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Amazing Frontier Airlines ONT to SEA Flight Deals

The cheapest flights to Seattle - Tacoma Intl. found within the past 7 days were $164 round trip and $94 one way. Prices and availability subject to change. Additional terms may apply.

SEA From ONT Economy Coach Packages on Similar Airlines



FAQs about Frontier Airlines Flights from ONT to SEA

What terminal is Frontier Airlines at Ontario, CA (ONT-Los Angeles - Ontario Intl.)?

As soon as you're given your ticket for your Frontier Airlines flight from Ontario, CA (ONT-Los Angeles - Ontario Intl.) to Seattle, WA (SEA-Seattle - Tacoma Intl.), check if the terminal details are listed on it. If not, you might like to consult your carrier. They should be able to advise where you'll be flying into and out of.

Are there Frontier Airlines non-stop flights from ONT to SEA?

If you're considering flying with Frontier Airlines from Ontario, CA (ONT-Los Angeles - Ontario Intl.) to Seattle, WA (SEA-Seattle - Tacoma Intl.), you'll have to make a stopover. While you're waiting for your connection, take the chance to enjoy a bite to eat or go for a stroll.

How long is a Frontier Airlines flight from ONT to SEA?

As it will take roughly 5 hours and 28 minutes for your Frontier Airlines flight to journey from ONT to SEA, think about tossing some fun travel games in your cabin bag. You never know — the person sitting beside you might appreciate the chance to play to break up the journey.

How many direct and indirect flights does Frontier Airlines fly from ONT to SEA?

Each month, Frontier Airlines flies from Ontario, CA (ONT-Los Angeles - Ontario Intl.) to Seattle, WA (SEA-Seattle - Tacoma Intl.) about 23 times.

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.