$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 5/7. Fares are subject to change and may not be available on all flights or dates of travel.
ONT — SEA
May 18 — May 251
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 18, 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 18, 2026.
This Kiwi.com deal was found by Cheapflights users on 4/16. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 5/234:04 pm
ONT
- SEA
Nonstop3h 01m
Frontier
Sun 5/2411:51 am
SEA
- ONT
Nonstop2h 44m
Frontier
Deal found 4/16![Frontier logo]()
$126
This CheapOair deal was found by Cheapflights users on 4/15. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure 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
Thu 6/1111:53 am
SEA
- ONT
Nonstop2h 46m
Frontier
Deal found 4/15![Frontier logo]()
$128
This Super.com deal was found by Cheapflights users on 4/16. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Super.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 6/1711:53 am
SEA
- ONT
Nonstop2h 46m
Frontier
Deal found 4/16![Frontier logo]()
$132
This Frontier deal was found by Cheapflights users on 4/14. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Frontier is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 6/44:04 pm
ONT
- SEA
Nonstop3h 01m
Frontier
Tue 6/2311:53 am
SEA
- ONT
Nonstop2h 46m
Frontier
Deal found 4/14![Frontier logo]()
$133
This Expedia deal was found by Cheapflights users on 4/14. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure 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 6/88:20 pm
SEA
- ONT
1 stop18h 48m
Frontier
Deal found 4/14![Frontier logo]()
$134
This Booking.com deal was found by Cheapflights users on 4/15. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Booking.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
Sun 6/77:50 pm
SEA
- ONT
1 stop14h 15m
Frontier
Deal found 4/15![Frontier logo]()
$135
This Super.com deal was found by Cheapflights users on 4/15. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Super.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 5/234:04 pm
ONT
- SEA
Nonstop3h 01m
Frontier
Fri 5/2911:51 am
SEA
- ONT
Nonstop2h 44m
Frontier
Deal found 4/15![Frontier logo]()
$137
This Frontier deal was found by Cheapflights users on 4/14. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Frontier is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 6/164:03 pm
ONT
- SEA
Nonstop2h 54m
Frontier
Fri 6/1911:53 am
SEA
- ONT
Nonstop2h 46m
Frontier
Deal found 4/14![Frontier logo]()
$138
This Expedia deal was found by Cheapflights users on 4/14. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Expedia 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
Mon 6/88:20 pm
SEA
- ONT
1 stop23h 31m
Frontier
Deal found 4/14![Frontier logo]()
$139
This CheapOair deal was found by Cheapflights users on 4/14. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure CheapOair is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 5/510:50 am
ONT
- SEA
1 stop22h 59m
Frontier
Wed 5/67:50 pm
SEA
- ONT
1 stop14h 15m
Frontier
Deal found 4/14![Frontier logo]()
$140
This Booking.com deal was found by Cheapflights users on 4/15. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Booking.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 5/710:50 am
ONT
- SEA
1 stop22h 59m
Frontier
Mon 5/1111:37 am
SEA
- ONT
1 stop7h 55m
Frontier
Deal found 4/15![Frontier logo]()
$141
This CheapOair deal was found by Cheapflights users on 4/13. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure CheapOair is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 5/1410:50 am
ONT
- GEG
1 stop24h 48m
Frontier
Mon 5/1812:33 pm
GEG
- ONT
1 stop21h 32m
Frontier
Deal found 4/13![Frontier logo]()
$171
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 18, 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 18, 2026.
