Find Cheap Flights from Washington Dulles Intl to Ontario (IAD - ONT)

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Sat 11/18
Sat 11/25
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Good to Know

Average Price:
$427
(avg. price over the last 2 weeks)
Good Deal:
$311
or less (round trip)

When to Book Flights from Washington Dulles Intl to Ontario

Average price per month
Flight prices as travel date approaches
-1 day
-2 days

Top tips for Finding a Cheap Flight

When looking for a cheap flight, consider that 25% of our users selected a flight on this route for $310 or less.
The cheapest flight from Washington Dulles Intl to Ontario was found 47 days before departure, on average.
Book at least 3 weeks before departure in order to get a below-average price.
Morning departure is around 98% more expensive than an evening flight, on average*.
*Average of the lowest prices shown in KAYAK’s search results for departures within the next 30 days

FAQs for Booking Washington Dulles Intl to Ontario Flights

How long does a flight from Washington Dulles Intl to Ontario take?
An average nonstop flight takes 7h 40m, covering a distance of 2238 miles.
Which airlines provide the cheapest flights from Washington Dulles Intl to Ontario?
In the past 3 days, the cheapest round-trip tickets were found on Multiple Airlines ($228) and Frontier ($229)
Do I need a passport to fly between Washington Dulles Intl and Ontario?
No.
What’s the cheapest day of the week to fly Washington Dulles Intl to Ontario?
For Washington Dulles Intl to Ontario, Wednesday is the cheapest day to fly on average and Friday is the most expensive. Flying from Ontario back to Washington Dulles Intl, the best deals are generally found on Wednesday, with Monday being the most expensive.

Book cheap flights from Washington Dulles Intl to Ontario (round-trip)

Airports
Origin
Washington
$228
only
$228
Destination
Ontario
$228
only
$228
Wed, Dec 6
IAD
ONT
22h 50m
Fri, Dec 8
ONT
IAD
6h 40m
Trip: 3 days
Overall 0.0 Poor
Based on 0 reviews
Thu, Nov 30
IAD
ONT
7h 52m
Sat, Jan 20
ONT
IAD
6h 50m
Trip: 52 days
5.6OkayShow reviews
Overall 5.6 Okay
Based on 32923 reviews
Overall
5.9
Boarding
6.4
Comfort
5.4
Crew
6.8
Entertainment
4.5
Food
4.7
PVD
TPA
Excellent 9.3

Cheap, comfortable and friendly staff

Getting off the plane took forever on both legs.

PBI
ISP
Mediocre 2.0

Was unable to make it

DEN
ORD
Okay 5.3

Low cost

They make you pay for everything. Even peanuts. No entertainment.

PHL
MIA
Excellent 10.0

Same as all the other airlines in my opinion. Just way more afreoadable.

MCO
DEN
Okay 4.6

The seats were clean; the cabin looked very nice. The plane got me from point A to B safely. smoothest Lansing ever!

Flight was delayed 2.5 hours. No communication from the cockpit, 2 out of the 4 flight attendants we really crabby. Undersea storage was unusually small. I’m 5’8” and my knees were pressed against the seat in front of me and the seats are hard. My legs were numb for part of the trip.

Fri, Dec 1
IAD
ONT
7h 55m
Thu, Dec 7
ONT
IAD
6h 33m
Trip: 7 days
5.6OkayShow reviews
Overall 5.6 Okay
Based on 32923 reviews
Overall
5.9
Boarding
6.4
Comfort
5.4
Crew
6.8
Entertainment
4.5
Food
4.7
DEN
SLC
Okay 5.6

Food, entertainment NA, didn’t use. Rest of flight uneventful, happy to say. Because this was so late due to previous leg of journey delayed, our planned transportation to hotel wa not available.

FSD
DEN
Okay 4.6

The scheduled plane had a mechanical problem so we deplaned for alternative plan. It took six long hours to get another plane in. Meantime passengers stood in line for hours to make other arrangements. It would have been appropriate for the airline to call in extra staff to help stranded passengers. We missed the scheduled connecting flight and a tour. We got in at 1:00 am, 12 hours later than planned. We had meetings next day and were very tired because we got in so late

MIA
PHL
Okay 5.6

Flight was on time. The flight was fast and the crew was helpful and courteous

It was cramped. Couldn't recline back. Was only offered water

DEN
ORD
Excellent 10.0

On time. Very organized.

