$133+ Cheap flights from Ontario (ONT) to Washington, D.C. (WAS)
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 9/19. Fares are subject to change and may not be available on all flights or dates of travel.
Find cheap flights from Ontario to Washington, D.C. 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.Cheapflights Tip: The best prices from Ontario to Washington, D.C. are usually found in May or August, booked 70 days in advance, depart on a Wednesday or Thursday and return on a Tuesday
Cheap flight deals from Ontario to Washington, D.C.
Discover tips and strategies to find the most affordable flight options for your journey from Ontario (ONT) to Washington, D.C. (WAS). 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 12, 2025.
Round-trip from | $255 (Frontier) |
|---|---|
One-way from | $133 (FlightHub) |
Popular in | September |
Cheapest in | May |
Average price | $345 |
Good round-trip deal | $383 or less |
Good one-way deal | $168 or less |
Find flight deals from Ontario to Washington, D.C.
Cheapest flights from Ontario to Washington, D.C.Explore the most affordable flight options available from Ontario to Washington, D.C.. Find the lowest fares from popular airlines and budget airlines, with prices last updated on June 12, 2025.
Explore the most affordable flight options available from Ontario to Washington, D.C.. Find the lowest fares from popular airlines and budget airlines, with prices last updated on June 12, 2025.
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.
This Kiwi.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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
This Southwest 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 Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
This American Airlines 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 American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
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.
This American Airlines 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 American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
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.
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.
This American 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 American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
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.
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.
This Southwest 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 Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Cheapflights Fare Finder
Customize your flight search to find flights from Ontario to Washington, D.C. 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 12, 2025.
Use the filters below to find and compare flights from Ontario to Washington, D.C. that are best for you.
Fly from
Fly to
Route
Depart
Return
Price
OntarioWashington, D.C.
ONT - IAD
ONTIAD
Ontario
Wed 7/9
7:22 pm-6:34 am
1 stop8h 12m
Washington, D.C. Dulles Intl
Tue 7/15
7:30 am-4:20 pm
1 stop11h 50m
OntarioWashington, D.C.
ONT - DCA
ONTDCA
Ontario
Thu 8/21
12:59 am-12:11 pm
1 stop8h 12m
Washington, D.C. Reagan-National
Wed 8/27
1:00 pm-11:50 pm
1 stop13h 50m
OntarioBaltimore
ONT - BWI
ONTBWI
Ontario
Mon 8/4
9:20 pm-5:10 am
Nonstop4h 50m
Baltimore/Washington
Mon 8/11
9:20 am-11:35 am
Nonstop5h 15m
OntarioWashington, D.C.
ONT - DCA
ONTDCA
Ontario
Thu 8/28
12:47 pm-1:05 am
1 stop9h 18m
Washington, D.C. Reagan-National
Tue 9/2
9:29 am-4:06 pm
1 stop9h 37m
OntarioWashington, D.C.
ONT - IAD
ONTIAD
Ontario
Fri 9/5
7:22 pm-7:32 am
1 stop9h 10m
Washington, D.C. Dulles Intl
Mon 9/8
6:09 pm-10:44 am
1 stop19h 35m
OntarioWashington, D.C.
ONT - IAD
ONTIAD
Ontario
Thu 8/7
11:59 pm-11:01 am
1 stop8h 02m
Washington, D.C. Dulles Intl
Sun 8/10
6:27 am-11:53 am
1 stop8h 26m
OntarioBaltimore
ONT - BWI
ONTBWI
Ontario
Sun 8/3
12:59 am-4:31 pm
1 stop12h 32m
Baltimore/Washington
Mon 8/11
5:26 pm-11:50 pm
1 stop9h 24m
OntarioWashington, D.C.
ONT - DCA
ONTDCA
Ontario
Fri 8/22
10:00 pm-3:00 pm
2 stops14h 00m
Washington, D.C. Reagan-National
Mon 8/25
3:50 pm-10:40 pm
2 stops9h 50m
OntarioBaltimore
ONT - BWI
ONTBWI
Ontario
Wed 8/13
12:47 pm-11:02 pm
1 stop7h 15m
Baltimore/Washington
Wed 8/27
7:00 am-11:52 am
1 stop7h 52m
OntarioBaltimore
ONT - BWI
ONTBWI
Ontario
Thu 8/14
6:39 pm-10:03 am
2 stops12h 24m
Baltimore/Washington
Mon 8/18
5:20 pm-10:06 pm
1 stop7h 46m
Best time to book a flight from Ontario to Washington, D.C.
Have a flexible travel schedule? Discover the best time to fly to Washington, D.C. from Ontario with our price prediction graph.
