$124+ Cheap flights from Ontario (ONT) to Dulles Intl (IAD)
This is the cheapest round-trip flight price found by a Cheapflights user in the last 72 hours by searching for a flight departing on 10/8. Fares are subject to change and may not be available on all flights or dates of travel.
ONT — IAD
Oct 8 — Oct 151
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
We find the providers serving your travel needs. Choose up to four travel providers to compare side-by-side for flights, hotels, or car rentals.3. Compare prices and book
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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Best
Last-minute
One-way
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 September 8, 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 September 8, 2026.
This CheapOair deal was found by Cheapflights users on 9/3. Clicking the “Pick Dates” 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 10/17:46 pm -
1 stop12h 47m
Mon 10/56:00 am -
1 stop8h 22m
Deal found 9/3![Frontier logo]()
$267
This Trip.com deal was found by Cheapflights users on 9/4. Clicking the “Pick Dates” 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 10/17:46 pm -
1 stop12h 47m
Tue 10/66:00 am -
1 stop13h 59m
Deal found 9/4![Frontier logo]()
$275
This Frontier deal was found by Cheapflights users on 9/3. Clicking the “Pick Dates” 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 9/258:24 pm -
1 stop6h 56m
Thu 10/112:30 pm -
1 stop9h 09m
Deal found 9/3![Frontier logo]()
$277
This Frontier deal was found by Cheapflights users on 9/3. Clicking the “Pick Dates” 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 10/32:30 pm -
1 stop12h 50m
Mon 10/56:00 am -
1 stop8h 22m
Deal found 9/3![Frontier logo]()
$287
This CheapOair deal was found by Cheapflights users on 9/3. Clicking the “Pick Dates” 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 10/2011:26 am -
1 stop15h 54m
Fri 10/2312:30 pm -
1 stop9h 38m
Deal found 9/3![Frontier logo]()
$292
This Frontier deal was found by Cheapflights users on 9/3. Clicking the “Pick Dates” 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 9/258:24 pm -
1 stop6h 56m
Fri 10/212:30 pm -
1 stop9h 09m
Deal found 9/3![Frontier logo]()
$302
This Frontier deal was found by Cheapflights users on 9/3. Clicking the “Pick Dates” 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 11/68:03 pm -
1 stop12h 33m
Thu 11/1212:31 pm -
1 stop9h 37m
Deal found 9/3![Frontier logo]()
$304
This Priceline deal was found by Cheapflights users on 9/3. Clicking the “Pick Dates” 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.
Mon 10/198:35 pm -
1 stop6h 45m
Tue 10/277:02 am -
1 stop9h 14m
Deal found 9/3![Multiple Airlines logo]()
$307
This Frontier deal was found by Cheapflights users on 9/3. Clicking the “Pick Dates” 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 9/258:24 pm -
1 stop6h 56m
Sat 9/2612:30 pm -
1 stop7h 16m
Deal found 9/3![Frontier logo]()
$312
This Kiwi.com deal was found by Cheapflights users on 9/3. Clicking the “Pick Dates” 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 10/128:35 pm -
2 stops24h 46m
Wed 10/146:00 am -
1 stop7h 31m
Deal found 9/3![Frontier logo]()
$315
This Kiwi.com deal was found by Cheapflights users on 9/6. 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 10/65:44 pm -
1 stop9h 36m
Tue 10/136:00 am -
1 stop13h 30m
Deal found 9/6![Frontier logo]()
$318
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 September 8, 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 September 8, 2026.
This Alaska Airlines deal was found by Cheapflights users on 9/5. Clicking the “Pick Dates” 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 10/2711:13 am -
1 stop9h 46m
Sat 10/317:02 am -
1 stop9h 14m
Deal found 9/5![Alaska Airlines logo]()
$351
This Delta deal was found by Cheapflights users on 9/7. 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 Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 12/161:11 pm -
1 stop7h 36m
Thu 1/76:40 am -
1 stop7h 47m
Deal found 9/7![Delta logo]()
$351
This Alaska Airlines deal was found by Cheapflights users on 9/7. 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 10/2111:13 am -
1 stop9h 46m
Tue 10/277:02 am -
1 stop9h 14m
Deal found 9/7![Alaska Airlines logo]()
$351
This Alaska Airlines deal was found by Cheapflights users on 9/5. Clicking the “Pick Dates” 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 9/3012:12 pm -
1 stop8h 47m
Tue 10/67:02 am -
1 stop9h 14m
Deal found 9/5![Alaska Airlines logo]()
$351
This Delta deal was found by Cheapflights users on 9/4. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 10/296:00 am -
2 stops13h 49m
Sat 11/1411:10 am -
2 stops14h 50m
Deal found 9/4![Delta logo]()
$393
This Delta deal was found by Cheapflights users on 9/4. Clicking the “Pick Dates” 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 10/286:20 am -
2 stops14h 15m
Sat 11/1411:25 am -
2 stops14h 35m
Deal found 9/4![Delta logo]()
$393
This Alaska Airlines deal was found by Cheapflights users on 9/5. Clicking the “Pick Dates” 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 10/262:13 pm -
1 stop12h 27m
Sat 10/317:02 am -
1 stop9h 14m
Deal found 9/5![Alaska Airlines logo]()
$367
This Delta deal was found by Cheapflights users on 9/5. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 10/11:04 pm -
1 stop7h 39m
Tue 10/66:00 am -
1 stop8h 06m
Deal found 9/5![Delta logo]()
$396
This Alaska Airlines deal was found by Cheapflights users on 9/6. 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.
