How do most travelers feel about Delta?

Delta has received a 6.2/10 rating from 4,006 Cheapflights user reviews. If you wish to plan your next trip from Ontario to Seattle with Delta, enter your preferred travel dates above!

Can I get a flight from Ontario to Seattle on Delta for under $300?

15 Delta flights from ONT to SEA have recently been found on Cheapflights for under $300. Click here to find the best deals to Seattle for your desired dates.

How far ahead should I book a flight from Ontario to Seattle with Delta?

Booking with Delta 76 days in advance of your planned departure date is, on average, the best time to get cheap flights from Ontario to Seattle. The general trend is that the closer you book to the departure date, the more expensive your flight will be.

What is the cheapest month to book a flight from Ontario to Seattle with Delta?

Currently, the most affordable month to book a Delta flight from Ontario to Seattle in January, with an average price of $247. Conversely, traveling with Delta from Ontario to Seattle in July will be the most expensive, with an average cost of $406. Various factors influence flight prices, so comparing airlines, departure airports, and times can help reduce costs.

In terms of precipitation, rainfall in Seattle ranges from 0.7 - 6.6 inches per month. November is typically the wettest month, when rainfall can reach 6.6 in. July is typically the driest time to visit Seattle when rainfall is around 0.7 in.

Fly Delta from ONT to SEA as low as $88

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Cheapflights users flying from Ontario to Seattle on Delta typically fly into Seattle/Tacoma Intl and depart from Ontario. Select your dates above for pricing.

Delta flights from Ontario to Seattle in 2024

Popular in	December
Cheapest in	October
Average price (all airlines)	$218
One-way from	$88
Round-trip from	$167

Highest demand for flights from Ontario to Seattle/Tacoma Intl; 4% potential price increase.

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Best time to find cheap flights from Ontario to Seattle/Tacoma Intl; 1% potential price drop.

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Average price for all Ontario to Seattle/Tacoma Intl flights (one-way and round-trip).

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Cheapest one-way Delta flight from Ontario to Seattle/Tacoma Intl

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Cheapest round-trip Delta flight from Ontario to Seattle/Tacoma Intl

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Can I get a flight from Ontario to Seattle on Delta for under $300?
15 Delta flights from ONT to SEA have recently been found on Cheapflights for under $300. Click here to find the best deals to Seattle for your desired dates.
How do most travelers feel about Delta?
Delta has received a 6.2/10 rating from 4,006 Cheapflights user reviews. If you wish to plan your next trip from Ontario to Seattle with Delta, enter your preferred travel dates above!

Cheapest Delta flights from Ontario to Seattle

Wed 6/262:15 pmONT - SEA

Nonstop2h 44mDelta

Wed 7/35:30 amSEA - ONT

1 stop6h 48mDelta

Deal found 6/1$187

Pick Dates

Wed 6/2611:40 amONT - SEA

Nonstop2h 45mDelta

Sat 6/295:30 amSEA - ONT

1 stop6h 47mDelta

Deal found 6/1$212

Pick Dates

Tue 6/187:00 amONT - SEA

Nonstop2h 46mDelta

Sat 6/228:15 amSEA - ONT

Nonstop2h 45mDelta

Deal found 6/1$227

Pick Dates

Direct flights from Ontario to Seattle on Delta

Tue 7/97:00 amONT - SEA

Nonstop2h 50mDelta

Sat 7/137:55 pmSEA - ONT

Nonstop2h 47mDelta

Deal found 6/1$177

Pick Dates

Thu 8/296:59 pmONT - SEA

Nonstop2h 44mDelta

Thu 9/510:19 amSEA - ONT

Nonstop3h 01mDelta

Deal found 6/2$197

Pick Dates

Tue 6/187:00 amONT - SEA

Nonstop2h 46mDelta

Sat 6/228:15 amSEA - ONT

Nonstop2h 45mDelta

Deal found 6/1$227

Pick Dates

Last minute deals on Cheapflights

Tue 6/115:00 pmONT - SEA

1 stop6h 59mDelta

Wed 6/195:30 amSEA - ONT

1 stop6h 47mDelta

Deal found 6/1$331

Pick Dates

Sat 6/811:40 amONT - SEA

Nonstop2h 45mDelta

Sat 6/87:55 pmSEA - ONT

Nonstop2h 43mDelta

Deal found 6/1$367

Pick Dates

Tue 6/117:00 amONT - SEA

Nonstop2h 46mDelta

Fri 6/148:15 amSEA - ONT

Nonstop2h 45mDelta

Deal found 6/1$377

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One-way Delta flights to Seattle from Ontario

