$90+ 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 10/17. Fares are subject to change and may not be available on all flights or dates of travel.
ONT — SEA
Aug 19 — Aug 261
Round-trip
1 adult, Economy
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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 July 20, 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 July 20, 2026.
This Kiwi.com deal was found by Cheapflights users on 7/17. 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.
Fri 8/285:17 pm
ONT
- SEA
Nonstop2h 45m
Frontier
Sun 8/309:29 pm
SEA
- ONT
1 stop10h 34m
Frontier
Deal found 7/17![Frontier logo]()
$222
This Frontier deal was found by Cheapflights users on 7/15. 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.
Wed 9/24:49 pm
ONT
- SEA
Nonstop2h 49m
Frontier
Sun 9/611:54 am
SEA
- ONT
Nonstop2h 51m
Frontier
Deal found 7/15![Frontier logo]()
$223
This Kiwi.com deal was found by Cheapflights users on 7/18. 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.
Fri 8/74:49 pm
ONT
- SEA
Nonstop2h 49m
Frontier
Mon 8/319:29 pm
SEA
- ONT
1 stop18h 25m
Frontier
Deal found 7/18![Frontier logo]()
$224
This Super.com deal was found by Cheapflights users on 7/19. 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.
Sun 8/166:00 am
ONT
- SEA
1 stop7h 17m
Frontier
Sat 8/2211:54 am
SEA
- ONT
Nonstop2h 51m
Frontier
Deal found 7/19![Frontier logo]()
$225
This Kiwi.com deal was found by Cheapflights users on 7/15. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 8/134:49 pm
ONT
- SEA
Nonstop2h 49m
Frontier
Tue 8/188:53 pm
SEA
- ONT
2 stops17h 10m
Frontier
Deal found 7/15![Frontier logo]()
$226
This Priceline deal was found by Cheapflights users on 7/15. 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 Priceline is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 9/257:12 am
ONT
- SEA
1 stop5h 38m
Multiple Airlines
Sun 9/2711:15 am
SEA
- ONT
Nonstop2h 48m
Multiple Airlines
Deal found 7/15![Multiple Airlines logo]()
$227
This Frontier deal was found by Cheapflights users on 7/19. 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.
Sat 9/54:49 pm
ONT
- SEA
Nonstop2h 49m
Frontier
Mon 9/1411:15 am
SEA
- ONT
Nonstop2h 48m
Frontier
Deal found 7/19![Frontier logo]()
$228
This Frontier deal was found by Cheapflights users on 7/16. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Frontier is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 9/105:05 pm
ONT
- SEA
Nonstop2h 56m
Frontier
Mon 9/1411:15 am
SEA
- ONT
Nonstop2h 48m
Frontier
Deal found 7/16![Frontier logo]()
$229
This Super.com deal was found by Cheapflights users on 7/18. 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.
Mon 8/174:49 pm
ONT
- SEA
Nonstop2h 49m
Frontier
Mon 8/2411:54 am
SEA
- ONT
Nonstop2h 51m
Frontier
Deal found 7/18![Frontier logo]()
$231
This Frontier deal was found by Cheapflights users on 7/19. 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.
Sat 9/56:00 am
ONT
- SEA
1 stop7h 22m
Frontier
Sun 9/1311:15 am
SEA
- ONT
Nonstop2h 48m
Frontier
Deal found 7/19![Frontier logo]()
$232
This Southwest deal was found by Cheapflights users on 7/15. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 8/142:40 pm
ONT
- PDX
1 stop4h 35m
Southwest
Sun 8/167:00 am
PDX
- ONT
1 stop6h 25m
Southwest
Deal found 7/15![Southwest logo]()
$242
This Southwest deal was found by Cheapflights users on 7/15. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 8/214:10 pm
ONT
- PDX
1 stop6h 00m
Southwest
Sun 8/237:00 am
PDX
- ONT
1 stop6h 25m
Southwest
Deal found 7/15![Southwest logo]()
$247
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 July 20, 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 July 20, 2026.
