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Cheap flights from Ontario to St. Louis (ONT - STL) from $75

This is the cheapest one-way flight price found by a Cheapflights user in the last 72 hours by searching for a flight departing on 6/9. 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.
ONT — STL
Jun 8 — Jun 151
From?
To?
Sat 6/8
Sat 6/15
1 adult, Economy
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The best prices from Ontario to Lambert-St Louis are usually found in October or November, booked 36 days in advance, depart on a Saturday or Wednesday and return on a Thursday

Cheap flight deals from Ontario to St. Louis

Discover tips and strategies to find the most affordable flight options for your journey from Ontario (ONT) to St. Louis (STL). Learn about various techniques such as flexible date searches, comparing prices across and setting up price alerts. Use these methods to find the cheapest flights available for your travel needs. Data last updated June 3, 2024.

Popular in

December

Cheapest in

October

Round-trip from

$319

One-way from

$203
High demand for flights, 39% potential price rise
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Best time to find cheap flights, 29% potential price drop
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From Ontario to Lambert-St Louis
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One-way flight from Ontario to Lambert-St Louis
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What is the cheapest day to fly round-trip from Ontario to St. Louis?

Leaving on a Friday is a viable option for saving on travel. Heavily demanded days of the week can typically drive up the prices you see. Booking your travel for a less competitive day can save up to 91% on the overall cost on flights from Ontario to St. Louis.

How far in advance should I book a flight from Ontario to St. Louis?

Users have found that booking a flight from Ontario to St. Louis at least 48 days early can save you up to 128% on average compared to booking a flight this week. If booking 48 days before your flight isn’t an option for you, users have found flights from Ontario to St. Louis for as little as $480 when booking for a departure date within the next two weeks. You can also check prices now. Some users have found airline tickets as low as $628 for flights departing within the next 3 days.

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

The best pricing can be found in the month of January. Prices to St. Louis from Ontario average $415. You can even find prices in January for less than $415, as users have found deals to St. Louis from as low as $215. The month of July appears to be one of the more expensive times to travel to St. Louis from Ontario. Flying in the targeted month can save you up to 12%.

What is the cheapest time of day to fly from ONT to STL?

A simple way to save on the total cost of your ticket is to fly from Ontario to St. Louis in the evening. If you’re flexible enough to do this you can expect to save up to 46% on your trip compared to booking a flight at noon.

Cheap American Airlines flights from Ontario to St. Louis

Explore cheap flight options specifically provided by American Airlines for the route between Ontario and St. Louis. Find affordable fares and compare prices with other airlines to secure the best deal for your journey. Over the last 7 days, Cheapflights users made 2,807,690 searches. Data last updated June 3, 2024.
Peruse some of the lowest-priced American Airlines flights we've found from Ontario to St. Louis. Come back soon if you're not finding the exact deal you're looking for.
Sat 8/318:10 amONT - STL
1 stop8h 29mAmerican Airlines
Sun 9/14:18 pmSTL - ONT
2 stops7h 22mAmerican Airlines
Deal found 6/3$365
Mon 6/244:36 pmONT - STL
1 stop5h 14mAmerican Airlines
Sun 8/258:04 amSTL - ONT
1 stop5h 43mAmerican Airlines
Deal found 6/2$417
Mon 6/2411:59 pmONT - STL
1 stop6h 55mAmerican Airlines
Sun 8/255:00 amSTL - ONT
2 stops8h 53mAmerican Airlines
Deal found 6/2$422
Sat 8/316:40 amONT - STL
2 stops14h 02mAmerican Airlines
Sun 9/14:18 pmSTL - ONT
2 stops7h 22mAmerican Airlines
Deal found 6/3$448
Fri 10/2511:00 pmONT - STL
1 stop9h 04mAmerican Airlines
Sun 10/275:36 amSTL - ONT
1 stop8h 04mAmerican Airlines
Deal found 6/2$456
Tue 10/19:41 amONT - STL
2 stops10h 28mAmerican Airlines
Sun 10/135:54 amSTL - ONT
1 stop5h 42mAmerican Airlines
Deal found 6/2$457
Tue 6/184:36 pmONT - STL
1 stop5h 14mAmerican Airlines
Wed 6/199:44 amSTL - ONT
2 stops8h 07mAmerican Airlines
Deal found 6/2$521
Mon 6/107:26 pmONT - STL
2 stops15h 46mAmerican Airlines
Tue 6/116:08 pmSTL - ONT
2 stops16h 39mAmerican Airlines
Deal found 6/2$705
Sat 6/89:24 amONT - STL
2 stops8h 52mAmerican Airlines
Sun 6/97:00 amSTL - ONT
1 stop8h 48mAmerican Airlines
Deal found 6/2$781