PBI
ISP
Mediocre 2.0

Was unable to make it

Sat, Jan 6
IAD
ONT
8h 11m
Fri, Jan 12
ONT
IAD
6h 50m
Trip: 7 days
5.6OkayShow reviews
Overall 5.6 Okay
Based on 32923 reviews
Overall
5.9
Boarding
6.4
Comfort
5.4
Crew
6.8
Entertainment
4.5
Food
4.7
MIA
ISP
Excellent 8.5

The terminal was empty. Plenty of seats. Boarding doesn't take long. Arrival at ISP is nice because it is small and empty.

MIA
CVG
Good 6.0

More snack/food options

LGA
MIA
Mediocre 3.6

Flight Very late , when departure already at night Uncomfortable seats $45 for a bag and I have drop it off myself after pay

DEN
ORD
Okay 5.3

Low cost

They make you pay for everything. Even peanuts. No entertainment.

PBI
ISP
Mediocre 2.0

Was unable to make it

Fri, Jan 5
IAD
ONT
8h 11m
Wed, Jan 10
ONT
IAD
6h 23m
Trip: 6 days
Overall 0.0 Poor
Based on 0 reviews
Thu, Feb 1
IAD
ONT
8h 05m
Sat, Feb 3
ONT
IAD
6h 50m
Trip: 3 days
5.6OkayShow reviews
Overall 5.6 Okay
Based on 32923 reviews
Overall
5.9
Boarding
6.4
Comfort
5.4
Crew
6.8
Entertainment
4.5
Food
4.7
DEN
SLC
Okay 5.6

Food, entertainment NA, didn’t use. Rest of flight uneventful, happy to say. Because this was so late due to previous leg of journey delayed, our planned transportation to hotel wa not available.

PBI
ISP
Mediocre 2.0

Was unable to make it

DEN
ORD
Okay 5.3

Low cost

They make you pay for everything. Even peanuts. No entertainment.

FSD
DEN
Okay 4.6

The scheduled plane had a mechanical problem so we deplaned for alternative plan. It took six long hours to get another plane in. Meantime passengers stood in line for hours to make other arrangements. It would have been appropriate for the airline to call in extra staff to help stranded passengers. We missed the scheduled connecting flight and a tour. We got in at 1:00 am, 12 hours later than planned. We had meetings next day and were very tired because we got in so late

PVD
TPA
Excellent 9.3

Cheap, comfortable and friendly staff

Getting off the plane took forever on both legs.

Mon, Nov 20
IAD
ONT
7h 55m
Tue, Nov 28
ONT
IAD
30h 40m
Trip: 9 days
Overall 0.0 Poor
Based on 0 reviews
Sat, Feb 3
IAD
ONT
8h 11m
Fri, Feb 9
ONT
IAD
6h 50m
Trip: 7 days
5.6OkayShow reviews
Overall 5.6 Okay
Based on 32923 reviews
Overall
5.9
Boarding
6.4
Comfort
5.4
Crew
6.8
Entertainment
4.5
Food
4.7
PBI
ISP
Mediocre 2.0

Was unable to make it

PVD
TPA
Excellent 9.3

Cheap, comfortable and friendly staff

Getting off the plane took forever on both legs.

DEN
ORD
Okay 5.3

Low cost

They make you pay for everything. Even peanuts. No entertainment.

MIA
CVG
Good 6.0

More snack/food options

MIA
ISP
Excellent 8.5

The terminal was empty. Plenty of seats. Boarding doesn't take long. Arrival at ISP is nice because it is small and empty.

Tue, Apr 3
IAD
ONT
7h 49m
Sat, Apr 7
ONT
IAD
6h 50m
Trip: 5 days
5.6OkayShow reviews
Overall 5.6 Okay
Based on 32923 reviews
Overall
5.9
Boarding
6.4
Comfort
5.4
Crew
6.8
Entertainment
4.5
Food
4.7
MIA
ISP
Excellent 8.5

The terminal was empty. Plenty of seats. Boarding doesn't take long. Arrival at ISP is nice because it is small and empty.

LGA
MIA
Mediocre 3.6

Flight Very late , when departure already at night Uncomfortable seats $45 for a bag and I have drop it off myself after pay

DEN
SLC
Okay 5.6

Food, entertainment NA, didn’t use. Rest of flight uneventful, happy to say. Because this was so late due to previous leg of journey delayed, our planned transportation to hotel wa not available.

