data was last updated April 23, 2026.
Most accurate provider | FlightHub 3 stars |
|---|---|
Most trusted provider | FlightHub 3 stars |
Round-trip from | $131 (Kiwi.com) |
One-way from | $69 (Super.com) |
Popular in | June |
Cheapest in | May |
Average price | $248 |
Good round-trip deal | $243 or less |
Good one-way deal | $158 or less |
Cheapflights Fare Finder
Customize your flight search to find flights from Ontario to Washington 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 23, 2026.
Use the filters below to find and compare flights from Ontario to Washington that are best for you.
Fly from
Fly to
Route
Depart
Return
Cheapest round-trip
OntarioSeattle
ONT - SEA
ONTSEA
Ontario
Fri 5/15
4:03 pm-6:52 pm
Nonstop2h 49m
Seattle/Tacoma Intl
Wed 5/20
8:32 am-11:12 am
Nonstop2h 40m
$207
OntarioSeattle
ONT - SEA
ONTSEA
Ontario
Sun 5/10
6:00 am-8:50 am
Nonstop2h 50m
Seattle/Tacoma Intl
Wed 5/20
8:32 am-11:12 am
Nonstop2h 40m
$207
OntarioPortland
ONT - PDX
ONTPDX
Ontario
Sat 5/30
5:55 pm-10:40 pm
1 stop4h 45m
Portland
Sun 5/31
5:30 am-11:12 am
1 stop5h 42m
$217
Quickest round-trip
OntarioPortland
ONT - PDX
ONTPDX
Ontario
Sun 5/10
7:00 am-9:24 am
Nonstop2h 24m
Portland
Sun 5/24
8:00 am-10:21 am
Nonstop2h 21m
$217
OntarioSeattle
ONT - SEA
ONTSEA
Ontario
Fri 5/15
4:03 pm-6:52 pm
Nonstop2h 49m
Seattle/Tacoma Intl
Sat 5/16
8:30 am-11:10 am
Nonstop2h 40m
$217
OntarioPortland
ONT - PDX
ONTPDX
Ontario
Fri 5/15
5:50 pm-11:55 pm
1 stop6h 05m
Portland
Mon 5/18
5:30 am-12:35 pm
1 stop7h 05m
$218
OntarioPortland
ONT - PDX
ONTPDX
Ontario
Wed 5/20
7:00 am-9:24 am
Nonstop2h 24m
Portland
Wed 5/27
7:05 am-7:08 pm
1 stop12h 03m
$250
OntarioSpokane
ONT - GEG
ONTGEG
Ontario
Wed 6/3
4:03 pm-9:18 pm
1 stop5h 15m
Spokane
Sat 6/6
6:00 am-11:10 am
1 stop5h 10m
$260
OntarioPortland
ONT - PDX
ONTPDX
Ontario
Sat 5/23
5:57 pm-8:21 pm
Nonstop2h 24m
Portland
Tue 5/26
7:05 am-7:08 pm
1 stop12h 03m
$260
OntarioPortland
ONT - PDX
ONTPDX
Ontario
Fri 5/29
3:35 pm-8:45 pm
1 stop5h 10m
Portland
Sun 5/31
8:00 am-10:21 am
Nonstop2h 21m
$267
Showing 1-10 of 60 resultsSorted by cheapest first
Best time to book a flight from Ontario to Washington
Have a flexible travel schedule? Discover the best time to fly to Washington from Ontario with our price prediction graph.
ONT-BLI
ONT-PDX
ONT-GEG
ONT-SEA
ONT-PSC
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 Washington
ONT-USWA
ONT-BLI
ONT-PDX
ONT-GEG
ONT-SEA
What is the cheapest month to book a flight from Ontario to State of Washington?
Currently, October is the cheapest month in which you can book a flight from Ontario to State of Washington (average of $37). Flying from Ontario to State of Washington in May is currently the most expensive (average of $400). 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 WA?
Find hourly flight availability from Ontario to Washington. Discover flight options and departure times throughout the day, allowing you to choose a departure time that suits your schedule. Data last updated April 23, 2026.