Cheap Frontier flights from Ontario to St. Louis

Explore cheap flight options specifically provided by Frontier for the route between Ontario and St. Louis. Find affordable fares and compare prices with other airlines to secure the best deal for your journey. Over the last 7 days, Cheapflights users made 2,807,690 searches. Data last updated June 3, 2024.
Browse through some of the cheapest Frontier flights traveling from Ontario to St. Louis. Deals frequently update to provide users with more options.
Fri 9/612:49 amONT - STL
1 stop6h 48mFrontier
Wed 9/118:00 pmSTL - ONT
1 stop5h 39mFrontier
Deal found 6/3$140
Mon 9/212:51 pmONT - STL
1 stop19h 27mFrontier
Tue 9/37:29 pmSTL - ONT
1 stop24h 40mFrontier
Deal found 6/2$144
Fri 8/3012:49 amONT - STL
1 stop6h 48mFrontier
Thu 9/57:29 pmSTL - ONT
1 stop19h 32mFrontier
Deal found 6/2$150
Fri 9/138:27 pmONT - STL
1 stop11h 10mFrontier
Mon 9/167:29 pmSTL - ONT
1 stop24h 40mFrontier
Deal found 6/2$153
Sun 6/912:59 amONT - STL
1 stop6h 30mFrontier
Tue 6/113:47 pmSTL - ONT
1 stop10h 12mFrontier
Deal found 6/2$163
Thu 9/1912:49 amONT - STL
1 stop6h 48mFrontier
Mon 9/238:00 pmSTL - ONT
1 stop5h 39mFrontier
Deal found 6/1$166
Thu 8/1512:49 amONT - STL
1 stop6h 48mFrontier
Tue 8/207:29 pmSTL - ONT
1 stop24h 40mFrontier
Deal found 6/2$168
Thu 6/1310:29 pmONT - STL
1 stop11h 25mFrontier
Thu 7/49:02 pmSTL - ONT
1 stop28h 38mFrontier
Deal found 6/2$169
Fri 8/168:27 pmONT - STL
1 stop11h 10mFrontier
Tue 8/2010:32 pmSTL - ONT
1 stop27h 07mFrontier
Deal found 6/2$170

Cheap Ontario to St. Louis flights in June & July 2024

Find cheap flight options from Ontario to St. Louis specifically for the months of June and July 2024. Explore affordable fares based on user searches. Over the last 7 days, Cheapflights users made 2,807,690 searches. Prices were last updated on June 3, 2024.
These are some of the most attractive deals on flights from Ontario to St. Louis in 2024. More deals are always being added, so be sure to check back regularly.
Thu 6/67:33 pmONT - STL
2 stops24h 26mFrontier
Sat 6/87:29 pmSTL - ONT
1 stop13h 34mFrontier
Deal found 6/2$155
Sun 6/912:59 amONT - STL
1 stop6h 30mFrontier
Tue 6/113:47 pmSTL - ONT
1 stop10h 12mFrontier
Deal found 6/2$163
Thu 6/1310:29 pmONT - STL
1 stop11h 25mFrontier
Thu 7/49:02 pmSTL - ONT
1 stop28h 38mFrontier
Deal found 6/2$169
Sun 6/97:23 pmONT - STL
2 stops24h 36mFrontier
Wed 6/128:02 pmSTL - ONT
1 stop5h 47mFrontier
Deal found 6/2$171
Thu 6/1310:29 pmONT - STL
1 stop11h 25mFrontier
Tue 6/187:29 pmSTL - ONT
1 stop15h 35mFrontier
Deal found 6/2$173
Thu 6/2712:44 amONT - STL
1 stop6h 56mFrontier
Sat 7/138:02 pmSTL - ONT
1 stop5h 54mFrontier
Deal found 6/2$197
Fri 6/2810:23 pmONT - STL
1 stop9h 06mFrontier
Sat 7/138:02 pmSTL - ONT
1 stop5h 54mFrontier
Deal found 6/2$198
Fri 6/78:50 pmONT - STL
1 stop11h 52mFrontier
Mon 6/108:22 pmSTL - ONT
1 stop5h 37mFrontier
Deal found 6/2$199
Thu 6/2712:44 amONT - STL
1 stop6h 56mFrontier
Mon 7/18:22 pmSTL - ONT
1 stop5h 37mFrontier
Deal found 6/1$200