This Delta deal was found by Cheapflights users on 4/17. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 5/95:45 pm
ONT
- SEA
Nonstop3h 00m
Delta
Mon 5/119:45 am
SEA
- ONT
Nonstop2h 50m
Delta
Deal found 4/17![Delta logo]()
$207
This Alaska Airlines deal was found by Cheapflights users on 4/14. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Alaska Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 5/83:26 pm
ONT
- SEA
Nonstop2h 51m
Alaska Airlines
Sun 5/107:05 am
SEA
- ONT
Nonstop2h 40m
Alaska Airlines
Deal found 4/14![Alaska Airlines logo]()
$217
This Southwest deal was found by Cheapflights users on 4/16. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 6/161:30 pm
ONT
- PDX
1 stop6h 35m
Southwest
Sun 6/215:20 am
PDX
- ONT
1 stop5h 55m
Southwest
Deal found 4/16![Southwest logo]()
$238
This United Airlines deal was found by Cheapflights users on 4/17. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 5/86:59 pm
ONT
- SEA
1 stop6h 13m
United Airlines
Sun 5/107:08 am
SEA
- ONT
1 stop5h 14m
United Airlines
Deal found 4/17![United Airlines logo]()
$317
This Delta deal was found by Cheapflights users on 4/16. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 5/301:35 pm
ONT
- PDX
1 stop7h 43m
Delta
Mon 6/15:51 pm
PDX
- ONT
1 stop4h 41m
Delta
Deal found 4/16![Delta logo]()
$217
This Southwest deal was found by Cheapflights users on 4/16. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 6/153:40 pm
ONT
- PDX
1 stop3h 55m
Southwest
Mon 6/1510:40 pm
PDX
- ONT
1 stop8h 50m
Southwest
Deal found 4/16![Southwest logo]()
$264
This Delta deal was found by Cheapflights users on 4/14. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 6/36:45 am
ONT
- SEA
Nonstop3h 02m
Delta
Fri 6/52:30 pm
SEA
- ONT
Nonstop2h 38m
Delta
Deal found 4/14![Delta logo]()
$247
This Alaska Airlines deal was found by Cheapflights users on 4/13. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Alaska Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 8/2110:45 am
ONT
- PDX
Nonstop2h 19m
Alaska Airlines
Sun 8/237:15 am
PDX
- ONT
Nonstop2h 36m
Alaska Airlines
Deal found 4/13![Alaska Airlines logo]()
$297
This Southwest deal was found by Cheapflights users on 4/13. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 5/910:15 am
ONT
- PDX
2 stops8h 30m
Southwest
Tue 5/125:30 am
PDX
- ONT
1 stop6h 05m
Southwest
Deal found 4/13![Southwest logo]()
$277
This Alaska Airlines deal was found by Cheapflights users on 4/17. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure 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 8/235:18 am
PSC
- ONT
1 stop4h 33m
Alaska Airlines
Deal found 4/17![Alaska Airlines logo]()
$299
This United Airlines deal was found by Cheapflights users on 4/16. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 6/16:00 am
ONT
- GEG
1 stop4h 27m
United Airlines
Tue 6/306:00 am
GEG
- ONT
1 stop6h 12m
United Airlines
Deal found 4/16![United Airlines logo]()
$335
This Delta deal was found by Cheapflights users on 4/16. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 9/197:00 am
ONT
- PSC
1 stop4h 57m
Delta
Tue 9/225:45 pm
PSC
- ONT
1 stop4h 55m
Delta
Deal found 4/16![Delta logo]()
$299
This Alaska Airlines deal was found by Cheapflights users on 4/14. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Alaska Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 5/293:35 pm
ONT
- SEA
1 stop23h 49m
Alaska Airlines
Sun 5/319:22 pm
SEA
- ONT
Nonstop2h 36m
Alaska Airlines
Deal found 4/14![Alaska Airlines logo]()
$310
This Southwest deal was found by Cheapflights users on 4/13. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 5/206:30 am
ONT
- SEA
2 stops6h 55m
Southwest
Fri 5/225:00 am
SEA
- ONT
1 stop5h 25m
Southwest
Deal found 4/13![Southwest logo]()
$317
This Delta deal was found by Cheapflights users on 4/13. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 5/155:50 pm
ONT
- PSC
1 stop6h 06m
Delta
Sat 5/163:25 pm
PSC
- ONT
1 stop7h 09m
Delta
Deal found 4/13![Delta logo]()
$299
This Alaska Airlines deal was found by Cheapflights users on 4/14. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Alaska Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 5/610:39 am
ONT
- PSC