Cheapflights Insights
Everything you need to know about your flight from Ontario to Washington, D.C.
How far ahead should I book a flight from Ontario to Washington, D.C.?
Use this chart to determine the optimal time to book a round-trip flight from Ontario to Washington, D.C.. Price data was last updated on June 9, 2025.
The price you pay for your flight from Ontario to Washington, D.C. may vary depending on when you book. For the best chance of a lower fare, look to book 25 days in advance of your trip. Fares are likely to increase a fortnight or so before your departure date.
What is the cheapest month to book a flight from Ontario to Washington, D.C.?
Currently, August is the cheapest month in which you can book a flight from Ontario to Washington, D.C. (average of $241). Flying from Ontario to Washington, D.C. in March is currently the most expensive (average of $290). 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 WAS?
Find hourly flight availability from Ontario to Washington, D.C.. Discover flight options and departure times throughout the day, allowing you to choose a departure time that suits your schedule. Data last updated June 12, 2025.
It’s typically best to fly out from Ontario to Washington, D.C. in the afternoon. Doing so could potentially save you 32% on the flight price compared to flying at noon, which is usually more expensive.
What is the cheapest day to fly from Ontario to Washington, D.C.?
Use this chart to determine the cheapest time to fly round-trip from Ontario to Washington, D.C.. Price data was last updated on June 8, 2025.
Travelers seeking maximum savings on their Ontario to Washington, D.C. flight should consider departing on Wednesday evenings when fares are most often at their lowest. Monday mornings flights should be avoided if possible as fares are typically the most expensive at this time.
Rainfall in Washington, D.C. by month
Plan your trip to Washington, D.C. by taking into account the average rainfall totals by month.
In terms of precipitation, rainfall in Washington, D.C. ranges from 2.6 - 4.0 inches per month. May is typically the wettest month, when rainfall can reach 4.0 in. February is typically the driest time to visit Washington, D.C. when rainfall is around 2.6 in.
Temperature in Washington, D.C. by month
Plan your trip to Washington, D.C. by taking into account the average temperature totals by month.
If weather is an important factor for your trip to Washington, D.C., use this chart to help with planning. For those seeking warmer temperatures, July is the ideal time of year to visit, when temperatures reach an average of 80.6 F. Travelers looking to avoid the cold should look outside of January, when temperatures are typically at their lowest (around 35.6 F).
Reviews of airlines servicing Washington, D.C.
Get insights into the airlines that provide service to Washington, D.C.. 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, D.C.. Reviews last updated June 12, 2025.
Get a feel of what it's like to fly with Alaska Airlines, Southwest and Delta from Ontario to Washington, D.C. by reading reviews from past customers. In addition to providing an overall rating, users have also rated airlines in terms of entertainment options, comfort, food, crew/service, and boarding process.
Entertainment
Crew
Overall
Comfort
Boarding
Food
Reviews
James,Apr 2025
LAX - SFO
Entertainment
Crew
Overall
Comfort
Boarding
Food
Reviews
James,Apr 2025
LAX - SFO
Entertainment
Crew
Overall
Comfort
Boarding
Food
Reviews
James,Apr 2025
LAX - SFO
Entertainment
Crew
Overall
Comfort
Boarding
Food
Reviews
James,Apr 2025
LAX - SFO
Entertainment
Crew
Overall
Comfort
Boarding
Food
Reviews
James,Apr 2025
LAX - SFO
Entertainment
Crew
Overall
Comfort
Boarding
Food
Reviews
James,Apr 2025
LAX - SFO
Related info for your journey
Find useful and relevant information for your journey from Ontario to Washington, D.C.. 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, D.C.
See prices for flight routes from nearby airports that may be better suited for you.
Top 6 airlines flying from Ontario to Washington, D.C.
Discover the top 6 airlines that operate flights from Ontario to Washington, D.C.. 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 12, 2025.
| Airline | Cheapest | Average | Flexibility | On-time |
|---|---|---|---|---|
| Cheapest$130 | Average$191 | FlexibilityNo cancel fee | On-time65% | |
| Cheapest$141 | Average$262 | FlexibilityNo cancel fee | On-time62% | |
| Cheapest$256 | Average$456 | FlexibilityNo cancel fee | On-time69% | |
| Cheapest$286 | Average$412 | FlexibilityNo cancel fee | On-timeN/A | |
| Cheapest$286 | Average$504 | FlexibilityNo cancel fee | On-time71% | |
| Cheapest$326 | Average$465 | FlexibilityNo cancel fee | On-time63% |