MCO
DEN
Okay 4.6

The seats were clean; the cabin looked very nice. The plane got me from point A to B safely. smoothest Lansing ever!

Flight was delayed 2.5 hours. No communication from the cockpit, 2 out of the 4 flight attendants we really crabby. Undersea storage was unusually small. I’m 5’8” and my knees were pressed against the seat in front of me and the seats are hard. My legs were numb for part of the trip.

FSD
DEN
Okay 4.6

The scheduled plane had a mechanical problem so we deplaned for alternative plan. It took six long hours to get another plane in. Meantime passengers stood in line for hours to make other arrangements. It would have been appropriate for the airline to call in extra staff to help stranded passengers. We missed the scheduled connecting flight and a tour. We got in at 1:00 am, 12 hours later than planned. We had meetings next day and were very tired because we got in so late

Sat, Jan 13
IAD
ONT
8h 11m
Tue, Jan 16
ONT
IAD
6h 46m
Trip: 4 days
5.6OkayShow reviews
Overall 5.6 Okay
Based on 32923 reviews
Overall
5.9
Boarding
6.4
Comfort
5.4
Crew
6.8
Entertainment
4.5
Food
4.7
MIA
PHL
Okay 5.6

Flight was on time. The flight was fast and the crew was helpful and courteous

It was cramped. Couldn't recline back. Was only offered water

PVD
TPA
Excellent 9.3

Cheap, comfortable and friendly staff

Getting off the plane took forever on both legs.

FSD
DEN
Okay 4.6

The scheduled plane had a mechanical problem so we deplaned for alternative plan. It took six long hours to get another plane in. Meantime passengers stood in line for hours to make other arrangements. It would have been appropriate for the airline to call in extra staff to help stranded passengers. We missed the scheduled connecting flight and a tour. We got in at 1:00 am, 12 hours later than planned. We had meetings next day and were very tired because we got in so late

MCO
DEN
Okay 4.6

The seats were clean; the cabin looked very nice. The plane got me from point A to B safely. smoothest Lansing ever!

Flight was delayed 2.5 hours. No communication from the cockpit, 2 out of the 4 flight attendants we really crabby. Undersea storage was unusually small. I’m 5’8” and my knees were pressed against the seat in front of me and the seats are hard. My legs were numb for part of the trip.

MIA
CVG
Good 6.0

More snack/food options

Tue, Mar 6
IAD
ONT
7h 49m
Tue, Mar 13
ONT
IAD
6h 52m
Trip: 7 days
5.6OkayShow reviews
Overall 5.6 Okay
Based on 32923 reviews
Overall
5.9
Boarding
6.4
Comfort
5.4
Crew
6.8
Entertainment
4.5
Food
4.7
DEN
ORD
Okay 5.3

Low cost

They make you pay for everything. Even peanuts. No entertainment.

MIA
PHL
Okay 5.6

Flight was on time. The flight was fast and the crew was helpful and courteous

It was cramped. Couldn't recline back. Was only offered water

LGA
MIA
Mediocre 3.6

Flight Very late , when departure already at night Uncomfortable seats $45 for a bag and I have drop it off myself after pay

MIA
CVG
Good 6.0

More snack/food options

PBI
ISP
Mediocre 2.0

Was unable to make it

Sat, Mar 31
IAD
ONT
7h 40m
Mon, Apr 23
ONT
IAD
7h 30m
Trip: 24 days
5.6OkayShow reviews
Overall 5.6 Okay
Based on 32923 reviews
Overall
5.9
Boarding
6.4
Comfort
5.4
Crew
6.8
Entertainment
4.5
Food
4.7
DEN
ORD
Okay 5.3

Low cost

They make you pay for everything. Even peanuts. No entertainment.

MIA
PHL
Okay 5.6

Flight was on time. The flight was fast and the crew was helpful and courteous

It was cramped. Couldn't recline back. Was only offered water

PHL
MIA
Excellent 10.0

Same as all the other airlines in my opinion. Just way more afreoadable.

DEN
SLC
Okay 5.6

Food, entertainment NA, didn’t use. Rest of flight uneventful, happy to say. Because this was so late due to previous leg of journey delayed, our planned transportation to hotel wa not available.