Wed 9/303:14 pm -
1 stop11h 26m
Sat 10/37:02 am -
1 stop30h 15m
Deal found 9/6![Alaska Airlines logo]()
$367
This Delta deal was found by Cheapflights users on 9/5. Clicking the “Pick Dates” 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 9/307:05 am -
1 stop7h 06m
Sun 10/46:00 am -
1 stop8h 09m
Deal found 9/5![Delta logo]()
$401
This Alaska Airlines deal was found by Cheapflights users on 9/3. Clicking the “Pick Dates” 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 10/2411:13 am -
1 stop9h 46m
Tue 10/277:02 am -
1 stop9h 14m
Deal found 9/3![Alaska Airlines logo]()
$376
Last-minute flights from Ontario to Dulles IntlDiscover last-minute flight deals from Ontario to Dulles Intl. Data last updated September 8, 2026 and is based on user searches.
Discover last-minute flight deals from Ontario to Dulles Intl. Data last updated September 8, 2026 and is based on user searches.
This Frontier deal was found by Cheapflights users on 9/3. Clicking the “Pick Dates” 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 9/252:30 pm -
1 stop12h 50m
Thu 10/112:30 pm -
1 stop9h 09m
Deal found 9/3![Frontier logo]()
$277
This Frontier deal was found by Cheapflights users on 9/3. Clicking the “Pick Dates” 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 9/258:24 pm -
1 stop6h 56m
Fri 10/212:30 pm -
1 stop9h 09m
Deal found 9/3![Frontier logo]()
$302
This Frontier deal was found by Cheapflights users on 9/3. Clicking the “Pick Dates” 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 9/258:24 pm -
1 stop6h 56m
Sat 9/2612:30 pm -
1 stop7h 16m
Deal found 9/3![Frontier logo]()
$312
This CheapOair deal was found by Cheapflights users on 9/3. Clicking the “Pick Dates” 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 10/17:46 pm -
1 stop12h 47m
Mon 10/56:00 am -
1 stop8h 22m
Deal found 9/3![Frontier logo]()
$267
This Trip.com deal was found by Cheapflights users on 9/4. Clicking the “Pick Dates” 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 10/17:46 pm -
1 stop12h 47m
Tue 10/66:00 am -
1 stop13h 59m
Deal found 9/4![Frontier logo]()
$275
This Frontier deal was found by Cheapflights users on 9/3. Clicking the “Pick Dates” 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 10/32:30 pm -
1 stop12h 50m
Mon 10/56:00 am -
1 stop8h 22m
Deal found 9/3![Frontier logo]()
$287
This Kiwi.com deal was found by Cheapflights users on 9/6. 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 10/65:44 pm -
1 stop9h 36m
Tue 10/136:00 am -
1 stop13h 30m
Deal found 9/6![Frontier logo]()
$318
This Kiwi.com deal was found by Cheapflights users on 9/3. Clicking the “Pick Dates” 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 10/128:35 pm -
2 stops24h 46m
Wed 10/146:00 am -
1 stop7h 31m
Deal found 9/3![Frontier logo]()
$315
This Kiwi.com deal was found by Cheapflights users on 9/6. 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 10/1411:26 am -
1 stop15h 54m
Wed 10/216:00 am -
1 stop13h 30m
Deal found 9/6![Frontier logo]()
$304
This Priceline deal was found by Cheapflights users on 9/3. Clicking the “Pick Dates” 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.
Mon 10/198:35 pm -
1 stop6h 45m
Tue 10/277:02 am -
1 stop9h 14m
Deal found 9/3![Multiple Airlines logo]()
$307
This CheapOair deal was found by Cheapflights users on 9/3. Clicking the “Pick Dates” 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 10/2011:26 am -
1 stop15h 54m
Fri 10/2312:30 pm -
1 stop9h 38m
Deal found 9/3![Frontier 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 September 8, 2026.