1 stop5h 03m
Alaska Airlines
Sat 5/94:19 pm
PSC
- ONT
1 stop6h 13m
Alaska Airlines
Deal found 4/14![Alaska Airlines logo]()
$316
This Southwest deal was found by Cheapflights users on 4/15. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 6/244:35 pm
ONT
- SEA
2 stops6h 55m
Southwest
Tue 6/307:30 am
SEA
- ONT
2 stops6h 35m
Southwest
Deal found 4/15![Southwest logo]()
$347
This Alaska Airlines deal was found by Cheapflights users on 4/16. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Alaska Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 5/155:57 pm
ONT
- PDX
Nonstop2h 24m
Alaska Airlines
Mon 5/188:00 am
PDX
- ONT
Nonstop2h 21m
Alaska Airlines
Deal found 4/16![Alaska Airlines logo]()
$317
This Delta deal was found by Cheapflights users on 4/15. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 8/102:00 pm
ONT
- PDX
1 stop6h 49m
Delta
Fri 8/147:14 pm
PDX
- ONT
1 stop4h 30m
Delta
Deal found 4/15![Delta logo]()
$317
This Delta deal was found by Cheapflights users on 4/15. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 7/41:48 pm
ONT
- SEA
Nonstop2h 53m
Delta
Sun 7/1210:05 am
SEA
- ONT
Nonstop2h 57m
Delta
Deal found 4/15![Delta logo]()
$317
This Southwest deal was found by Cheapflights users on 4/14. 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 Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 8/2511:10 am
ONT
- GEG
1 stop3h 55m
Southwest
Sat 8/2911:20 am
GEG
- ONT
2 stops7h 00m
Southwest
Deal found 4/14![Southwest logo]()
$357
This Alaska Airlines deal was found by Cheapflights users on 4/17. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Alaska Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 5/166:00 am
ONT
- GEG
1 stop5h 42m
Alaska Airlines
Mon 5/186:00 am
GEG
- ONT
1 stop5h 10m
Alaska Airlines
Deal found 4/17![Alaska Airlines logo]()
$333
This Delta deal was found by Cheapflights users on 4/14. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 8/217:00 am
ONT
- PSC
1 stop4h 57m
Delta
Sun 8/236:30 am
PSC
- ONT
1 stop4h 44m
Delta
Deal found 4/14![Delta logo]()
$319
This Southwest deal was found by Cheapflights users on 4/14. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 7/186:30 pm
ONT
- GEG
1 stop4h 50m
Southwest
Sat 7/256:25 am
GEG
- ONT
1 stop7h 15m
Southwest
Deal found 4/14![Southwest logo]()
$361
This Alaska Airlines deal was found by Cheapflights users on 4/17. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Alaska Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 5/277:41 pm
ONT
- ALW
1 stop4h 36m
Alaska Airlines
Sat 5/305:00 am
ALW
- ONT
1 stop6h 10m
Alaska Airlines
Deal found 4/17![Alaska Airlines logo]()
$333
This Delta deal was found by Cheapflights users on 4/14. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 5/319:50 am
ONT
- PSC
1 stop4h 16m
Delta
Tue 6/23:30 pm
PSC
- ONT
1 stop7h 02m
Delta
Deal found 4/14![Delta logo]()
$319
This Southwest deal was found by Cheapflights users on 4/17. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 5/241:45 pm
ONT
- PDX
2 stops7h 45m
Southwest
Mon 5/255:20 am
PDX
- ONT
1 stop6h 40m
Southwest
Deal found 4/17![Southwest logo]()
$367
This KAYAK deal was found by Cheapflights users on 4/13. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure KAYAK is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 5/117:59 pm
ONT
- SEA
Nonstop2h 51m
Alaska Airlines
Thu 5/149:22 pm
SEA
- ONT
Nonstop2h 36m
Alaska Airlines
Deal found 4/13![Alaska Airlines logo]()
$335
This Delta deal was found by Cheapflights users on 4/14. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 5/319:50 am
ONT
- PSC
1 stop4h 16m
Delta
Thu 6/43:30 pm
PSC
- ONT
1 stop7h 02m
Delta
Deal found 4/14![Delta logo]()
$319
This Alaska Airlines deal was found by Cheapflights users on 4/13. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Alaska Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 5/287:41 pm
ONT
- BLI
1 stop4h 26m
Alaska Airlines
Tue 6/25:53 pm
BLI
- ONT
1 stop6h 05m
Alaska Airlines
Deal found 4/13![Alaska Airlines logo]()
$336
Last-minute flights from Ontario to WashingtonDiscover last-minute flight deals from Ontario to Washington. Data last updated April 18, 2026 and is based on user searches.