MIA
CVG
Good 6.0

More snack/food options

Fri, Apr 20
IAD
ONT
15h 55m
Mon, Apr 23
ONT
IAD
7h 30m
Trip: 4 days
5.6OkayShow reviews
Overall 5.6 Okay
Based on 32923 reviews
Overall
5.9
Boarding
6.4
Comfort
5.4
Crew
6.8
Entertainment
4.5
Food
4.7
PBI
ISP
Mediocre 2.0

Was unable to make it

PHL
MIA
Excellent 10.0

Same as all the other airlines in my opinion. Just way more afreoadable.

MIA
CVG
Good 6.0

More snack/food options

DEN
SLC
Okay 5.6

Food, entertainment NA, didn’t use. Rest of flight uneventful, happy to say. Because this was so late due to previous leg of journey delayed, our planned transportation to hotel wa not available.

DEN
ORD
Excellent 10.0

On time. Very organized.

Sat, Mar 24
IAD
ONT
7h 40m
Sat, Mar 31
ONT
IAD
6h 50m
Trip: 8 days
5.6OkayShow reviews
Overall 5.6 Okay
Based on 32923 reviews
Overall
5.9
Boarding
6.4
Comfort
5.4
Crew
6.8
Entertainment
4.5
Food
4.7
PVD
TPA
Excellent 9.3

Cheap, comfortable and friendly staff

Getting off the plane took forever on both legs.

MIA
ISP
Excellent 8.5

The terminal was empty. Plenty of seats. Boarding doesn't take long. Arrival at ISP is nice because it is small and empty.

FSD
DEN
Okay 4.6

The scheduled plane had a mechanical problem so we deplaned for alternative plan. It took six long hours to get another plane in. Meantime passengers stood in line for hours to make other arrangements. It would have been appropriate for the airline to call in extra staff to help stranded passengers. We missed the scheduled connecting flight and a tour. We got in at 1:00 am, 12 hours later than planned. We had meetings next day and were very tired because we got in so late

DEN
SLC
Okay 5.6

Food, entertainment NA, didn’t use. Rest of flight uneventful, happy to say. Because this was so late due to previous leg of journey delayed, our planned transportation to hotel wa not available.

PBI
ISP
Mediocre 2.0

Was unable to make it

Wed, May 23
IAD
ONT
15h 43m
Tue, May 29
ONT
IAD
17h 03m
Trip: 7 days
5.6OkayShow reviews
Overall 5.6 Okay
Based on 32923 reviews
Overall
5.9
Boarding
6.4
Comfort
5.4
Crew
6.8
Entertainment
4.5
Food
4.7
MIA
CVG
Good 6.0

More snack/food options

DEN
ORD
Okay 5.3

Low cost

They make you pay for everything. Even peanuts. No entertainment.

MIA
PHL
Okay 5.6

Flight was on time. The flight was fast and the crew was helpful and courteous

It was cramped. Couldn't recline back. Was only offered water

PHL
MIA
Excellent 10.0

Same as all the other airlines in my opinion. Just way more afreoadable.

DEN
SLC
Okay 5.6

Food, entertainment NA, didn’t use. Rest of flight uneventful, happy to say. Because this was so late due to previous leg of journey delayed, our planned transportation to hotel wa not available.

Wed, Nov 29
IAD
ONT
7h 55m
Mon, Dec 4
ONT
IAD
6h 40m
Trip: 6 days
5.6OkayShow reviews
Overall 5.6 Okay
Based on 32923 reviews
Overall
5.9
Boarding
6.4
Comfort
5.4
Crew
6.8
Entertainment
4.5
Food
4.7
LGA
MIA
Mediocre 3.6

Flight Very late , when departure already at night Uncomfortable seats $45 for a bag and I have drop it off myself after pay

MCO
DEN
Okay 4.6

The seats were clean; the cabin looked very nice. The plane got me from point A to B safely. smoothest Lansing ever!

Flight was delayed 2.5 hours. No communication from the cockpit, 2 out of the 4 flight attendants we really crabby. Undersea storage was unusually small. I’m 5’8” and my knees were pressed against the seat in front of me and the seats are hard. My legs were numb for part of the trip.

DEN
ORD
Okay 5.3

Low cost

They make you pay for everything. Even peanuts. No entertainment.

MIA
ISP
Excellent 8.5

The terminal was empty. Plenty of seats. Boarding doesn't take long. Arrival at ISP is nice because it is small and empty.