Wed 7/245:00 pmONT - SEA

1 stop7h 01mDelta

Deal found 6/1$88

Pick Dates

Tue 6/2511:40 amONT - SEA

Nonstop2h 45mDelta

Deal found 6/1$99

Pick Dates

Thu 8/85:00 pmONT - SEA

1 stop6h 57mDelta

Deal found 5/31$108

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Best time to book a flight from Ontario to Seattle

Have a flexible travel schedule? Discover the best time to fly to Seattle from Ontario with our price prediction graph.

Estimated round-trip price

Temperature and rainfall in Seattle by month

SEA Temperature	41 - 66.2 °F

SEA

Temperature

41 - 66.2 °F

If weather is an important factor for your trip to Seattle, 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 66.2 F. Travelers looking to avoid the cold should look outside of December, when temperatures are typically at their lowest (around 41.0 F).

Browse thousands of different options on Cheapflights for your next trip

Fly from Ontario to Seattle on another airline
Consider alternative airlines that service the Seattle area. Flight routes are based on user searches made on Cheapflights and were last updated on June 2, 2024.

Frontier flights from Ontario to Seattle/Tacoma Intl

Alaska Airlines flights from Ontario to Seattle/Tacoma Intl

Complete your trip
Complete your trip to Seattle by adding a car rental and/or hotel reservation to your travel itinerary.

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West Seattle car rentals

Other popular destinations in North America
If Seattle is not for you, choose from these other destinations located in North America. Flight routes are based on user searches made on Cheapflights and were last updated on June 2, 2024.

Flights to New York

Flights to Los Angeles

Flights to San Francisco

Flights to Fort Lauderdale

See what others are saying about Delta

Delta

8.0

Very good

10,402 reviews

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Overview

Recent reviews

3.9

Poor|Oct 2021

There were complications with my flights boarding in spokane and my secondary flight was changed without my consent to one that boarded at the same time as my first flight let me out on the opposite side of the massivr layover airport. It was only because an employee saw my struggle and confusion and hooked me up with a ride that I even made the flight dispite delta's best efforts. My TV's headphone jack on my first flight was also busted which sucked to find out after buying headphones on the flight. About halfway through the flight one of the attendants moved me to a seat with a working TV. Long story short Delta as an airline was terrible but their employees did their best to help me with what limited options they had to work with.

6.0

Okay|Apr 2022

No entertainment, five hour flight and choice of pretzels or a cookie. Still a place to put your cigarette in the restroom on board. How old is the plane?

5.9

Fair|Oct 2021

The staff was the highlight. Only thing that could have been better was the temperature on the flight from Hawaii to Seattle. The plane was too cold to get comfortable

10.0

Wonderful|Aug 2021

No complaints!!

2.0

Poor|Oct 2021

I never took this flight and was never able to cancel it in Kayak’s system! I will never book through Kayak again. The flight was probably fine. Next time I will only book with the airline directly. I would caution anyone else to do the same.

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Cheapflights users flying from Ontario to Seattle on Delta typically fly into Seattle/Tacoma Intl and depart from Ontario. Select your dates above for pricing.

Delta flights from Ontario to Seattle in 2024

Find detailed information about Delta flights from Ontario to Seattle. Explore the options provided by Delta to plan your journey from Ontario to Seattle. Data last updated June 2, 2024.

Popular in

Cheapest in

Average price (all airlines)

One-way from

Round-trip from

Can I get a flight from Ontario to Seattle on Delta for under $300?