Discover last-minute flight deals from Ontario to Washington. Data last updated April 18, 2026 and is based on user searches.
This Frontier deal was found by Cheapflights users on 4/16. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Frontier is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 4/2212:59 am
ONT
- SEA
1 stop8h 28m
Frontier
Mon 5/1111:37 am
SEA
- ONT
1 stop7h 55m
Frontier
Deal found 4/16![Frontier logo]()
$181
This Kiwi.com deal was found by Cheapflights users on 4/16. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 4/2212:59 am
ONT
- SEA
1 stop8h 28m
Frontier
Tue 5/127:50 pm
SEA
- ONT
1 stop14h 15m
Frontier
Deal found 4/16![Frontier logo]()
$188
This Super.com deal was found by Cheapflights users on 4/13. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Super.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 4/2512:59 am
ONT
- SEA
1 stop8h 28m
Frontier
Wed 5/67:50 pm
SEA
- ONT
1 stop14h 15m
Frontier
Deal found 4/13![Frontier logo]()
$184
This Booking.com deal was found by Cheapflights users on 4/13. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Booking.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 4/275:33 pm
ONT
- SEA
1 stop15h 54m
Frontier
Tue 4/287:12 pm
SEA
- ONT
1 stop28h 43m
Frontier
Deal found 4/13![Frontier logo]()
$182
This Expedia deal was found by Cheapflights users on 4/15. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Expedia is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 4/2812:59 am
ONT
- PDX
1 stop10h 53m
Frontier
Sat 5/212:27 pm
PDX
- ONT
1 stop11h 28m
Frontier
Deal found 4/15![Frontier logo]()
$180
This Booking.com deal was found by Cheapflights users on 4/13. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Booking.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 4/2912:59 am
ONT
- PDX
1 stop10h 04m
Frontier
Sun 5/312:45 pm
PDX
- ONT
1 stop19h 19m
Frontier
Deal found 4/13![Frontier logo]()
$182
This Travelocity deal was found by Cheapflights users on 4/15. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Travelocity is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 5/212:59 am
ONT
- GEG
1 stop9h 50m
Frontier
Fri 5/812:33 pm
GEG
- ONT
1 stop21h 32m
Frontier
Deal found 4/15![Frontier logo]()
$185
This Kiwi.com deal was found by Cheapflights users on 4/15. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 5/711:36 am
ONT
- GEG
1 stop8h 53m
Multiple Airlines
Sun 5/109:19 pm
GEG
- ONT
1 stop10h 30m
Multiple Airlines
Deal found 4/15![Multiple Airlines logo]()
$179
This Frontier deal was found by Cheapflights users on 4/15. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Frontier 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
Sun 5/109:46 pm
PDX
- ONT
1 stop10h 03m
Frontier
Deal found 4/15![Frontier logo]()
$181
This CheapOair deal was found by Cheapflights users on 4/13. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure CheapOair is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 5/1410:50 am
ONT
- GEG
1 stop24h 48m
Frontier
Mon 5/1812:33 pm
GEG
- ONT
1 stop21h 32m
Frontier
Deal found 4/13![Frontier logo]()
$171
This Booking.com deal was found by Cheapflights users on 4/16. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Booking.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 5/186:00 am
ONT
- PDX
1 stop10h 46m
Frontier
Mon 5/2511:15 am
PDX
- ONT
1 stop20h 49m
Frontier
Deal found 4/16![Frontier logo]()
$183
This Booking.com deal was found by Cheapflights users on 4/17. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Booking.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 5/3010:50 am
ONT
- PDX
1 stop5h 56m
Frontier
Mon 6/112:35 pm
PDX
- ONT
1 stop21h 30m
Frontier
Deal found 4/17![Frontier logo]()
$186
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 18, 2026.