MIA
CVG
Good 6.0

More snack/food options

Thu, Jan 4
IAD
ONT
8h 00m
Tue, Jan 9
ONT
IAD
6h 46m
Trip: 6 days
5.6OkayShow reviews
Overall 5.6 Okay
Based on 32923 reviews
Overall
5.9
Boarding
6.4
Comfort
5.4
Crew
6.8
Entertainment
4.5
Food
4.7
PVD
TPA
Excellent 9.3

Cheap, comfortable and friendly staff

Getting off the plane took forever on both legs.

DEN
ORD
Excellent 10.0

On time. Very organized.

MIA
PHL
Okay 5.6

Flight was on time. The flight was fast and the crew was helpful and courteous

It was cramped. Couldn't recline back. Was only offered water

MCO
DEN
Okay 4.6

The seats were clean; the cabin looked very nice. The plane got me from point A to B safely. smoothest Lansing ever!

Flight was delayed 2.5 hours. No communication from the cockpit, 2 out of the 4 flight attendants we really crabby. Undersea storage was unusually small. I’m 5’8” and my knees were pressed against the seat in front of me and the seats are hard. My legs were numb for part of the trip.

PHL
MIA
Excellent 10.0

Same as all the other airlines in my opinion. Just way more afreoadable.

Tue, Feb 13
IAD
ONT
8h 05m
Fri, Feb 16
ONT
IAD
6h 50m
Trip: 4 days
5.6OkayShow reviews
Overall 5.6 Okay
Based on 32923 reviews
Overall
5.9
Boarding
6.4
Comfort
5.4
Crew
6.8
Entertainment
4.5
Food
4.7
FSD
DEN
Okay 4.6

The scheduled plane had a mechanical problem so we deplaned for alternative plan. It took six long hours to get another plane in. Meantime passengers stood in line for hours to make other arrangements. It would have been appropriate for the airline to call in extra staff to help stranded passengers. We missed the scheduled connecting flight and a tour. We got in at 1:00 am, 12 hours later than planned. We had meetings next day and were very tired because we got in so late

DEN
ORD
Okay 5.3

Low cost

They make you pay for everything. Even peanuts. No entertainment.

MIA
ISP
Excellent 8.5

The terminal was empty. Plenty of seats. Boarding doesn't take long. Arrival at ISP is nice because it is small and empty.

DEN
ORD
Excellent 10.0

On time. Very organized.

MIA
PHL
Okay 5.6

Flight was on time. The flight was fast and the crew was helpful and courteous

It was cramped. Couldn't recline back. Was only offered water

Fri, Dec 8
IAD
ONT
7h 55m
Sun, Dec 17
ONT
IAD
6h 46m
Trip: 10 days
5.6OkayShow reviews
Overall 5.6 Okay
Based on 32923 reviews
Overall
5.9
Boarding
6.4
Comfort
5.4
Crew
6.8
Entertainment
4.5
Food
4.7
DEN
SLC
Okay 5.6

Food, entertainment NA, didn’t use. Rest of flight uneventful, happy to say. Because this was so late due to previous leg of journey delayed, our planned transportation to hotel wa not available.

PBI
ISP
Mediocre 2.0

Was unable to make it

DEN
ORD
Excellent 10.0

On time. Very organized.

MIA
PHL
Okay 5.6

Flight was on time. The flight was fast and the crew was helpful and courteous

It was cramped. Couldn't recline back. Was only offered water

MIA
ISP
Excellent 8.5

The terminal was empty. Plenty of seats. Boarding doesn't take long. Arrival at ISP is nice because it is small and empty.

Fri, May 4
IAD
ONT
15h 43m
Tue, May 8
ONT
IAD
17h 03m
Trip: 5 days
5.6OkayShow reviews
Overall 5.6 Okay
Based on 32923 reviews
Overall
5.9
Boarding
6.4
Comfort
5.4
Crew
6.8
Entertainment
4.5
Food
4.7
DEN
SLC
Okay 5.6

Food, entertainment NA, didn’t use. Rest of flight uneventful, happy to say. Because this was so late due to previous leg of journey delayed, our planned transportation to hotel wa not available.

PVD
TPA
Excellent 9.3

Cheap, comfortable and friendly staff

Getting off the plane took forever on both legs.

LGA
MIA
Mediocre 3.6

Flight Very late , when departure already at night Uncomfortable seats $45 for a bag and I have drop it off myself after pay

DEN
ORD
Excellent 10.0

On time. Very organized.

MIA
CVG
Good 6.0

More snack/food options

Show more results
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