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Cheap flights from St. Louis to Ontario from $74

This is the cheapest one-way flight price found by a momondo user in the last 72 hours by searching for a flight from St. Louis to Ontario departing on 8/28. Fares may change, and may not be available for all flights or travel dates. Click the price to refresh the search for this deal.
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Fri 6/14

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Easily compare round-trip flights from St. Louis to Ontario

Below you can see the best fares for your round-trip flight route over the next six months. All fares were found on momondo this week. Browse the quickest and cheapest flights from St. Louis to Ontario by changing tabs
Frontier
Aug 28
STL8:00 pmLambert-St Louis
5h 39m
1 stop
ONT11:39 pmOntario
Sep 9
ONT12:49 amOntario
9h 01m
1 stop
STL11:50 amLambert-St Louis
Frontier
Aug 31
STL8:00 pmLambert-St Louis
5h 44m
1 stop
ONT11:44 pmOntario
Sep 17
ONT8:35 pmOntario
11h 43m
1 stop
STL10:18 amLambert-St Louis
Frontier
Aug 29
STL7:29 pmLambert-St Louis
19h 32m
1 stop
ONT1:01 pmOntario
Sep 2
ONT5:30 pmOntario
14h 48m
1 stop
STL10:18 amLambert-St Louis
Multiple Airlines
Aug 14
STL9:49 amLambert-St Louis
11h 26m
2 stops
ONT7:15 pmOntario
Aug 21
ONT8:35 pmOntario
11h 43m
1 stop
STL10:18 amLambert-St Louis
Frontier
Aug 14
STL8:00 pmLambert-St Louis
5h 39m
1 stop
ONT11:39 pmOntario
Aug 23
ONT12:49 amOntario
6h 48m
1 stop
STL9:37 amLambert-St Louis
Delta
Jul 2
STL6:25 pmLambert-St Louis
7h 16m
1 stop
ONT11:41 pmOntario
Jul 10
ONT5:00 pmOntario
5h 55m
1 stop
STL12:55 amLambert-St Louis

Find the cheapest one-way flights from St. Louis to Ontario

If you're looking for one-way flights from St. Louis to Ontario, view some of our deals below provided by Frontier
Frontier
Aug 28
STL8:00 pmLambert-St Louis
5h 39m
1 stop
ONT11:39 pmOntario
Frontier
Jun 15
STL7:29 pmLambert-St Louis
13h 34m
1 stop
ONT7:03 amOntario
Frontier
Jun 19
STL8:02 pmLambert-St Louis
5h 47m
1 stop
ONT11:49 pmOntario

Search last-minute flights to Ontario from St. Louis

Find and compare round-trip flight prices for your last-minute flight from St. Louis to Ontario
Frontier
Jun 8
STL8:02 pmLambert-St Louis
5h 55m
1 stop
ONT11:57 pmOntario
Jun 14
ONT12:44 amOntario
6h 45m
1 stop
STL9:29 amLambert-St Louis
Frontier
Jun 8
STL8:02 pmLambert-St Louis
5h 55m
1 stop
ONT11:57 pmOntario
Jun 14
ONT12:44 amOntario
6h 45m
1 stop
STL9:29 amLambert-St Louis
Frontier
Jun 8
STL8:02 pmLambert-St Louis
5h 55m
1 stop
ONT11:57 pmOntario
Jun 10
ONT9:36 pmOntario
15h 11m
1 stop
STL2:47 pmLambert-St Louis
Frontier
Jun 9
STL7:29 pmLambert-St Louis
24h 40m
1 stop
ONT6:09 pmOntario
Jun 14
ONT12:44 amOntario
6h 45m
1 stop
STL9:29 amLambert-St Louis
Frontier
Jun 8
STL8:02 pmLambert-St Louis
5h 55m
1 stop
ONT11:57 pmOntario
Jun 15
ONT9:44 amOntario
26h 53m
1 stop
STL2:37 pmLambert-St Louis
Multiple Airlines
Jun 8
STL7:35 amLambert-St Louis
13h 39m
2 stops
ONT7:14 pmOntario
Jun 9
ONT12:59 amOntario
6h 30m
1 stop
STL9:29 amLambert-St Louis

United Airlines flights from St. Louis to Ontario

Our best United Airlines deals on St. Louis to Ontario flight tickets
United Airlines
Sep 3
STL4:51 pmLambert-St Louis
6h 11m
1 stop
ONT9:02 pmOntario
Sep 14
ONT7:40 amOntario
7h 23m
1 stop
STL5:03 pmLambert-St Louis
United Airlines
Aug 5
STL5:03 pmLambert-St Louis
6h 08m
1 stop
ONT9:11 pmOntario
Aug 9
ONT6:25 pmOntario
18h 11m
2 stops
STL2:36 pmLambert-St Louis
United Airlines
Jul 29
STL5:30 pmLambert-St Louis
29h 18m
2 stops
ONT8:48 pmOntario
Aug 4
ONT6:00 amOntario
8h 28m
1 stop
STL4:28 pmLambert-St Louis