Search for one-way flight options from Ontario to Washington. Find affordable one-way fares based on user searches. Data last updated April 18, 2026.
This Super.com deal was found by Cheapflights users on 4/16. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Super.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 5/710:50 am
ONT
- PDX
1 stop5h 56m
Frontier
Deal found 4/16![Frontier logo]()
$69
This Super.com deal was found by Cheapflights users on 4/17. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure 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 4/17![Frontier logo]()
$75
This Frontier deal was found by Cheapflights users on 4/15. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Frontier is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 5/106:00 am
ONT
- PDX
1 stop10h 46m
Frontier
Deal found 4/15![Frontier logo]()
$76
This CheapOair deal was found by Cheapflights users on 4/13. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure CheapOair 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 4/13![Frontier logo]()
$82
This Super.com deal was found by Cheapflights users on 4/14. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure 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 4/14![Frontier logo]()
$89
This Frontier deal was found by Cheapflights users on 4/17. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Frontier is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 5/226:00 am
ONT
- GEG
1 stop5h 38m
Frontier
Deal found 4/17![Frontier logo]()
$95
This Super.com deal was found by Cheapflights users on 4/14. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Super.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 4/2912:59 am
ONT
- PDX
1 stop10h 04m
Frontier
Deal found 4/14![Frontier logo]()
$95
This Frontier deal was found by Cheapflights users on 4/14. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Frontier is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 5/212:59 am
ONT
- GEG
1 stop9h 50m
Frontier
Deal found 4/14![Frontier logo]()
$96
This Frontier deal was found by Cheapflights users on 4/14. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Frontier is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 4/2712:59 am
ONT
- PDX
1 stop10h 53m
Frontier
Deal found 4/14![Frontier logo]()
$96
This Trip.com deal was found by Cheapflights users on 4/17. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Trip.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 4/2912:59 am
ONT
- GEG
1 stop9h 50m
Frontier
Deal found 4/17![Frontier logo]()
$101
This United Airlines 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 United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 5/91:30 pm
ONT
- PDX
1 stop5h 16m
United Airlines
Deal found 4/18![United Airlines logo]()
$104
This Expedia deal was found by Cheapflights users on 4/16. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Expedia is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 7/16:00 am
ONT
- GEG
1 stop5h 33m
Frontier
Deal found 4/16![Frontier logo]()
$109
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 18, 2026.