How do most travelers feel about Delta?

Cheapest Delta flights from Ontario to Seattle

Direct flights from Ontario to Seattle on Delta

Last minute deals on Cheapflights

One-way Delta flights to Seattle from Ontario

Best time to book a flight from Ontario to Seattle

Have a flexible travel schedule? Discover the best time to fly to Seattle from Ontario with our price prediction graph.

Temperature and rainfall in Seattle by month

Plan your trip to Seattle by taking into account the average temperature and rainfall totals by month.

Browse thousands of different options on Cheapflights for your next trip

Toggle through the tabs below to find thousands of options on Cheapflights for your next trip.

Fly from Ontario to Seattle on another airline
Consider alternative airlines that service the Seattle area. Flight routes are based on user searches made on Cheapflights and were last updated on June 2, 2024.

Consider alternative airlines that service the Seattle area. Flight routes are based on user searches made on Cheapflights and were last updated on June 2, 2024.

Other Delta flights from Ontario
Browse through other Delta flights departing from Ontario. Flight routes are based on user searches made on Cheapflights and were last updated on June 2, 2024.

Browse through other Delta flights departing from Ontario. Flight routes are based on user searches made on Cheapflights and were last updated on June 2, 2024.

Complete your trip
Complete your trip to Seattle by adding a car rental and/or hotel reservation to your travel itinerary.

Complete your trip to Seattle by adding a car rental and/or hotel reservation to your travel itinerary.

Other airlines servicing Ontario and Seattle
Choose from other airlines serving Ontario and Seattle.

Choose from other airlines serving Ontario and Seattle.

Other popular destinations in North America
If Seattle is not for you, choose from these other destinations located in North America. Flight routes are based on user searches made on Cheapflights and were last updated on June 2, 2024.

If Seattle is not for you, choose from these other destinations located in North America. Flight routes are based on user searches made on Cheapflights and were last updated on June 2, 2024.

Popular flights with Delta
Browse through some of the most popular routes that Delta offers at this time. Flights are based on user searches made on Cheapflights and were last updated on June 2, 2024.

Browse through some of the most popular routes that Delta offers at this time. Flights are based on user searches made on Cheapflights and were last updated on June 2, 2024.

See what others are saying about Delta

Overview

Recent reviews

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Flights

Delta flights from Ontario to Seattle (ONT - SEA)

Cheapflights users flying from Ontario to Seattle on Delta typically fly into Seattle/Tacoma Intl and depart from Ontario. Select your dates above for pricing.

Delta flights from Ontario to Seattle in 2024

Find detailed information about Delta flights from Ontario to Seattle. Explore the options provided by Delta to plan your journey from Ontario to Seattle. Data last updated June 2, 2024.

Popular in

Cheapest in

Average price (all airlines)

One-way from

Round-trip from

Can I get a flight from Ontario to Seattle on Delta for under $300?

How do most travelers feel about Delta?

Cheapest Delta flights from Ontario to Seattle

Direct flights from Ontario to Seattle on Delta

Last minute deals on Cheapflights

One-way Delta flights to Seattle from Ontario

Best time to book a flight from Ontario to Seattle

Have a flexible travel schedule? Discover the best time to fly to Seattle from Ontario with our price prediction graph.

Temperature and rainfall in Seattle by month

Plan your trip to Seattle by taking into account the average temperature and rainfall totals by month.

Browse thousands of different options on Cheapflights for your next trip

Toggle through the tabs below to find thousands of options on Cheapflights for your next trip.

Fly from Ontario to Seattle on another airlineConsider alternative airlines that service the Seattle area. Flight routes are based on user searches made on Cheapflights and were last updated on June 2, 2024.

Consider alternative airlines that service the Seattle area. Flight routes are based on user searches made on Cheapflights and were last updated on June 2, 2024.

See what others are saying about Delta

Overview

100% Free

Book with Flexibility

Travel Smart

Fly from Ontario to Seattle on another airline
Consider alternative airlines that service the Seattle area. Flight routes are based on user searches made on Cheapflights and were last updated on June 2, 2024.