$84+ Cheap flights from Ontario (ONT) to Dulles Intl (IAD)
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 7/14. Fares are subject to change and may not be available on all flights or dates of travel.
ONT — IAD
Jul 11 — Jul 181
Round-trip
1 adult, Economy
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Find cheap flights from Ontario to Dulles Intl with Cheapflights
1. Tell us where you want to go
Enter your travel information like dates, passengers, trip type (one-way or round trip), and preferred cabin class then click “Find deals”2. Select your favorite providers
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Review each provider’s pricing and select the best option for you! Book through your favorite provider’s website for a seamless experience.Cheap flight deals from Ontario to Dulles Intl
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Cheapest flights from Ontario to Dulles IntlExplore the most affordable flight options available from Ontario to Dulles Intl. Find the lowest fares from popular airlines and budget airlines, with prices last updated on June 11, 2026.
Explore the most affordable flight options available from Ontario to Dulles Intl. Find the lowest fares from popular airlines and budget airlines, with prices last updated on June 11, 2026.
This CheapOair deal was found by Cheapflights users on 6/6. Clicking the “Pick Dates” 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 7/13:34 pm
ONT
- IAD
1 stop13h 51m
Frontier
Sat 7/49:35 am
IAD
- ONT
1 stop13h 16m
Frontier
Deal found 6/6![Frontier logo]()
$252
This Trip.com deal was found by Cheapflights users on 6/10. Clicking the “Pick Dates” 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.
Tue 7/141:38 pm
ONT
- IAD
1 stop15h 42m
Frontier
Mon 7/209:50 am
IAD
- ONT
1 stop9h 04m
Frontier
Deal found 6/10![Frontier logo]()
$268
This United Airlines deal was found by Cheapflights users on 6/9. Clicking the “Pick Dates” 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 9/97:00 am
ONT
- IAD
1 stop7h 37m
United Airlines
Wed 9/231:10 pm
IAD
- ONT
1 stop9h 47m
United Airlines
Deal found 6/9![United Airlines logo]()
$270
This Delta deal was found by Cheapflights users on 6/10. Clicking the “Pick Dates” 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 9/912:00 pm
ONT
- IAD
1 stop9h 10m
Delta
Wed 9/166:00 am
IAD
- ONT
1 stop7h 47m
Delta
Deal found 6/10![Delta logo]()
$280
This Delta deal was found by Cheapflights users on 6/8. Clicking the “Pick Dates” 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 8/1410:00 pm
ONT
- IAD
1 stop9h 04m
Delta
Thu 8/203:03 pm
IAD
- ONT
1 stop9h 49m
Delta
Deal found 6/8![Delta logo]()
$282
This Kiwi.com deal was found by Cheapflights users on 6/9. Clicking the “Pick Dates” 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 7/158:17 am
ONT
- IAD
2 stops11h 38m
Frontier
Mon 7/209:50 am
IAD
- ONT
1 stop25h 13m
Frontier
Deal found 6/9![Frontier logo]()
$290
This Expedia deal was found by Cheapflights users on 6/8. Clicking the “Pick Dates” 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 7/293:40 pm
ONT
- IAD
1 stop13h 40m
Multiple Airlines
Wed 8/126:03 am
IAD
- ONT
1 stop10h 06m
Multiple Airlines
Deal found 6/8![Multiple Airlines logo]()
$292
This Frontier deal was found by Cheapflights users on 6/8. Clicking the “Pick Dates” 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 8/193:34 pm
ONT
- IAD
1 stop13h 16m
Frontier
Wed 8/269:20 am
IAD
- ONT
1 stop13h 28m
Frontier
Deal found 6/8![Frontier logo]()
$295
This Frontier deal was found by Cheapflights users on 6/8. Clicking the “Pick Dates” 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 7/73:40 pm
ONT
- IAD
1 stop13h 40m
Frontier
Sat 7/119:30 am
IAD
- ONT
1 stop8h 44m
Frontier
Deal found 6/8![Frontier logo]()
$296
This Kissandfly.com deal was found by Cheapflights users on 6/8. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kissandfly.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 8/311:52 am
ONT
- IAD
1 stop17h 28m
Frontier
Wed 8/129:50 am
IAD
- ONT
1 stop8h 24m
Frontier
Deal found 6/8![Frontier logo]()
$300
This Frontier deal was found by Cheapflights users on 6/8. Clicking the “Pick Dates” 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 8/203:34 pm
ONT
- IAD
1 stop13h 16m
Frontier
Sat 8/299:20 am
IAD
- ONT
1 stop8h 49m
Frontier
Deal found 6/8![Frontier logo]()
$301
This Frontier deal was found by Cheapflights users on 6/6. Clicking the “Pick Dates” 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 7/83:40 pm
ONT
- IAD
1 stop13h 40m
Frontier
Mon 7/139:50 am
IAD
- ONT
1 stop9h 04m
Frontier
Deal found 6/6![Frontier logo]()
$302
Best flights from Ontario to Dulles IntlDiscover carefully curated flight deals from Ontario to Dulles Intl that have cost, travel time, and layovers in mind to ensure you get the best travel experience. Data last updated June 11, 2026.