Ontario to St. Louis 2024 flight deals

Discover exclusive flight deals for travel between Ontario and St. Louis in 2024. Find excellent offers based on user searches. Over the last 7 days, Cheapflights users made 2,807,690 searches. Data last updated June 3, 2024.
These are some of the most attractive deals on flights from Ontario to St. Louis in 2024. More deals are always being added, so be sure to check back regularly.
Mon 9/212:49 amONT - STL
1 stop9h 01mFrontier
Tue 9/1010:32 pmSTL - ONT
1 stop27h 07mFrontier
Deal found 6/3$136
Fri 9/612:49 amONT - STL
1 stop6h 48mFrontier
Wed 9/118:00 pmSTL - ONT
1 stop5h 39mFrontier
Deal found 6/3$140
Mon 9/212:51 pmONT - STL
1 stop19h 27mFrontier
Tue 9/37:29 pmSTL - ONT
1 stop24h 40mFrontier
Deal found 6/2$144
Fri 8/3012:49 amONT - STL
1 stop6h 48mFrontier
Thu 9/57:29 pmSTL - ONT
1 stop19h 32mFrontier
Deal found 6/2$150
Fri 9/138:27 pmONT - STL
1 stop11h 10mFrontier
Mon 9/167:29 pmSTL - ONT
1 stop24h 40mFrontier
Deal found 6/2$153
Thu 6/67:33 pmONT - STL
2 stops24h 26mFrontier
Sat 6/87:29 pmSTL - ONT
1 stop13h 34mFrontier
Deal found 6/2$155
Sun 6/912:59 amONT - STL
1 stop6h 30mFrontier
Tue 6/113:47 pmSTL - ONT
1 stop10h 12mFrontier
Deal found 6/2$163
Thu 9/1912:49 amONT - STL
1 stop6h 48mFrontier
Mon 9/238:00 pmSTL - ONT
1 stop5h 39mFrontier
Deal found 6/1$166
Thu 8/1512:49 amONT - STL
1 stop6h 48mFrontier
Tue 8/207:29 pmSTL - ONT
1 stop24h 40mFrontier
Deal found 6/2$168

