Cheap Flight Tickets from Washington (IAD) to Ontario (ONT), Starting at $749

Good to Know: Cheapest and Fastest IAD - ONT Flights

Useful information for finding best airline tickets from Washington Dulles International to Ontario International on your next trip.

Cheapest Round Trip Flight

$749

DL Delta Airlines • 1 stop • 30h 59m

Dec 18 – Dec 30

The cheapest round trip flight from Washington to Ontario (IAD-ONT-IAD) is currently $749

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Fastest Flight

12h 24m

The fastest nonstop flight from Washington to Ontario (IAD-ONT) takes 12h 24m

Top Airlines Flying from Washington to Ontario

Delta Airline, DL

Delta Airlines

Latest Flight Deals from Washington (IAD) to Ontario (ONT)

Compare and book low fare round-trip air tickets from Washington to Ontario. Ideal for travelers with confirmed return itineraries.

Dec 18 - Dec 30, Economy
DL
Washington → Ontario
30h 59m
7:00 AM - 10:59 PM • 1 stop
DL
Washington → Ontario
10h 38m
6:00 AM - 3:38 PM • 1 stop
$749
Delta Airlines
Dec 18 - Dec 30, Economy
DL
Washington → Ontario
21h 55m
7:00 AM - 5:15 PM • 1 stop
DL
Washington → Ontario
10h 38m
6:00 AM - 3:38 PM • 1 stop
$749
Delta Airlines
Dec 18 - Dec 30, Economy
DL
Washington → Ontario
12h 35m
5:00 PM - 9:55 PM • 1 stop
DL
Washington → Ontario
13h 35m
10:35 PM - 9:50 AM • 1 stop
$1078
Delta Airlines
Dec 18 - Dec 30, Economy
DL
Washington → Ontario
13h 27m
6:00 AM - 11:07 AM • 1 stop
DL
Washington → Ontario
13h 35m
10:35 PM - 9:50 AM • 1 stop
$1148
Delta Airlines
Dec 18 - Dec 30, Economy
DL
Washington → Ontario
12h 24m
3:00 PM - 7:44 PM • 1 stop
DL
Washington → Ontario
13h 35m
10:35 PM - 9:50 AM • 1 stop
$1388
Delta Airlines
Dec 18 - Dec 30, Economy
DL
Washington → Ontario
13h 37m
7:00 AM - 12:17 PM • 1 stop
DL
Washington → Ontario
12h 20m
1:01 PM - 11:41 PM • 1 stop
$1388
Delta Airlines

Fly from Washington to Ontario with the Best Airfare Deals on FareLeaders

Looking for a cheap last-minute deal or the best round-trip flight from Washington to Ontario? Find the biggest savings on one-way and round-trip tickets right here.

FAQs on Washington to Ontario Flights

What are the airports in Washington?
IAD,BWI,DCA
What’s the most popular airline flying from IAD to ONT?
The most popular airline flying from Washington to Ontario are
Can I fly from IAD to ONT non-stop?
NO
Which airlines fly nonstop between Washington and Ontario?
The non-stop flights between Washington and Ontario are .
What’s the earliest departure time from IAD to ONT Airport?
The earliest flight leaves IAD at 6:00 am and lands in ONT - Ontario International
What are the airports in Ontario?
ONT
Can I make changes to my Washington to Ontario flight tickets or cancel them on FareLeaders.com?
No. We are an airfare comparison site. All the tickets are booked by the travel agent offering the flight deal and any changes or cancellations to be made are directly done directly by them or the airlines.
Can I cancel my flight tickets from IAD to ONT?
Read the fare rules of the Washington to Ontario air tickets booked. Some airlines allow you to cancel the tickets within a stipulated time period with a cancellation fee.
Which airline alliances offer flights from Washington and Ontario?
operate flights between Washington and Ontario
How long does a flight from Washington to Ontario take?
It takes approximately 5 hour to fly non-stop from IAD to ONT, which is 2241.85 miles by air.
Which airlines provide the cheapest flights from Washington (IAD) to Ontario (ONT) ?
In the past couple of days, the cheapest tickets to ONT from IAD were found on DL : USD 749
Do I need a passport to fly between IAD and ONT?
No
What’s the latest departure time from IAD to ONT ?
The last flight leaves IAD at 5:00 pm

Washington (IAD) to Ontario (ONT): Airport Information

Origin Airport Washington Dulles International , Washington, US
Destination Airport Ontario International , Ontario, US
Distance 2242 miles

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