One of the essential ways to save on airfare from Ontario to State of Washington is to remain as flexible as possible. Flights that are in the evening tend to be the most expensive. A flight in the afternoon could potentially save you up to 9% on airfare.
What is the cheapest day to fly from Ontario to State of Washington?
Use this chart to determine the cheapest time to fly round-trip from Ontario to Washington. Price data was last updated on April 18, 2026.
Travelers seeking maximum savings on their Ontario to State of Washington flight should consider departing on Saturday afternoons when fares are most often at their lowest. Wednesday at noon flights should be avoided if possible as fares are typically the most expensive at this time.
Weekly flight availability from Ontario to State of Washington
Explore weekly flight availability from Ontario to Washington. Discover flights operating on different days of the week, giving you the flexibility to choose a travel day that best fits your plans. Compare info to find the most convenient option for your journey. Data last updated April 23, 2026.
The most flights from ONT to USWA are scheduled on a Thursday (17 on average). You will have fewer flight options on Saturday, which is when the least amount of flights are scheduled (11 on average).
How much does it cost to fly round-trip from Ontario to State of Washington?
Reviews of airlines servicing Washington
Get insights into the airlines that provide service to Washington. 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 Washington. Reviews last updated April 23, 2026.
Get a feel of what it's like to fly with Southwest,Alaska Airlines, andDelta from Ontario to Washington by reading reviews from past customers. You can also see how each airline compares in terms of entertainment options, comfort, food, crew/service, and boarding process.
Overall
8.0
Comfort
8.0
Food
7.0
Entertainment
7.5
Crew
8.6
Boarding
8.1
Reviews
1 / 20
10.0
ExcellentWilliam Drew,Nov 2025
SJC - HNL
Overall
8.0
Comfort
8.0
Food
7.0
Entertainment
7.5
Crew
8.6
Boarding
8.1
Reviews
1 / 20
10.0
ExcellentWilliam Drew,Nov 2025
SJC - HNL
Overall
8.0
Comfort
8.0
Food
7.0
Entertainment
7.5
Crew
8.6
Boarding
8.1
Reviews
1 / 20
10.0
ExcellentWilliam Drew,Nov 2025
SJC - HNL
Overall
8.0
Comfort
8.0
Food
7.0
Entertainment
7.5
Crew
8.6
Boarding
8.1
Reviews
1 / 20
10.0
ExcellentWilliam Drew,Nov 2025
SJC - HNL
Overall
8.0
Comfort
8.0
Food
7.0
Entertainment
7.5
Crew
8.6
Boarding
8.1
Reviews
1 / 20
10.0
ExcellentWilliam Drew,Nov 2025
SJC - HNL
Overall
8.0
Comfort
8.0
Food
7.0
Entertainment
7.5
Crew
8.6
Boarding
8.1
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 Washington. 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 Washington
See prices for flight routes from nearby airports that may be better suited for you.
Complete your trip
Complete your trip to Washington by adding a car rental and/or hotel reservation to your travel itinerary.
Search flights from Ontario to Washington by cabin class
Find flights from Ontario to Washington, based on your preferred cabin class, be it economy, premium economy, business, or first class.
Ontario and Washington flights
Browse other Ontario and Washington flight options. Last updated on April 23, 2026.
Popular flight searches
Check out other popular destinations found by fellow travelers in 2026
Ontario to Washington flights
Consider these flights traveling from Ontario to Washington.
Top 6 airlines flying from Ontario to Washington
Discover the top 6 airlines that operate flights from Ontario to Washington. 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 23, 2026.
| Airline | Cheapest | Average | Flexibility | On-time |
|---|---|---|---|---|
| Cheapest$86 | Average$191 | FlexibilityNo cancel fee | On-time62% | |
| Cheapest$98 | Average$284 | FlexibilityNo cancel fee | On-time85% | |
| Cheapest$99 | Average$266 | FlexibilityNo cancel fee | On-timeN/A | |
| Cheapest$139 | Average$351 | FlexibilityNo cancel fee | On-time75% | |
| Cheapest$146 | Average$310 | FlexibilityNo cancel fee | On-time63% | |
| Cheapest$258 | Average$361 | FlexibilityNo cancel fee | On-time69% |