Frontier flights from St. Louis to Ontario

Our best Frontier deals on St. Louis to Ontario flight tickets
Frontier
Aug 28
STL8:00 pmLambert-St Louis
5h 39m
1 stop
ONT11:39 pmOntario
Sep 9
ONT12:49 amOntario
9h 01m
1 stop
STL11:50 amLambert-St Louis
Frontier
Aug 31
STL8:00 pmLambert-St Louis
5h 44m
1 stop
ONT11:44 pmOntario
Sep 17
ONT8:35 pmOntario
11h 43m
1 stop
STL10:18 amLambert-St Louis
Frontier
Aug 29
STL7:29 pmLambert-St Louis
19h 32m
1 stop
ONT1:01 pmOntario
Sep 2
ONT5:30 pmOntario
14h 48m
1 stop
STL10:18 amLambert-St Louis

How to get the cheapest flight ticket from St. Louis to Ontario

Look no further. We've gone through all the searches for this route on momondo so you have the important information and insights to find the cheapest flight ticket for your trip

What is the cheapest month to fly from St. Louis to Ontario?

April. The cheapest time of year to fly to Ontario from St. Louis is April. Most expensive is December

What is the cheapest day to depart St. Louis for Ontario?

Thursday. The cheapest day of the week is typically Thursday. The most expensive is typically Friday

When is the cheapest time to fly from St. Louis to Ontario?

In the evening. St. Louis to Ontario flights are approximately 57% more expensive at noon than in the evening

What is the cheapest airline that flies to Ontario from St. Louis?

Frontier. American Airlines, Delta, and Frontier are the most popular carriers operating from St. Louis to Ontario

What is the cheapest St. Louis to Ontario flight route?

Lambert-St Louis - Ontario. Fly from Lambert-St Louis to Ontario for the best St. Louis - Ontario flight prices

How far in advance should you book St. Louis to Ontario flights?

37 days before. The cheapest time to buy a flight from St. Louis to Ontario is approximately 37 days to departure

Cheap St. Louis to Ontario (STL to ONT) flight deals and tips

Find info about flight duration, direct flights, and airports for your flight from St. Louis to Ontario

Best Price Found

$74

Fastest flight time

5h 37m

Direct flights

None

Airports in Ontario

1 airport
The best one-way flight to Ontario from St. Louis in the past 72 hours is $74. The best round-trip flight deal from St. Louis to Ontario found on momondo in the last 72 hours is $136.
The fastest flight from St. Louis to Ontario takes 5h 37m
There are no direct flights from St. Louis to Ontario. Popular non-direct route for this connection is Lambert-St Louis Airport - Ontario Airport.
There is 1 airport near Ontario: Ontario (ONT)

  • How far is Lambert-St Louis to Ontario by plane?

    A flight from Lambert-St Louis to Ontario will travel around 1552.8 mi. 5h 37m is a normal flight duration for this route.

  • When did momondo last update prices for flights from Lambert-St Louis Airport to Ontario Airport?

    Prices for flights from Lambert-St Louis Airport to Ontario Airport are refreshed on a daily basis.

  • How many operators does momondo search for flights from Lambert-St Louis Airport to Ontario Airport?

  • How old do you have to be to fly from Lambert-St Louis Airport to Ontario Airport?

    The minimum age a child must be to fly alone is five but airlines that offer an unaccompanied minor (UNMR) service will have their own age restrictions, including rules around flight length, timings, and stopovers. We always recommend checking with the individual airline you are booking with to travel from Lambert-St Louis Airport to Ontario Airport.

  • What documentation or ID do you need to fly to Ontario Airport?

    The required travel and health documents for your Ontario Airport trip may vary depending on your itinerary and personal circumstances. As a general rule, you should carry multiple documents, including a national ID card or driver's license and a passport valid for six months after your intended arrival at Ontario Airport. We recommend that you seek guidance from your airline or a reliable third party such as IATA.


Best airlines flying from St. Louis to Ontario

Compare and see reviews for airlines that fly from St. Louis to Ontario with momondo
Airline
Rating
Free Cancellation
Price
FrontierPriceFrom $123Free CancellationRating
6.2
4,006 reviews
Search Frontier flights
DeltaPriceFrom $286Free CancellationRating
8.0
10,410 reviews
Search Delta flights
American AirlinesPriceFrom $309Free CancellationRating
7.3
14,260 reviews
Search American Airlines flights
United AirlinesPriceFrom $337Free CancellationRating
7.4
10,755 reviews
Search United Airlines flights

Why use momondo?

Why should I use momondo to find a flight deal from St. Louis to Ontario?

Finding the right flight to Ontario from St. Louis is quick and easy when you have a range of options in front of you, from reputable agents and recognisable airlines. Options that can then be filtered down to find the best fit. That is what momondo does. We make finding flights to Ontario quick and easy, saving you time and money.

Can I find flights from St. Louis to Ontario with flexible booking policies on momondo?

Yes. momondo enables you to select and highlight flights to Ontario from St. Louis with this policy.

How can momondo help me find flights from St. Louis to Ontario?

momondo helps you find the best flight between St. Louis and Ontario by providing filters to narrow your choice of flights to those matching your criteria. You can select flights based on numerous factors such as price, departure and landing times, airport and airline.

I’m not ready to book a flight from St. Louis to Ontario right now. Can momondo alert me if prices change?

If you are simply researching potential flights to Ontario, momondo offers a useful price alert feature which will track prices for flights to Ontario from St. Louis and alert you when they change.


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