Search for one-way flight options from Ontario to Dulles Intl. Find affordable one-way fares based on user searches. Data last updated September 8, 2026.
This Super.com deal was found by Cheapflights users on 9/3. Clicking the “Pick Dates” 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 10/88:35 pm -
1 stop6h 45m
Wed 12/3112:00 am -
Nonstop0h 00m
Deal found 9/3![Frontier logo]()
$124
This Super.com deal was found by Cheapflights users on 9/3. Clicking the “Pick Dates” 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.
Tue 9/295:44 pm -
1 stop9h 36m
Wed 12/3112:00 am -
Nonstop0h 00m
Deal found 9/3![Frontier logo]()
$125
This Frontier deal was found by Cheapflights users on 9/3. Clicking the “Pick Dates” 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 10/268:35 pm -
1 stop6h 45m
Wed 12/3112:00 am -
Nonstop0h 00m
Deal found 9/3![Frontier logo]()
$126
This Booking.com deal was found by Cheapflights users on 9/3. Clicking the “Pick Dates” 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 10/198:35 pm -
1 stop6h 45m
Wed 12/3112:00 am -
Nonstop0h 00m
Deal found 9/3![Frontier logo]()
$127
This Super.com deal was found by Cheapflights users on 9/3. Clicking the “Pick Dates” 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 11/28:03 pm -
1 stop12h 33m
Wed 12/3112:00 am -
Nonstop0h 00m
Deal found 9/3![Frontier logo]()
$130
This Frontier deal was found by Cheapflights users on 9/3. Clicking the “Pick Dates” 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 11/128:03 pm -
1 stop12h 33m
Wed 12/3112:00 am -
Nonstop0h 00m
Deal found 9/3![Frontier logo]()
$132
This Super.com deal was found by Cheapflights users on 9/3. Clicking the “Pick Dates” 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 10/28:24 pm -
1 stop6h 56m
Wed 12/3112:00 am -
Nonstop0h 00m
Deal found 9/3![Frontier logo]()
$149
This Super.com deal was found by Cheapflights users on 9/3. Clicking the “Pick Dates” 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 10/308:03 pm -
1 stop12h 33m
Wed 12/3112:00 am -
Nonstop0h 00m
Deal found 9/3![Frontier logo]()
$154
This Super.com deal was found by Cheapflights users on 9/3. Clicking the “Pick Dates” 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 11/98:03 pm -
1 stop12h 33m
Wed 12/3112:00 am -
Nonstop0h 00m
Deal found 9/3![Frontier logo]()
$162
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 September 8, 2026.
Most accurate provider | FlightHub 3 stars |
|---|---|
Most trusted provider | FlightHub 3 stars |
Round-trip from | $267 (CheapOair) |
One-way from | $124 (Super.com) |
Popular in | April |
Cheapest in | September |
Average price | $375 |
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 7,457,451 searches. Data last updated September 8, 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 Ontario - IAD Washington, D.C. Dulles Intl
ONTIAD
Ontario
Wed 2/17
4:00 pm-5:31 am
1 stop10h 31m
Washington, D.C. Dulles Intl
Wed 12/31
12:00 am-9:00 pm
Nonstop0h 00m
$176
OntarioWashington, D.C.
ONT Ontario - IAD Washington, D.C. Dulles Intl
ONTIAD
Ontario
Sat 10/24
4:03 pm-5:46 am
1 stop10h 43m
Washington, D.C. Dulles Intl
Wed 12/31
12:00 am-9:00 pm
Nonstop0h 00m
$176
OntarioWashington, D.C.
ONT Ontario - IAD Washington, D.C. Dulles Intl
ONTIAD
Ontario
Tue 10/20
11:13 am-11:59 pm
1 stop9h 46m
Washington, D.C. Dulles Intl
Wed 12/31
12:00 am-9:00 pm
Nonstop0h 00m
$176
OntarioWashington, D.C.
ONT Ontario - IAD Washington, D.C. Dulles Intl
ONTIAD
Ontario
Tue 11/3
4:09 pm-5:44 am
1 stop10h 35m
Washington, D.C. Dulles Intl
Wed 12/31
12:00 am-9:00 pm
Nonstop0h 00m
$176
OntarioWashington, D.C.
ONT Ontario - IAD Washington, D.C. Dulles Intl
ONTIAD
Ontario
Tue 12/29
7:05 am-7:00 pm
1 stop8h 55m
Washington, D.C. Dulles Intl
Wed 12/31
12:00 am-9:00 pm
Nonstop0h 00m
$186
OntarioWashington, D.C.