Discover carefully curated flight deals from Ontario to Dulles Intl that have cost, travel time, and layovers in mind to ensure you get the best travel experience. Data last updated June 11, 2026.
This Alaska Airlines deal was found by Cheapflights users on 6/10. Clicking the “Pick Dates” 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 9/93:14 pm
ONT
- IAD
1 stop11h 26m
Alaska Airlines
Tue 9/157:00 am
IAD
- ONT
1 stop10h 16m
Alaska Airlines
Deal found 6/10![Alaska Airlines logo]()
$331
This United Airlines deal was found by Cheapflights users on 6/9. Clicking the “Pick Dates” 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 11/181:00 pm
ONT
- IAD
1 stop7h 13m
United Airlines
Wed 11/256:30 am
IAD
- ONT
1 stop8h 50m
United Airlines
Deal found 6/9![United Airlines logo]()
$340
This Delta deal was found by Cheapflights users on 6/10. Clicking the “Pick Dates” 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 8/1412:00 pm
ONT
- IAD
1 stop9h 34m
Delta
Sun 8/167:00 am
IAD
- ONT
1 stop8h 16m
Delta
Deal found 6/10![Delta logo]()
$347
This Delta deal was found by Cheapflights users on 6/10. Clicking the “Pick Dates” 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 10/1812:00 pm
ONT
- IAD
1 stop9h 20m
Delta
Mon 11/25:30 pm
IAD
- ONT
1 stop7h 44m
Delta
Deal found 6/10![Delta logo]()
$360
This Delta deal was found by Cheapflights users on 6/8. Clicking the “Pick Dates” 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 8/261:06 pm
ONT
- IAD
1 stop7h 33m
Delta
Sun 8/307:00 am
IAD
- ONT
1 stop8h 16m
Delta
Deal found 6/8![Delta logo]()
$361
This United Airlines deal was found by Cheapflights users on 6/10. Clicking the “Pick Dates” 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 9/17:00 am
ONT
- IAD
1 stop7h 37m
United Airlines
Wed 9/26:42 am
IAD
- ONT
1 stop8h 30m
United Airlines
Deal found 6/10![United Airlines logo]()
$415
This Alaska Airlines deal was found by Cheapflights users on 6/7. Clicking the “Pick Dates” 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 10/216:00 am
ONT
- IAD
2 stops13h 47m
Alaska Airlines
Tue 10/279:35 am
IAD
- ONT
1 stop11h 25m
Alaska Airlines
Deal found 6/7![Alaska Airlines logo]()
$436
This Alaska Airlines deal was found by Cheapflights users on 6/9. Clicking the “Pick Dates” 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 9/63:07 pm
ONT
- IAD
1 stop11h 33m
Alaska Airlines
Fri 9/115:57 pm
IAD
- ONT
1 stop20h 19m
Alaska Airlines
Deal found 6/9![Alaska Airlines logo]()
$450
This Alaska Airlines deal was found by Cheapflights users on 6/6. Clicking the “Pick Dates” 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 9/43:07 pm
ONT
- IAD
1 stop11h 33m
Alaska Airlines
Mon 9/75:47 pm
IAD
- ONT
1 stop20h 29m
Alaska Airlines
Deal found 6/6![Alaska Airlines logo]()
$471
This Alaska Airlines deal was found by Cheapflights users on 6/8. Clicking the “Pick Dates” 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 11/64:09 pm
ONT
- IAD
1 stop10h 42m
Alaska Airlines
Wed 11/117:46 am
IAD
- ONT
1 stop10h 29m
Alaska Airlines
Deal found 6/8![Alaska Airlines logo]()
$481
Last-minute flights from Ontario to Dulles IntlDiscover last-minute flight deals from Ontario to Dulles Intl. Data last updated June 11, 2026 and is based on user searches.