Most accurate provider | FlightHub 3 stars |
|---|---|
Most trusted provider | FlightHub 3 stars |
Round-trip from | $126 (Kiwi.com) |
One-way from | $69 (Super.com) |
Popular in | June |
Cheapest in | May |
Average price | $240 |
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 18, 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
Sat 5/9
5:45 pm-8:45 pm
Nonstop3h 00m
Seattle/Tacoma Intl
Mon 5/11
9:45 am-12:35 pm
Nonstop2h 50m
$207
OntarioSeattle
ONT - SEA
ONTSEA
Ontario
Fri 5/8
3:26 pm-6:17 pm
Nonstop2h 51m
Seattle/Tacoma Intl
Sun 5/10
7:05 am-9:45 am
Nonstop2h 40m
$217
OntarioPortland
ONT - PDX
ONTPDX
Ontario
Sat 5/30
1:35 pm-9:18 pm
1 stop7h 43m
Portland
Mon 6/1
5:51 pm-10:32 pm
1 stop4h 41m
$217
OntarioPortland
ONT - PDX
ONTPDX
Ontario
Tue 6/16
1:30 pm-8:05 pm
1 stop6h 35m
Portland
Sun 6/21
5:20 am-11:15 am
1 stop5h 55m
$238
OntarioSeattle
ONT - SEA
ONTSEA
Ontario
Wed 6/3
6:45 am-9:47 am
Nonstop3h 02m
Seattle/Tacoma Intl
Fri 6/5
2:30 pm-5:08 pm
Nonstop2h 38m
$247
OntarioPortland
ONT - PDX
ONTPDX
Ontario
Mon 6/15
3:40 pm-7:35 pm
1 stop3h 55m
Portland
Mon 6/15
10:40 pm-7:30 am
1 stop8h 50m
$264
OntarioPortland
ONT - PDX
ONTPDX
Ontario
Sat 5/9
10:15 am-6:45 pm
2 stops8h 30m
Portland
Tue 5/12
5:30 am-11:35 am
1 stop6h 05m
$277
OntarioPortland
ONT - PDX
ONTPDX
Ontario
Fri 8/21
10:45 am-1:04 pm
Nonstop2h 19m
Portland
Sun 8/23
7:15 am-9:51 am
Nonstop2h 36m
$297
OntarioPasco
ONT - PSC
ONTPSC
Ontario
Fri 8/21
7:57 pm-10:12 am
1 stop14h 15m
Pasco Tri Cities
Sun 8/23
5:18 am-9:51 am
1 stop4h 33m
$299
OntarioPasco
ONT - PSC
ONTPSC
Ontario
Sat 9/19
7:00 am-11:57 am
1 stop4h 57m
Pasco Tri Cities
Tue 9/22
5:45 pm-10:40 pm
1 stop4h 55m
$299
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-SEA
ONT-PDX
ONT-PSC
ONT-GEG
ONT-ALW
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-SEA
ONT-PDX
ONT-PSC
ONT-GEG
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 18, 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 18, 2026.
The most flights from ONT to USWA are scheduled on a Friday (20 on average). You will have fewer flight options on Tuesday, which is when the least amount of flights are scheduled (10 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 18, 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
Overall
8.0
Comfort
8.0
Food
7.0
Boarding
8.1
Entertainment
7.5
Reviews
1 / 20
10.0
ExcellentWilliam Drew,Nov 2025
SJC - HNL
Crew
8.6
Overall
8.0
Comfort
8.0
Food
7.0
Boarding
8.1
Entertainment
7.5
Reviews
1 / 20
10.0
ExcellentWilliam Drew,Nov 2025
SJC - HNL
Crew
8.6
Overall
8.0
Comfort
8.0
Food
7.0
Boarding
8.1
Entertainment
7.5
Reviews
1 / 20
10.0
ExcellentWilliam Drew,Nov 2025
SJC - HNL
Crew
8.6
Overall
8.0
Comfort
8.0
Food
7.0
Boarding
8.1
Entertainment
7.5
Reviews
1 / 20
10.0
ExcellentWilliam Drew,Nov 2025
SJC - HNL
Crew
8.6
Overall
8.0
Comfort
8.0
Food
7.0
Boarding
8.1
Entertainment
7.5
Reviews
1 / 20
10.0
ExcellentWilliam Drew,Nov 2025
SJC - HNL
Crew
8.6
Overall
8.0
Comfort
8.0
Food
7.0
Boarding
8.1
Entertainment
7.5
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
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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 April 18, 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 18, 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% |