This Delta deal was found by Cheapflights users on 7/15. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 9/255:15 pm
ONT
- PDX
1 stop6h 25m
Delta
Sun 9/277:15 pm
PDX
- ONT
1 stop4h 32m
Delta
Deal found 7/15![Delta logo]()
$247
This Southwest deal was found by Cheapflights users on 7/19. 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 8/2710:55 am
ONT
- PDX
1 stop3h 50m
Southwest
Mon 8/315:00 am
PDX
- ONT
2 stops8h 25m
Southwest
Deal found 7/19![Southwest logo]()
$252
This Alaska Airlines deal was found by Cheapflights users on 7/15. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Alaska Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 8/266:05 pm
ONT
- SEA
1 stop4h 34m
Alaska Airlines
Tue 9/110:41 am
SEA
- ONT
1 stop5h 06m
Alaska Airlines
Deal found 7/15![Alaska Airlines logo]()
$257
This Kiwi.com deal was found by Cheapflights users on 7/14. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 8/104:09 pm
ONT
- BLI
1 stop5h 45m
Multiple Airlines
Sun 8/161:28 pm
BLI
- ONT
1 stop18h 35m
Multiple Airlines
Deal found 7/14![Multiple Airlines logo]()
$296
This United Airlines deal was found by Cheapflights users on 7/17. 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.
Wed 8/55:00 am
ONT
- GEG
1 stop7h 37m
United Airlines
Sat 8/86:00 am
GEG
- ONT
1 stop6h 12m
United Airlines
Deal found 7/17![United Airlines logo]()
$349
This Delta deal was found by Cheapflights users on 7/15. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 8/293:35 pm
ONT
- PDX
1 stop7h 03m
Delta
Mon 8/3112:25 pm
PDX
- ONT
1 stop4h 56m
Delta
Deal found 7/15![Delta logo]()
$247
This Alaska Airlines deal was found by Cheapflights users on 7/19. 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.
Sat 9/197:12 am
ONT
- PDX
Nonstop2h 18m
Alaska Airlines
Wed 9/235:07 am
PDX
- ONT
1 stop6h 09m
Alaska Airlines
Deal found 7/19![Alaska Airlines logo]()
$267
This Southwest deal was found by Cheapflights users on 7/17. 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.
Sat 10/37:35 am
ONT
- SEA
1 stop4h 35m
Southwest
Mon 10/56:55 am
SEA
- ONT
1 stop5h 05m
Southwest
Deal found 7/17![Southwest logo]()
$267
This Alaska Airlines deal was found by Cheapflights users on 7/16. 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.
Wed 9/237:12 am
ONT
- SEA
1 stop5h 38m
Alaska Airlines
Fri 9/2512:30 pm
SEA
- ONT
1 stop4h 48m
Alaska Airlines
Deal found 7/16![Alaska Airlines logo]()
$267
This Southwest deal was found by Cheapflights users on 7/17. 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.
Mon 9/2812:35 pm
ONT
- SEA
1 stop6h 10m
Southwest
Wed 9/308:30 am
SEA
- ONT
2 stops7h 35m
Southwest
Deal found 7/17![Southwest logo]()
$272
This Delta deal was found by Cheapflights users on 7/17. 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.
Mon 8/109:43 am
ONT
- PDX
1 stop6h 20m
Delta
Fri 8/143:25 pm
PDX
- ONT
1 stop7h 20m
Delta
Deal found 7/17![Delta logo]()
$273
This Southwest deal was found by Cheapflights users on 7/17. 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.
Sat 8/1511:00 am
ONT
- PDX
2 stops7h 20m
Southwest
Sat 8/226:20 am
PDX
- ONT
2 stops7h 55m
Southwest
Deal found 7/17![Southwest logo]()
$287
This Alaska Airlines deal was found by Cheapflights users on 7/19. 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 8/193:07 pm
ONT
- PDX
1 stop4h 43m
Alaska Airlines
Sun 8/237:18 am
PDX
- ONT
Nonstop2h 33m
Alaska Airlines
Deal found 7/19![Alaska Airlines logo]()
$287
This Delta deal was found by Cheapflights users on 7/16. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 10/36:00 pm
ONT
- SEA
Nonstop2h 50m
Delta
Mon 10/511:22 am
SEA
- ONT
1 stop5h 13m
Delta
Deal found 7/16![Delta logo]()
$287
This Kiwi.com deal was found by Cheapflights users on 7/14. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 8/74:09 pm
ONT
- BLI
1 stop5h 45m
Multiple Airlines
Sun 8/161:28 pm
BLI
- ONT
1 stop18h 35m
Multiple Airlines
Deal found 7/14![Multiple Airlines logo]()
$364
This Southwest deal was found by Cheapflights users on 7/17. 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.