Ontario to St. Louis flights leaving soon

Find last-minute flight options from Ontario to St. Louis for spontaneous travel. Discover available flights and compare prices based on user searches. Secure great deals and offers for spontaneous trips with quick booking options. Over the last 7 days, Cheapflights users made 2,807,690 searches. Data last updated June 3, 2024.
Have a look at some of the flights available from Ontario to St. Louis departing last-minute. Tip: verify your flight details before completing your reservation.
Sun 6/912:59 amONT - STL
1 stop6h 30mFrontier
Tue 6/113:47 pmSTL - ONT
1 stop10h 12mFrontier
Deal found 6/2$163
Thu 6/1310:29 pmONT - STL
1 stop11h 25mFrontier
Thu 7/49:02 pmSTL - ONT
1 stop28h 38mFrontier
Deal found 6/2$169
Sun 6/97:23 pmONT - STL
2 stops24h 36mFrontier
Wed 6/128:02 pmSTL - ONT
1 stop5h 47mFrontier
Deal found 6/2$171
Thu 6/1310:29 pmONT - STL
1 stop11h 25mFrontier
Tue 6/187:29 pmSTL - ONT
1 stop15h 35mFrontier
Deal found 6/2$173
Sat 6/812:59 amONT - STL
1 stop11h 38mFrontier
Wed 6/128:02 pmSTL - ONT
1 stop5h 47mFrontier
Deal found 6/2$199
Thu 6/1312:59 amONT - STL
1 stop6h 41mFrontier
Mon 6/178:22 pmSTL - ONT
1 stop5h 37mFrontier
Deal found 6/2$200
Thu 6/1312:59 amONT - STL
1 stop6h 41mFrontier
Sat 6/227:29 pmSTL - ONT
1 stop13h 34mFrontier
Deal found 6/2$210
Sun 6/912:59 amONT - STL
1 stop6h 30mFrontier
Wed 6/128:02 pmSTL - ONT
1 stop5h 47mFrontier
Deal found 6/2$219
Mon 6/1012:55 pmONT - STL
1 stop19h 47mFrontier
Wed 6/128:02 pmSTL - ONT
1 stop5h 47mFrontier
Deal found 6/2$224

One-way flights to St. Louis from Ontario

Search for one-way flight options from Ontario to St. Louis. Find affordable one-way fares based on user searches. Compare prices and availability to plan your one-way journey according to your preferred dates and budget. Over the last 7 days, Cheapflights users made 2,807,690 searches. Data last updated June 3, 2024.
Users in need of a one-way flight from Ontario to St. Louis can choose from these deals. Users in need of a round-trip flight from Ontario to St. Louis instead should update the search form at the top of page.
Sun 6/912:59 amONT - STL
1 stop6h 30mFrontier
Deal found 6/2$75
Mon 6/1012:59 amONT - STL
1 stop11h 48mFrontier
Deal found 6/2$81
Sun 6/3012:59 amONT - STL
1 stop6h 30mFrontier
Deal found 6/2$100
Thu 6/2712:44 amONT - STL
1 stop6h 56mFrontier
Deal found 6/2$101
Fri 8/308:27 pmONT - STL
1 stop11h 10mFrontier
Deal found 6/2$104
Sat 6/2212:59 amONT - STL
1 stop11h 38mFrontier
Deal found 6/1$106
Sun 6/99:40 pmONT - STL
2 stops22h 19mFrontier
Deal found 6/2$107
Mon 7/224:31 pmONT - STL
1 stop27h 00mFrontier
Deal found 6/2$110
Mon 7/112:54 pmONT - STL
1 stop20h 20mFrontier
Deal found 6/2$111

Find flights from Ontario to St. Louis within your budget

Customize your flight search to find flights from Ontario to St. Louis that fit within your specific budget. Explore options based on user searches and filter the results based on your desired price range. Find flights that match your budget for a cost-effective journey. Over the last 7 days, Cheapflights users made 2,807,690 searches. Data last updated June 3, 2024.

