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Amazing Delta ONT to SEA Flight Deals

The cheapest flights to Seattle - Tacoma Intl. found within the past 7 days were round trip and $69 one way. Prices and availability subject to change. Additional terms may apply.


Carrier Flight Depart ONT Arrive SEA Fri
11/27
Sat
11/28
Sun
11/29
Mon
11/30
Tue
12/1
Wed
12/2
Thu
12/3
Stops
DL 3673 03:15 pm 05:57 pm Check fare Check fare Check fare Check fare Check fare Check fare Check fare 0 stop(s)
DL 3608 05:40 pm 08:25 pm - Check fare Check fare Check fare Check fare Check fare Check fare 0 stop(s)

FAQs about Delta Air Lines Flights from ONT to SEA

What terminal is Delta Air Lines at Ontario, CA (ONT-Los Angeles - Ontario Intl.)?

Check your boarding pass to find out which Ontario, CA (ONT-Los Angeles - Ontario Intl.) terminal you'll be departing from on your way to Seattle, WA (SEA-Seattle - Tacoma Intl.) with Delta Air Lines. If you can't locate the information on there, ask your airline.

Are there Delta Air Lines non-stop flights from ONT to SEA?

If you're looking at flights with Delta Air Lines from Ontario, CA (ONT-Los Angeles - Ontario Intl.) to Seattle, WA (SEA-Seattle - Tacoma Intl.), you'll have to make at least one stopover. While you're waiting for your connecting flight, use the time to pick up a snack or stretch your legs.

How long is a Delta Air Lines flight from ONT to SEA?

Watch a movie or two, listen to music through your headphones or just put your seat back and forget your worries. Whatever interests you, find a way to while away the 4 hours and 14 minutes that it takes to journey from Ontario, CA (ONT-Los Angeles - Ontario Intl.) to Seattle, WA (SEA-Seattle - Tacoma Intl.) with Delta Air Lines.

How many direct and indirect flights does Delta Air Lines fly from ONT to SEA?

When heading from ONT to SEA, you'll find there are at least 4 Delta Air Lines daily flights to choose from.

If I am not able to travel due to COVID-19, can I change my booking to a later date?

For more info about changing your flight to Seattle, WA (SEA-Seattle - Tacoma Intl.), please visit our Customer Service Portal.

What is the best day to buy a plane ticket?

This just in! Airfares offered on Tuesdays tend to be the cheapest, according to flight demand on Travelocity in 2019. Wednesday and Friday prices are also good, but you may want to prepare your budget if booking on a Monday, as data shows the start of the week is when prices are generally at their highest.

What are the cheapest days to fly?

Frequent travelers may already know this, but earlier in the week can be the cheapest time to fly. In 2019, flights departing on a Tuesday were generally the cheapest of the week, whereas you may pay a premium for weekend flights when demand is usually high. On average, tickets were most expensive for Saturday departures, so if you need to fly out on a weekend, you might look for deals ahead of time.

How far in advance can you book a flight?

Trying to figure out how early you should book your flight? It's possible to start comparing international airfares on Travelocity up to 12 months in advance. However, it does depend on the carrier as not all airlines release their prices that far out. According to our 2019 flight demand trends, last minute planners can still bag a bargain with some of the cheapest fares appearing 1-2 weeks prior to their travel dates.

How can I save money on airline tickets?

We'll let you in on a secret...You can save big on flights if you mix and match your airlines and fare types. In fact, travelers who booked flights on Travelocity in 2019 saved nearly 50% when their return flights consisted of two different airlines or fare types.

*According to flight demand on Travelocity.com from January to December 2019. Savings are subject to change based on departure location, date and destination.

*Price based on the lowest price found within past 24 hours and based upon one night stay for two adults over the next thirty days. Prices and availability subject to change. Additional terms may apply.