Tue 8/189:40 am
ONT
- PDX
2 stops5h 45m
Southwest
Tue 8/256:35 am
PDX
- ONT
2 stops6h 05m
Southwest
Deal found 7/17![Southwest logo]()
$287
This Alaska Airlines deal was found by Cheapflights users on 7/19. 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 11/45:12 pm
ONT
- SEA
1 stop4h 18m
Alaska Airlines
Fri 11/2010:54 am
SEA
- ONT
1 stop5h 46m
Alaska Airlines
Deal found 7/19![Alaska Airlines logo]()
$292
This Delta deal was found by Cheapflights users on 7/18. 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 9/196:00 pm
ONT
- PSC
1 stop4h 44m
Delta
Tue 9/225:23 pm
PSC
- ONT
1 stop6h 24m
Delta
Deal found 7/18![Delta logo]()
$311
This Alaska Airlines deal was found by Cheapflights users on 7/17. 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.
Sat 8/810:54 am
ONT
- PDX
Nonstop2h 15m
Alaska Airlines
Sun 8/97:36 am
PDX
- ONT
Nonstop2h 20m
Alaska Airlines
Deal found 7/17![Alaska Airlines logo]()
$297
This Southwest deal was found by Cheapflights users on 7/16. 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.
Sat 9/2611:00 am
ONT
- SEA
2 stops8h 30m
Southwest
Mon 9/286:15 am
SEA
- ONT
1 stop7h 10m
Southwest
Deal found 7/16![Southwest logo]()
$302
This Kiwi.com deal was found by Cheapflights users on 7/14. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 8/111:52 am
ONT
- BLI
1 stop22h 47m
Multiple Airlines
Fri 8/73:52 pm
BLI
- ONT
1 stop16h 11m
Multiple Airlines
Deal found 7/14![Multiple Airlines logo]()
$414
This Delta deal was found by Cheapflights users on 7/16. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 8/106:01 pm
ONT
- GEG
1 stop5h 58m
Delta
Thu 8/134:20 pm
GEG
- ONT
1 stop6h 25m
Delta
Deal found 7/16![Delta logo]()
$333
This Southwest deal was found by Cheapflights users on 7/16. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 10/512:40 pm
ONT
- SEA
2 stops9h 50m
Southwest
Wed 10/712:05 pm
SEA
- ONT
2 stops7h 30m
Southwest
Deal found 7/16![Southwest logo]()
$307
This Alaska Airlines deal was found by Cheapflights users on 7/15. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Alaska Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 8/104:18 pm
ONT
- SEA
1 stop5h 03m
Alaska Airlines
Fri 8/213:50 pm
SEA
- ONT
1 stop4h 34m
Alaska Airlines
Deal found 7/15![Alaska Airlines logo]()
$312
This Delta deal was found by Cheapflights users on 7/16. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 8/125:05 pm
ONT
- GEG
1 stop6h 21m
Delta
Thu 8/137:15 pm
GEG
- ONT
1 stop4h 19m
Delta
Deal found 7/16![Delta logo]()
$333
This Southwest deal was found by Cheapflights users on 7/16. 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.
Thu 7/308:45 pm
ONT
- PDX
1 stop4h 40m
Southwest
Tue 8/46:35 am
PDX
- ONT
2 stops6h 05m
Southwest
Deal found 7/16![Southwest logo]()
$308
This Alaska Airlines deal was found by Cheapflights users on 7/19. 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.
Tue 9/154:27 pm
ONT
- SEA
2 stops6h 12m
Alaska Airlines
Tue 9/2210:37 am
SEA
- ONT
1 stop5h 10m
Alaska Airlines
Deal found 7/19![Alaska Airlines logo]()
$315
This Delta deal was found by Cheapflights users on 7/15. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 8/225:05 pm
ONT
- GEG
1 stop5h 26m
Delta
Mon 8/244:20 pm
GEG
- ONT
1 stop6h 25m
Delta
Deal found 7/15![Delta logo]()
$333
This Southwest deal was found by Cheapflights users on 7/17. 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.
Thu 10/17:05 pm
ONT
- PDX
1 stop4h 40m
Southwest
Mon 10/55:30 am
PDX
- ONT
2 stops8h 30m
Southwest
Deal found 7/17![Southwest logo]()
$316
This Alaska Airlines deal was found by Cheapflights users on 7/15. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Alaska Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 11/1110:37 am
ONT
- PDX
Nonstop2h 23m
Alaska Airlines
Sun 11/157:05 am
PDX
- ONT
1 stop8h 10m
Alaska Airlines
Deal found 7/15![Alaska Airlines logo]()
$317
Last-minute flights from Ontario to WashingtonDiscover last-minute flight deals from Ontario to Washington. Data last updated July 20, 2026 and is based on user searches.