Fly from

Any airport

Fly to

Any airport

Budget

$140 - $458

Route

Depart

Return

Price

OntarioLambert-St Louis

ONT - STL

ONTSTL

Ontario

Fri 9/6

1 stop6h 48m

Lambert-St Louis

Wed 9/11

1 stop5h 39m

$140

OntarioLambert-St Louis

ONT - STL

ONTSTL

Ontario

Mon 9/2

1 stop19h 27m

Lambert-St Louis

Tue 9/3

1 stop24h 40m

$144

OntarioLambert-St Louis

ONT - STL

ONTSTL

Ontario

Fri 8/30

1 stop6h 48m

Lambert-St Louis

Thu 9/5

1 stop19h 32m

$150

OntarioLambert-St Louis

ONT - STL

ONTSTL

Ontario

Fri 9/13

1 stop11h 10m

Lambert-St Louis

Mon 9/16

1 stop24h 40m

$153

OntarioLambert-St Louis

ONT - STL

ONTSTL

Ontario

Thu 9/19

1 stop6h 48m

Lambert-St Louis

Mon 9/23

1 stop5h 39m

$166

OntarioLambert-St Louis

ONT - STL

ONTSTL

Ontario

Sat 8/31

1 stop8h 29m

Lambert-St Louis

Sun 9/1

2 stops7h 22m

$365

OntarioLambert-St Louis

ONT - STL

ONTSTL

Ontario

Wed 7/10

2 stops14h 59m

Lambert-St Louis

Mon 7/15

1 stop7h 17m

$371

OntarioLambert-St Louis

ONT - STL

ONTSTL

Ontario

Thu 9/12

1 stop5h 36m

Lambert-St Louis

Tue 9/17

1 stop6h 20m

$372

OntarioLambert-St Louis

ONT - STL

ONTSTL

Ontario

Sat 9/14

1 stop5h 53m

Lambert-St Louis

Tue 9/17

1 stop5h 27m

$458

Flights are sorted by cheapest first

Deals found on 6/3

How far ahead should I book a flight from Ontario to St. Louis?

Use this chart to determine the optimal time to book a round-trip flight from Ontario to St. Louis. Price data was last updated on May 31, 2024.
The best time to book flights from Ontario to St. Louis is 36 days before your desired departure date. The cost of your flight will likely increase significantly if you book two weeks in advance of your flight.
Search Deals

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

Use this chart to determine the cheapest time to fly round-trip from Ontario to St. Louis. Price data was last updated on May 26, 2024.
Morning
Noon
Afternoon
Evening
All times are departure.
Travelers seeking maximum savings on their Ontario to St. Louis flight should consider departing on Wednesday evenings when fares are most often at their lowest. Tuesday at noon flights should be avoided if possible as fares are typically the most expensive at this time.
Search Deals

Best time to book a flight from Ontario to St. Louis

Have a flexible travel schedule? Discover the best time to fly to St. Louis from Ontario with our price prediction graph.
Estimated round-trip price
Rates are based on past data. Find the cheapest month and day to book your flight based on your travel requirements, then search for cheap deals.

Temperature and rainfall in St. Louis by month

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

STL

Temperature

32 - 80.6 °F

Reviews of airlines servicing St. Louis

Get insights into the airlines that provide service to St. Louis. Read reviews, discover amenities, and learn about the overall travel experience offered by airlines. Use this information to make informed decisions when choosing an airline for your flight to St. Louis. Reviews last updated June 3, 2024.
Read through reviews of airlines operating flights from Ontario to St. Louis, such as American Airlines, Frontier and Delta. In addition to providing an overall rating, users have also rated airlines in terms of entertainment options, comfort, food, crew/service, and boarding process.
Southwest
8.2
Very good
5,939 reviews
Check prices

Overall

8.2

Boarding

8.3

Comfort

8.1

Crew

8.7

Entertainment

7.8

Food

7.3

Reviews

1 / 10

My original flight was delayed so they found this flight for me so I could arrive at a reasonable time

Southwest
8.2
Very good
5,939 reviews
Southwest
8.2
Very good
5,939 reviews
Check prices

Overall

8.2

Boarding

8.3

Comfort

8.1

Crew

8.7

Entertainment

7.8

Food

7.3

Reviews

1 / 10

My original flight was delayed so they found this flight for me so I could arrive at a reasonable time

Alaska Airlines
8.1
Very good
9,197 reviews
Southwest
8.2
Very good
5,939 reviews
Check prices

Overall

8.2

Boarding

8.3

Comfort

8.1

Crew

8.7

Entertainment

7.8

Food

7.3

Reviews

1 / 10

My original flight was delayed so they found this flight for me so I could arrive at a reasonable time

Delta
8.0
Very good
10,402 reviews
Southwest
8.2
Very good
5,939 reviews
Check prices

Overall

8.2

Boarding

8.3

Comfort

8.1

Crew

8.7

Entertainment

7.8

Food

7.3

Reviews

1 / 10

My original flight was delayed so they found this flight for me so I could arrive at a reasonable time

United Airlines
7.4
Good
10,740 reviews
Southwest
8.2
Very good
5,939 reviews
Check prices

Overall

8.2

Boarding

8.3

Comfort

8.1

Crew

8.7

Entertainment

7.8

Food

7.3

Reviews

1 / 10

My original flight was delayed so they found this flight for me so I could arrive at a reasonable time

