ONT

$70 Find Cheap Flights from Washington to Ontario - Compare and Save

This is the cheapest one-way flight price found by a KAYAK user in the last 72 hours by searching for a flight to Ontario departing on 11/9. Fares are subject to change and may not be available on all flights or dates of travel. Click the price to replicate the search for this deal.
1 adult
1 adult, Economy, 0 bags

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Flight Deals

Cheap Flights from Washington to Ontario

 
Here are some of the best deals found on KAYAK recently from the most popular airlines for round-trip flights from Washington to Ontario that are departing in the next months. While these flights were available on KAYAK in the last 72 hours, prices and availability are subject to change and deals may expire.
Discover the best prices for you by selecting your travel dates on KAYAK.

Recent round-trip flight deals from Washington to Ontario

Mon, Sep 28 - Mon, Oct 5
Frontier Logo
10:53 am - 1:45 pmSEA  Seattle/Tacoma Intl-ONT Ontario
2h 52mnonstop
Frontier Logo
11:45 am - 3:08 pmONT  Ontario-SEA Seattle/Tacoma Intl
27h 23m1 stop Denver Intl
$150Frontier
Wed, Sep 23 - Sun, Sep 27
Frontier Logo
10:53 am - 1:45 pmSEA  Seattle/Tacoma Intl-ONT Ontario
2h 52mnonstop
Frontier Logo
5:44 pm - 8:40 pmONT  Ontario-SEA Seattle/Tacoma Intl
2h 56mnonstop
$151Frontier
Tue, Oct 13 - Wed, Oct 28
Multiple Airlines Logo
10:58 am - 5:05 pmSEA  Seattle/Tacoma Intl-ONT Ontario
6h 07m1 stop Santa Rosa Sonoma County
Multiple Airlines Logo
5:05 pm - 8:01 pmONT  Ontario-SEA Seattle/Tacoma Intl
2h 56mnonstop
$198Multiple Airlines
Wed, Sep 16 - Wed, Sep 23
Multiple Airlines Logo
9:55 am - 4:10 pmSEA  Seattle/Tacoma Intl-ONT Ontario
6h 15m1 stop Boise Air Term. Gowen Fld
Multiple Airlines Logo
5:44 pm - 8:40 pmONT  Ontario-SEA Seattle/Tacoma Intl
2h 56mnonstop
$198Multiple Airlines
Sat, Sep 19 - Wed, Sep 23
Southwest Logo
3:35 pm - 7:50 pmSEA  Seattle/Tacoma Intl-ONT Ontario
4h 15m1 stop Oakland
Southwest Logo
1:10 pm - 9:15 pmONT  Ontario-SEA Seattle/Tacoma Intl
8h 05m1 stop Phoenix Sky Harbor Intl
$242Southwest
Tue, Oct 6 - Wed, Oct 7
Southwest Logo
10:45 am - 7:35 pmPDX  Portland-ONT Ontario
8h 50m2 stops San Diego Las Vegas Harry Reid Intl
Southwest Logo
6:40 am - 10:10 amONT  Ontario-PDX Portland
3h 30m1 stop Oakland
$245Southwest
Fri, Oct 2 - Thu, Oct 8
Delta Logo
7:15 pm - 11:47 pmPDX  Portland-ONT Ontario
4h 32m1 stop Salt Lake City
Delta Logo
11:56 am - 8:00 pmONT  Ontario-PDX Portland
8h 04m1 stop Seattle/Tacoma Intl
$246Delta
Fri, Sep 11 - Sun, Sep 13
Delta Logo
5:50 pm - 10:40 pmPDX  Portland-ONT Ontario
4h 50m1 stop Seattle/Tacoma Intl
Delta Logo
6:00 am - 11:46 amONT  Ontario-PDX Portland
5h 46m1 stop Seattle/Tacoma Intl
$247Delta
Wed, Sep 30 - Tue, Oct 6
Alaska Airlines Logo
11:29 am - 2:16 pmSEA  Seattle/Tacoma Intl-ONT Ontario
2h 47mnonstop
Alaska Airlines Logo
6:02 am - 8:49 amONT  Ontario-SEA Seattle/Tacoma Intl
2h 47mnonstop
$247Alaska Airlines
Sat, Oct 24 - Tue, Oct 27
Alaska Airlines Logo
7:30 am - 10:17 amSEA  Seattle/Tacoma Intl-ONT Ontario
2h 47mnonstop
Alaska Airlines Logo
6:02 am - 8:49 amONT  Ontario-SEA Seattle/Tacoma Intl
2h 47mnonstop
$247Alaska Airlines
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Good to know

Low season

January

Cheapest flight

$70
Best time to beat the crowds with an average 10% drop in price.
Most popular time to fly and prices are also 3% lower on average.
Flight from Portland to Ontario

Flights from Washington to Ontario: the best tips from KAYAK users

Insights shared by verified travelers who flew the route from Washington to Ontario 
Learn how KAYAK collects reviews and tips from users.
Verified travelerFlew with Hawaiian Airlines-Jun 2025
Make sure to be there on time because the bag drop off can be a little complicated and it takes quite some time to get to the gate.
Verified travelerFlew with Alaska Airlines-Oct 2024
SeaTac lets you make an appointment to get through security. SpotSaver. No cost. Online.

FAQs for booking flights from Washington to Ontario

  • How does KAYAK find such low prices on flights from Washington to Ontario?

    KAYAK is a travel search engine. That means we look across the web to find the best prices we can find for our users. With over 2 billion flight queries processed yearly, we are able to display a variety of prices and options on flights from Washington to Ontario.

  • How does KAYAK's flight Price Forecast tool help me choose the right time to buy my flight ticket from Washington to Ontario?

    KAYAK’s flight Price Forecast tool uses historical data to determine whether the price for a flight to Ontario from Washington is likely to change within 7 days, so travelers know whether to wait or book now.

  • What is the Hacker Fare option on flights from Washington to Ontario?

    Hacker Fares allow you to combine one-way tickets in order to save you money over a traditional round-trip ticket. You could then fly to Ontario with an airline and back to Washington with another airline.

  • What is KAYAK's "flexible dates" feature and why should I care when looking for a flight from Washington to Ontario?

    Sometimes travel dates aren't set in stone. If your preferred travel dates have some wiggle room, flexible dates will show you all the options when flying to Ontario from Washington up to 3 days before/after your preferred dates. You can then pick the flights that suit you best.

Everything you need to know for your flight to Ontario

Information on the airport you'll fly into in Ontario

Ontario (ONT)