Discover last-minute flight deals from Ontario to Washington. Data last updated July 20, 2026 and is based on user searches.
This Kiwi.com deal was found by Cheapflights users on 7/15. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 8/56:00 am
ONT
- SEA
1 stop27h 04m
Frontier
Mon 8/108:53 pm
SEA
- ONT
1 stop11h 10m
Frontier
Deal found 7/15![Frontier logo]()
$223
This Kiwi.com deal was found by Cheapflights users on 7/18. 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.
Fri 8/74:49 pm
ONT
- SEA
Nonstop2h 49m
Frontier
Mon 8/319:29 pm
SEA
- ONT
1 stop18h 25m
Frontier
Deal found 7/18![Frontier logo]()
$224
This Kiwi.com deal was found by Cheapflights users on 7/17. 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.
Tue 8/118:58 am
ONT
- SEA
2 stops26h 06m
Frontier
Sat 8/158:13 pm
SEA
- ONT
1 stop11h 50m
Frontier
Deal found 7/17![Frontier logo]()
$232
This Kiwi.com deal was found by Cheapflights users on 7/15. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 8/134:49 pm
ONT
- SEA
Nonstop2h 49m
Frontier
Tue 8/188:53 pm
SEA
- ONT
2 stops17h 10m
Frontier
Deal found 7/15![Frontier logo]()
$226
This Super.com deal was found by Cheapflights users on 7/15. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Super.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 8/136:00 am
ONT
- SEA
1 stop7h 17m
Frontier
Mon 8/1712:19 pm
SEA
- ONT
Nonstop2h 55m
Frontier
Deal found 7/15![Frontier logo]()
$230
This Super.com deal was found by Cheapflights users on 7/19. 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 8/1410:49 am
ONT
- SEA
1 stop26h 28m
Frontier
Tue 8/2511:54 am
SEA
- ONT
Nonstop2h 51m
Frontier
Deal found 7/19![Frontier logo]()
$229
This Super.com deal was found by Cheapflights users on 7/19. 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.
Sun 8/166:00 am
ONT
- SEA
1 stop7h 17m
Frontier
Sat 8/2211:54 am
SEA
- ONT
Nonstop2h 51m
Frontier
Deal found 7/19![Frontier logo]()
$225
This Frontier deal was found by Cheapflights users on 7/18. 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.
Sun 8/166:00 am
ONT
- SEA
1 stop7h 17m
Frontier
Wed 8/1911:54 am
SEA
- ONT
Nonstop2h 51m
Frontier
Deal found 7/18![Frontier logo]()
$228
This Super.com deal was found by Cheapflights users on 7/18. 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.
Mon 8/174:49 pm
ONT
- SEA
Nonstop2h 49m
Frontier
Mon 8/2411:54 am
SEA
- ONT
Nonstop2h 51m
Frontier
Deal found 7/18![Frontier logo]()
$231
This Frontier deal was found by Cheapflights users on 7/16. 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.
Mon 8/174:49 pm
ONT
- SEA
Nonstop2h 49m
Frontier
Fri 8/2111:54 am
SEA
- ONT
Nonstop2h 51m
Frontier
Deal found 7/16![Frontier logo]()
$233
This CheapOair deal was found by Cheapflights users on 7/15. 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 CheapOair is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 8/224:49 pm
ONT
- SEA
Nonstop2h 49m
Frontier
Mon 8/3111:54 am
SEA
- ONT
Nonstop2h 51m
Frontier
Deal found 7/15![Frontier logo]()
$227
This Kiwi.com deal was found by Cheapflights users on 7/17. 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.
Fri 8/285:17 pm
ONT
- SEA
Nonstop2h 45m
Frontier
Sun 8/309:29 pm
SEA
- ONT
1 stop10h 34m
Frontier
Deal found 7/17![Frontier logo]()
$222
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 July 20, 2026.
Search for one-way flight options from Ontario to Washington. Find affordable one-way fares based on user searches. Data last updated July 20, 2026.