Discover last-minute flight deals from Ontario to Dulles Intl. Data last updated June 11, 2026 and is based on user searches.
This CheapOair deal was found by Cheapflights users on 6/6. Clicking the “Pick Dates” 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 7/13:34 pm
ONT
- IAD
1 stop13h 51m
Frontier
Sat 7/49:35 am
IAD
- ONT
1 stop13h 16m
Frontier
Deal found 6/6![Frontier logo]()
$252
This Frontier deal was found by Cheapflights users on 6/8. Clicking the “Pick Dates” 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 7/73:40 pm
ONT
- IAD
1 stop13h 40m
Frontier
Sat 7/119:30 am
IAD
- ONT
1 stop8h 44m
Frontier
Deal found 6/8![Frontier logo]()
$296
This Frontier deal was found by Cheapflights users on 6/6. Clicking the “Pick Dates” 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 7/83:40 pm
ONT
- IAD
1 stop13h 40m
Frontier
Mon 7/139:50 am
IAD
- ONT
1 stop9h 04m
Frontier
Deal found 6/6![Frontier logo]()
$302
This Booking.com deal was found by Cheapflights users on 6/10. Clicking the “Pick Dates” 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.
Fri 7/103:40 pm
ONT
- IAD
1 stop13h 40m
Frontier
Sun 7/199:50 am
IAD
- ONT
1 stop25h 13m
Frontier
Deal found 6/10![Frontier logo]()
$310
This Kiwi.com deal was found by Cheapflights users on 6/9. Clicking the “Pick Dates” 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 7/139:32 am
ONT
- IAD
2 stops28h 08m
Frontier
Mon 7/209:50 am
IAD
- ONT
1 stop25h 13m
Frontier
Deal found 6/9![Frontier logo]()
$311
This Trip.com deal was found by Cheapflights users on 6/10. Clicking the “Pick Dates” 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.
Tue 7/141:38 pm
ONT
- IAD
1 stop15h 42m
Frontier
Mon 7/209:50 am
IAD
- ONT
1 stop9h 04m
Frontier
Deal found 6/10![Frontier logo]()
$268
This Kiwi.com deal was found by Cheapflights users on 6/9. Clicking the “Pick Dates” 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 7/158:17 am
ONT
- IAD
2 stops11h 38m
Frontier
Mon 7/209:50 am
IAD
- ONT
1 stop25h 13m
Frontier
Deal found 6/9![Frontier logo]()
$290
This Frontier deal was found by Cheapflights users on 6/10. Clicking the “Pick Dates” 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 7/203:40 pm
ONT
- IAD
1 stop13h 40m
Frontier
Tue 7/289:50 am
IAD
- ONT
1 stop8h 24m
Frontier
Deal found 6/10![Frontier logo]()
$307
This Frontier deal was found by Cheapflights users on 6/9. Clicking the “Pick Dates” 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 7/273:40 pm
ONT
- IAD
1 stop13h 40m
Frontier
Fri 8/79:50 am
IAD
- ONT
1 stop9h 04m
Frontier
Deal found 6/9![Frontier logo]()
$301
This Frontier deal was found by Cheapflights users on 6/9. Clicking the “Pick Dates” 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 7/283:40 pm
ONT
- IAD
1 stop13h 40m
Frontier
Tue 8/49:38 pm
IAD
- ONT
1 stop14h 03m
Frontier
Deal found 6/9![Frontier logo]()
$295
This Booking.com deal was found by Cheapflights users on 6/7. Clicking the “Pick Dates” 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 7/281:38 pm
ONT
- IAD
1 stop15h 42m
Frontier
Sun 8/99:50 am
IAD
- ONT
1 stop25h 13m
Frontier
Deal found 6/7![Frontier logo]()
$309
This Expedia deal was found by Cheapflights users on 6/8. Clicking the “Pick Dates” 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 7/293:40 pm
ONT
- IAD
1 stop13h 40m
Multiple Airlines
Wed 8/126:03 am
IAD
- ONT
1 stop10h 06m
Multiple Airlines
Deal found 6/8![Multiple Airlines logo]()
$292
One-way flights from Ontario to Dulles IntlSearch for one-way flight options from Ontario to Dulles Intl. Find affordable one-way fares based on user searches. Data last updated June 11, 2026.