ONT Ontario - IAD Washington, D.C. Dulles Intl
ONTIAD
Ontario
Mon 9/28
10:00 pm-9:09 am
1 stop8h 09m
Washington, D.C. Dulles Intl
Wed 12/31
12:00 am-9:00 pm
Nonstop0h 00m
$202
OntarioWashington, D.C.
ONT Ontario - IAD Washington, D.C. Dulles Intl
ONTIAD
Ontario
Wed 10/7
7:07 am-5:10 pm
1 stop7h 03m
Washington, D.C. Dulles Intl
Wed 12/31
12:00 am-9:00 pm
Nonstop0h 00m
$211
Quickest round-trip
OntarioWashington, D.C.
ONT Ontario - IAD Washington, D.C. Dulles Intl
ONTIAD
Ontario
Sat 10/3
10:25 am-8:24 pm
1 stop6h 59m
Washington, D.C. Dulles Intl
Wed 12/31
12:00 am-9:00 pm
Nonstop0h 00m
$231
OntarioWashington, D.C.
ONT Ontario - IAD Washington, D.C. Dulles Intl
ONTIAD
Ontario
Wed 2/3
7:00 am-5:23 pm
1 stop7h 23m
Washington, D.C. Dulles Intl
Wed 12/31
12:00 am-9:00 pm
Nonstop0h 00m
$231
OntarioWashington, D.C.
ONT Ontario - IAD Washington, D.C. Dulles Intl
ONTIAD
Ontario
Mon 2/22
1:33 pm-1:17 am
1 stop8h 44m
Washington, D.C. Dulles Intl
Wed 12/31
12:00 am-9:00 pm
Nonstop0h 00m
$231
Showing 1-10 of 23 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 September.
| 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 $375). Flying from Ontario to Washington, D.C. Dulles Intl Airport in April is currently the most expensive (average of $984). 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?
Airfare is below average for this route at the moment.
Ontario to Washington, D.C. Dulles Intl Airport flights typically cost between $350 and $620 in October.The cheapest round-trip price found within the last 5 days was $267 on Frontier (Oct 16-Oct 19).
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 September 8, 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.
Overall
8.0
Comfort
8.0
Entertainment
7.5
Boarding
8.1
Crew
8.6
Food
7.0
Reviews
1 / 20
8.0
ExcellentLa Tracimeldamarcos,Jun 2026
LAX - SLC
Overall
8.0
Comfort
8.0
Entertainment
7.5
Boarding
8.1
Crew
8.6
Food
7.0
Reviews
1 / 20
8.0
ExcellentLa Tracimeldamarcos,Jun 2026
LAX - SLC
Overall
8.0
Comfort
8.0
Entertainment
7.5
Boarding
8.1
Crew
8.6
Food
7.0
Reviews
1 / 20
8.0
ExcellentLa Tracimeldamarcos,Jun 2026
LAX - SLC
Overall
8.0
Comfort
8.0
Entertainment
7.5
Boarding
8.1
Crew
8.6
Food
7.0
Reviews
1 / 20
8.0
ExcellentLa Tracimeldamarcos,Jun 2026
LAX - SLC
Overall
8.0
Comfort
8.0
Entertainment
7.5
Boarding
8.1
Crew
8.6
Food
7.0
Reviews
1 / 20
8.0
ExcellentLa Tracimeldamarcos,Jun 2026
LAX - SLC
Overall
8.0
Comfort
8.0
Entertainment
7.5
Boarding
8.1
Crew
8.6
Food
7.0
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 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
Arlington
Owings Mills
Tysons
Lanham
Reston
Chantilly
Herndon
Rockville
Hyattsville
Fredericksburg
Woodbridge
Falls Church
Sterling
Hanover
Laurel
Oxon Hill
Clinton
Hunt Valley
Silver Spring
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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 September 8, 2026.
Search flights from Ontario to Dulles Intl by cabin class
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Ontario and Dulles Intl flights
Browse other Ontario and Dulles Intl flight options. Last updated on September 8, 2026.
Other flights from Ontario
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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 7,457,451 searches. Data last updated September 8, 2026.
| Airline | Cheapest | Average | Flexibility | On-time |
|---|---|---|---|---|
| Cheapest$192 | Average$318 | FlexibilityNo cancel fee | On-time62% | |
| Cheapest$318 | Average$448 | FlexibilityNo cancel fee | On-time63% | |
| Cheapest$318 | Average$555 | FlexibilityNo cancel fee | On-time71% | |
| Cheapest$318 | Average$452 | FlexibilityNo cancel fee | On-timeN/A | |
| Cheapest$349 | Average$626 | FlexibilityNo cancel fee | On-time69% |