This Kiwi.com deal was found by Cheapflights users on 7/15. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 10/176:00 am
ONT
- PDX
1 stop10h 35m
Frontier
Deal found 7/15![Frontier logo]()
$90
This Super.com deal was found by Cheapflights users on 7/16. 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 Super.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 8/54:09 pm
ONT
- SEA
Nonstop2h 49m
Frontier
Deal found 7/16![Frontier logo]()
$103
This Kiwi.com deal was found by Cheapflights users on 7/16. 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.
Thu 10/159:12 pm
ONT
- SEA
1 stop12h 48m
Frontier
Deal found 7/16![Frontier logo]()
$105
This Kiwi.com deal was found by Cheapflights users on 7/16. 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.
Thu 8/64:49 pm
ONT
- SEA
Nonstop2h 49m
Frontier
Deal found 7/16![Frontier logo]()
$106
This Kiwi.com deal was found by Cheapflights users on 7/16. 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.
Tue 9/156:00 am
ONT
- PDX
1 stop8h 27m
Frontier
Deal found 7/16![Frontier logo]()
$107
This Kiwi.com deal was found by Cheapflights users on 7/16. 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.
Sat 9/126:00 am
ONT
- PDX
1 stop10h 35m
Frontier
Deal found 7/16![Frontier logo]()
$108
This Super.com deal was found by Cheapflights users on 7/15. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Super.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 9/54:49 pm
ONT
- SEA
Nonstop2h 49m
Frontier
Deal found 7/15![Frontier logo]()
$108
This United Airlines deal was found by Cheapflights users on 7/19. 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.
Tue 9/19:01 am
ONT
- SEA
1 stop5h 23m
United Airlines
Deal found 7/19![United Airlines logo]()
$109
This Kiwi.com deal was found by Cheapflights users on 7/15. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 9/1111:16 am
ONT
- SEA
1 stop22h 44m
Frontier
Deal found 7/15![Frontier logo]()
$110
This Super.com deal was found by Cheapflights users on 7/15. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Super.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 9/95:05 pm
ONT
- SEA
Nonstop2h 56m
Frontier
Deal found 7/15![Frontier logo]()
$111
This Kiwi.com deal was found by Cheapflights users on 7/17. 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.
Tue 10/136:00 am
ONT
- PDX
1 stop10h 35m
Frontier
Deal found 7/17![Frontier logo]()
$112
This Super.com deal was found by Cheapflights users on 7/16. 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 Super.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 9/175:05 pm
ONT
- SEA
Nonstop2h 56m
Frontier
Deal found 7/16![Frontier logo]()
$112
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 July 20, 2026.
Most accurate provider | FlightHub 3 stars |
|---|---|
Most trusted provider | FlightHub 3 stars |
Round-trip from | $222 (Kiwi.com) |
One-way from | $90 (Kiwi.com) |
Popular in | June |
Cheapest in | March |
Average price | $307 |
Good round-trip deal | $291 or less |
Good one-way deal | $193 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 July 20, 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
OntarioPortland
ONT - PDX
ONTPDX
Ontario
Fri 9/25
5:15 pm-11:40 pm
1 stop6h 25m
Portland
Sun 9/27
7:15 pm-11:47 pm
1 stop4h 32m
$247
OntarioPortland
ONT - PDX
ONTPDX
Ontario
Sat 8/29
3:35 pm-10:38 pm
1 stop7h 03m
Portland
Mon 8/31
12:25 pm-5:21 pm
1 stop4h 56m
$247
OntarioPortland
ONT - PDX
ONTPDX
Ontario
Thu 8/27
10:55 am-2:45 pm
1 stop3h 50m
Portland
Mon 8/31
5:00 am-1:25 pm
2 stops8h 25m
$252
OntarioSeattle
ONT - SEA
ONTSEA
Ontario
Wed 8/26
6:05 pm-10:39 pm
1 stop4h 34m
Seattle/Tacoma Intl
Tue 9/1
10:41 am-3:47 pm
1 stop5h 06m
$257
OntarioPortland
ONT - PDX
ONTPDX
Ontario
Sat 9/19
7:12 am-9:30 am
Nonstop2h 18m
Portland
Wed 9/23
5:07 am-11:16 am
1 stop6h 09m
$267
OntarioSeattle
ONT - SEA
ONTSEA
Ontario
Sat 10/3
7:35 am-12:10 pm
1 stop4h 35m
Seattle/Tacoma Intl
Mon 10/5
6:55 am-12:00 pm
1 stop5h 05m
$267
OntarioSeattle
ONT - SEA
ONTSEA
Ontario
Wed 9/23
7:12 am-12:50 pm
1 stop5h 38m
Seattle/Tacoma Intl
Fri 9/25
12:30 pm-5:18 pm
1 stop4h 48m
$267
OntarioSeattle
ONT - SEA
ONTSEA
Ontario
Mon 9/28
12:35 pm-6:45 pm
1 stop6h 10m
Seattle/Tacoma Intl
Wed 9/30
8:30 am-4:05 pm
2 stops7h 35m
$272
OntarioPortland
ONT - PDX
ONTPDX
Ontario
Mon 8/10
9:43 am-4:03 pm
1 stop6h 20m
Portland
Fri 8/14
3:25 pm-10:45 pm
1 stop7h 20m
$273
OntarioPortland
ONT - PDX
ONTPDX
Ontario
Sat 8/15
11:00 am-6:20 pm
2 stops7h 20m
Portland
Sat 8/22
6:20 am-2:15 pm
2 stops7h 55m
$287
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-PDX
ONT-SEA
ONT-BLI
ONT-GEG
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-PDX
ONT-SEA
ONT-BLI
ONT-GEG
What is the cheapest month to book a flight from Ontario to State of Washington?