Search for one-way flight options from Ontario to Dulles Intl. Find affordable one-way fares based on user searches. Data last updated June 11, 2026.
This Trip.com deal was found by Cheapflights users on 6/10. Clicking the “Pick Dates” 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.
Tue 7/141:38 pm
ONT
- IAD
1 stop15h 42m
Frontier
Deal found 6/10![Frontier logo]()
$84
This Trip.com deal was found by Cheapflights users on 6/11. Clicking the “Pick Dates” 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 8/125:08 pm
ONT
- IAD
1 stop12h 12m
Frontier
Deal found 6/11![Frontier logo]()
$96
This Trip.com deal was found by Cheapflights users on 6/10. Clicking the “Pick Dates” 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 8/193:34 pm
ONT
- IAD
1 stop13h 16m
Frontier
Deal found 6/10![Frontier logo]()
$97
This Trip.com deal was found by Cheapflights users on 6/10. Clicking the “Pick Dates” 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 7/83:40 pm
ONT
- IAD
1 stop13h 40m
Frontier
Deal found 6/10![Frontier logo]()
$104
This Trip.com deal was found by Cheapflights users on 6/9. Clicking the “Pick Dates” 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.
Tue 7/283:40 pm
ONT
- IAD
1 stop13h 40m
Frontier
Deal found 6/9![Frontier logo]()
$114
This Trip.com deal was found by Cheapflights users on 6/10. Clicking the “Pick Dates” 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 7/293:40 pm
ONT
- IAD
1 stop13h 40m
Frontier
Deal found 6/10![Frontier logo]()
$115
This Frontier deal was found by Cheapflights users on 6/11. Clicking the “Pick Dates” 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 8/158:17 am
ONT
- IAD
1 stop9h 55m
Frontier
Deal found 6/11![Frontier logo]()
$120
This Trip.com deal was found by Cheapflights users on 6/10. Clicking the “Pick Dates” 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.
Thu 8/134:34 pm
ONT
- IAD
1 stop12h 46m
Frontier
Deal found 6/10![Frontier logo]()
$122
This Trip.com deal was found by Cheapflights users on 6/9. Clicking the “Pick Dates” 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.
Thu 8/273:34 pm
ONT
- IAD
1 stop13h 16m
Frontier
Deal found 6/9![Frontier logo]()
$123
Find flight deals from Ontario to Dulles Intl
Discover tips and strategies to find the most affordable flight options for your journey from Ontario (ONT) to Dulles Intl (IAD). Learn about various techniques such as flexible date searches, comparing prices across and setting up price alerts. Use these methods to find the cheapest flights available for your travel needs. Data last updated June 11, 2026.
Most accurate provider | FlightHub 3 stars |
|---|---|
Most trusted provider | FlightHub 3 stars |
Round-trip from | $268 (Trip.com) |
One-way from | $84 (Trip.com) |
Popular in | April |
Cheapest in | September |
Average price | $513 |
Cheapflights Fare Finder
Customize your flight search to find flights from Ontario to Dulles Intl 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 June 11, 2026.
Use the filters below to find and compare flights from Ontario to Washington, D.C. Dulles Intl Airport that are best for you.
Fly from
Fly to
Route
Depart
Return
Cheapest round-trip
OntarioWashington, D.C.
ONT - IAD
ONTIAD
Ontario
Wed 9/9
3:14 pm-5:40 am
1 stop11h 26m
Washington, D.C. Dulles Intl
Tue 9/15
7:00 am-2:16 pm
1 stop10h 16m
$331
OntarioWashington, D.C.
ONT - IAD
ONTIAD
Ontario
Wed 11/18
1:00 pm-11:13 pm
1 stop7h 13m
Washington, D.C. Dulles Intl
Wed 11/25
6:30 am-12:20 pm
1 stop8h 50m
$340
OntarioWashington, D.C.