Currently, January is the cheapest month in which you can book a flight from Ontario to State of Washington (average of $216). Flying from Ontario to State of Washington in July is currently the most expensive (average of $326). 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 July 20, 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 at noon tend to be the most expensive. A flight in the afternoon could potentially save you up to 17% on airfare.
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 July 20, 2026.
The most flights from ONT to USWA are scheduled on a Sunday (27 on average). You will have fewer flight options on Wednesday, which is when the least amount of flights are scheduled (15 on average).
How much does it cost to fly round-trip from Ontario to State of Washington?
How far ahead should I book a flight from Ontario to State of Washington?
Booking 55 days in advance of your planned departure date is, on average, the best time to get cheap flights from Ontario to State of Washington. 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 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 July 18, 2026.
Travelers seeking maximum savings on their Ontario to State of Washington flight should consider departing on Sunday afternoons when fares are most often at their lowest. Saturday evenings flights should be avoided if possible as fares are typically the most expensive at this time.
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 July 20, 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.
Crew
8.6
Boarding
8.1
Entertainment
7.5
Food
7.0
Comfort
8.0
Overall
8.0
Reviews
1 / 20
8.0
ExcellentLa Tracimeldamarcos,Jun 2026
LAX - SLC
Crew
8.6
Boarding
8.1
Entertainment
7.5
Food
7.0
Comfort
8.0
Overall
8.0
Reviews
1 / 20
8.0
ExcellentLa Tracimeldamarcos,Jun 2026
LAX - SLC
Crew
8.6
Boarding
8.1
Entertainment
7.5
Food
7.0
Comfort
8.0
Overall
8.0
Reviews
1 / 20
8.0
ExcellentLa Tracimeldamarcos,Jun 2026
LAX - SLC
Crew
8.6
Boarding
8.1
Entertainment
7.5
Food
7.0
Comfort
8.0
Overall
8.0
Reviews
1 / 20
8.0
ExcellentLa Tracimeldamarcos,Jun 2026
LAX - SLC
Crew
8.6
Boarding
8.1
Entertainment
7.5
Food
7.0
Comfort
8.0
Overall
8.0
Reviews
1 / 20
8.0
ExcellentLa Tracimeldamarcos,Jun 2026
LAX - SLC
Crew
8.6
Boarding
8.1
Entertainment
7.5
Food
7.0
Comfort
8.0
Overall
8.0
Reviews
1 / 20
8.0
ExcellentLa Tracimeldamarcos,Jun 2026
LAX - SLC
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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Toggle through the tabs below to find thousands of options on Cheapflights for your next trip.
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Alternative routes for Ontario to Washington
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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 July 20, 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 July 20, 2026.
| Airline | Cheapest | Average | Flexibility | On-time |
|---|---|---|---|---|
| Cheapest$85 | Average$223 | FlexibilityNo cancel fee | On-time62% | |
| Cheapest$88 | Average$209 | FlexibilityNo cancel fee | On-time85% | |
| Cheapest$101 | Average$316 | FlexibilityNo cancel fee | On-timeN/A | |
| Cheapest$139 | Average$423 | FlexibilityNo cancel fee | On-time75% | |
| Cheapest$150 | Average$339 | FlexibilityNo cancel fee | On-time63% | |
| Cheapest$272 | Average$361 | FlexibilityNo cancel fee | On-time69% |