ONT - IAD
ONTIAD
Ontario
Fri 8/14
12:00 pm-12:34 am
1 stop9h 34m
Washington, D.C. Dulles Intl
Sun 8/16
7:00 am-12:16 pm
1 stop8h 16m
$347
OntarioWashington, D.C.
ONT - IAD
ONTIAD
Ontario
Sun 10/18
12:00 pm-12:20 am
1 stop9h 20m
Washington, D.C. Dulles Intl
Mon 11/2
5:30 pm-10:14 pm
1 stop7h 44m
$360
Quickest round-trip
OntarioWashington, D.C.
ONT - IAD
ONTIAD
Ontario
Wed 8/26
1:06 pm-11:39 pm
1 stop7h 33m
Washington, D.C. Dulles Intl
Sun 8/30
7:00 am-12:16 pm
1 stop8h 16m
$361
OntarioWashington, D.C.
ONT - IAD
ONTIAD
Ontario
Tue 9/1
7:00 am-5:37 pm
1 stop7h 37m
Washington, D.C. Dulles Intl
Wed 9/2
6:42 am-12:12 pm
1 stop8h 30m
$415
OntarioWashington, D.C.
ONT - IAD
ONTIAD
Ontario
Wed 10/21
6:00 am-10:47 pm
2 stops13h 47m
Washington, D.C. Dulles Intl
Tue 10/27
9:35 am-6:00 pm
1 stop11h 25m
$436
OntarioWashington, D.C.
ONT - IAD
ONTIAD
Ontario
Sun 9/6
3:07 pm-5:40 am
1 stop11h 33m
Washington, D.C. Dulles Intl
Fri 9/11
5:57 pm-11:16 am
1 stop20h 19m
$450
OntarioWashington, D.C.
ONT - IAD
ONTIAD
Ontario
Fri 9/4
3:07 pm-5:40 am
1 stop11h 33m
Washington, D.C. Dulles Intl
Mon 9/7
5:47 pm-11:16 am
1 stop20h 29m
$471
OntarioWashington, D.C.
ONT - IAD
ONTIAD
Ontario
Fri 11/6
4:09 pm-5:51 am
1 stop10h 42m
Washington, D.C. Dulles Intl
Wed 11/11
7:46 am-3:15 pm
1 stop10h 29m
$481
Showing 1-10 of 22 resultsSorted by cheapest first
Compare providers for flights from Ontario to Dulles Intl
Provider information is updated monthly. Please note that these providers often have deals for this flight, but the availability may vary on a day-by-day basis on Cheapflights.
Use the table below to compare price accuracy, trust ratings, and cancellation policies for each provider offering flight deals from Ontario to Dulles Intl in June.
| Provider | Price Accuracy | Trust Score* |
|---|---|---|
| Price Accuracy1 star | Trust Score*3 stars | |
| Price Accuracy3 stars | Trust Score*3 stars | |
| Price Accuracy3 stars | Trust Score*3 stars |
- Most accurate provider: When it comes to deals on Ontario-Washington, D.C. Dulles Intl Airport flights, users find the pricing of FlightHub to be most consistent on Cheapflights vs. FlightHub Users can find the same prices on Ontario-Washington, D.C. Dulles Intl Airport flight deals on Cheapflights vs. FlightHub >95% of the time. Price accuracy is based on data collected from Ontario-Washington, D.C. Dulles Intl Airport flight searches over the past month and is updated monthly.
- Most trusted provider: When it comes to deals on Ontario-Washington, D.C. Dulles Intl Airport flights, Cheapflights users trust FlightHub the most. FlightHub has received a user feedback score of 3 out of 3 stars (3 being the best), meaning they have been trusted the most by Cheapflights users looking for Ontario-Washington, D.C. Dulles Intl Airport flight deals. Provider user feedback score is based on Cheapflights searches over the past month and is updated monthly.
Best time to book a flight from Ontario to Dulles Intl
Have a flexible travel schedule? Discover the best time to fly to Dulles Intl from Ontario with our price prediction graph.
ONT-IAD
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, D.C. Dulles Intl Airport
What is the cheapest month to book a flight from Ontario to Washington, D.C. Dulles Intl Airport?
Currently, September is the cheapest month in which you can book a flight from Ontario to Washington, D.C. Dulles Intl Airport (average of $270). Flying from Ontario to Washington, D.C. Dulles Intl Airport in April is currently the most expensive (average of $908). 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.
How much does it cost to fly round-trip from Ontario to Washington, D.C. Dulles Intl Airport?
Reviews of airlines servicing Dulles Intl
Get insights into the airlines that provide service to Dulles Intl. 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 Dulles Intl. Reviews last updated June 11, 2026.
Read reviews from past customers who have flown Southwest,Delta, andUnited Airlines from Ontario to Washington, D.C. Dulles Intl Airport. Users can see the overall rating for each airline as well as how each is rated in terms of entertainment options, comfort, food, crew/service, and boarding process.
Food
7.0
Entertainment
7.5
Boarding
8.1
Crew
8.6
Comfort
8.0
Overall
7.9
Reviews
1 / 20
8.0
ExcellentLa Tracimeldamarcos,Jun 2026
LAX - SLC
Food
7.0
Entertainment
7.5
Boarding
8.1
Crew
8.6
Comfort
8.0
Overall
7.9
Reviews
1 / 20
8.0
ExcellentLa Tracimeldamarcos,Jun 2026
LAX - SLC
Food
7.0
Entertainment
7.5
Boarding
8.1
Crew
8.6
Comfort
8.0
Overall
7.9
Reviews
1 / 20
8.0
ExcellentLa Tracimeldamarcos,Jun 2026
LAX - SLC
Food
7.0
Entertainment
7.5
Boarding
8.1
Crew
8.6
Comfort
8.0
Overall
7.9
Reviews
1 / 20
8.0
ExcellentLa Tracimeldamarcos,Jun 2026
LAX - SLC
Food
7.0
Entertainment
7.5
Boarding
8.1
Crew
8.6
Comfort
8.0
Overall
7.9
Reviews
1 / 20
8.0
ExcellentLa Tracimeldamarcos,Jun 2026
LAX - SLC
Food
7.0
Entertainment
7.5
Boarding
8.1
Crew
8.6
Comfort
8.0
Overall
7.9
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 Dulles Intl. Access travel guides, tips, and recommendations to enhance your travel experience. Get information about local attractions, weather, transportation options, and more.
Traveling to a place near Washington, D.C. Dulles Intl Airport?
Book flights to Washington, D.C. Dulles Intl Airport if you plan to visit one of these locationsAlexandria
Tysons
Owings Mills
Springfield
Arlington
Reston
Rockville
Herndon
Fredericksburg
Laurel
Hyattsville
Manassas
Hanover
Chantilly
Lanham
Falls Church
Waldorf
Silver Spring
Largo
Clinton
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Other flights to Dulles Intl
Explore flights to Dulles Intl departing from other origins. Flights are based on user searches made on Cheapflights and were last updated on June 11, 2026.
Search flights from Ontario to Dulles Intl by cabin class
Find flights from Ontario to Dulles Intl, based on your preferred cabin class, be it economy, premium economy, business, or first class.
Ontario and Dulles Intl flights
Browse other Ontario and Dulles Intl flight options. Last updated on June 11, 2026.
Other flights from Ontario
Browse through other flights departing from Ontario. Flights are based on user searches made on Cheapflights and were last updated on June 11, 2026.
Popular flight searches
Check out other popular destinations found by fellow travelers in 2026
Top 5 airlines flying from Ontario to Dulles Intl
Discover the top 5 airlines that operate flights from Ontario to Dulles Intl. 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 June 11, 2026.
| Airline | Cheapest | Average | Flexibility | On-time |
|---|---|---|---|---|
| Cheapest$172 | Average$452 | FlexibilityNo cancel fee | On-timeN/A | |
| Cheapest$192 | Average$295 | FlexibilityNo cancel fee | On-time62% | |
| Cheapest$256 | Average$559 | FlexibilityNo cancel fee | On-time71% | |
| Cheapest$297 | Average$611 | FlexibilityNo cancel fee | On-time69% | |
| Cheapest$298 | Average$448 | FlexibilityNo cancel fee | On-time63% |