American Airlines
7.3
Good
14,241 reviews
Southwest
8.2
Very good
5,939 reviews
Check prices

Overall

8.2

Boarding

8.3

Comfort

8.1

Crew

8.7

Entertainment

7.8

Food

7.3

Reviews

1 / 10

My original flight was delayed so they found this flight for me so I could arrive at a reasonable time

Related info for your journey

Find useful and relevant information for your journey from Ontario to St. Louis. Access travel guides, tips, and recommendations to enhance your travel experience. Get information about local attractions, weather, transportation options, and more.

  • Can I find flights from Ontario to St. Louis for under $200 on Cheapflights?

    Yes, there are multiple flights from Ontario to St. Louis for under $200. The cheapest flight booked recently is on Frontier for just $140, but on average you can expect to pay $179.

  • Are there last-minute flights available from Ontario to St. Louis for under $200?

    There are currently 20+ open flights from Ontario to St. Louis within the next 7 days for less than $200.

  • What is the cheapest airline to fly from Ontario to St. Louis round-trip?

    Flying on Frontier is currently your cheapest option to St. Louis, with prices starting at $140. Frontier is priced at 59% lower than the current average price of a flight leaving 3 months from now.

  • What are the cheapest airlines to fly from Ontario to St. Louis one-way?

    The cheapest airlines for a one-way flight from Ontario to St. Louis are Frontier ($75), American Airlines ($203), and Southwest ($226).

  • What does ONT to STL mean?

    These are just IATA (International Air Transport Association) codes. They are used in aviation to identify and differentiate airports. That’s why a Ontario Airport to Lambert-St Louis Airport flight would often be abbreviated as a ONT to STL flight.

  • Can I find deals for flights from Ontario to St. Louis that include extra baggage allowance?

    The amount of baggage you can bring on your Ontario to St. Louis flight depends on the airline and the type of fare you've chosen. After entering your flight details, you'll be able to view the specific baggage policies for each deal in the search results. Keep in mind that certain deals may offer additional baggage allowance.

  • Can I find deals on flights from Ontario to St. Louis with specific airlines?

    Yes, Cheapflights allows you to browse and filter Ontario to St. Louis flight deals by airline. After entering your origin and destination, use the available filters to view flights offered by airlines.

  • Can I find deals for flights from Ontario to St. Louis that include hotel bookings?

    Yes. In addition to deals on Ontario to St. Louis flights, Cheapflights offers vacation packages that include both flights and hotel.

  • How can I find direct flights from Ontario to St. Louis?

    After entering your origin and destination, apply the non-stop filter on the search result page to find direct flights from Ontario to St. Louis.

  • Can I find deals for business class flights from Ontario to St. Louis?

    Yes. Cheapflights offers flight deals from Ontario to St. Louis by cabin class. In addition to browsing deals, you can also filter by cabin class on the search results page after making a search.

  • Can I find deals for flights from Ontario to St. Louis that allow pets onboard?

    Many airlines flying from Ontario to St. Louis offer the option to travel with pets. After selecting a flight deal, you can find more information about the airline's pet policy on their official website or by contacting the airline directly. Please note that additional fees and restrictions may apply.

  • Can I find deals on last-minute flights from Ontario to St. Louis?

    Yes, you can often find last-minute deals on Ontario to St. Louis flights on Cheapflights. However, these deals can vary and may not always be available. We recommend checking back frequently or signing up for price alerts for the most up-to-date deals.

  • How recently were the Ontario to St. Louis flight deals updated?

    The Ontario to St. Louis flight deals you see on this page were last updated on 6/3.

  • What are the most popular airlines that fly from Ontario to St. Louis?

    Before booking your flight from Ontario to St. Louis check out the most popular airlines for this route: American Airlines, Delta or Frontier.

  • What is the cheapest month to book a flight from Ontario to St. Louis?

    Currently, September is the cheapest month in which you can book a flight from Ontario to St. Louis (average of $319). Flying from Ontario to St. Louis in July is currently the most expensive (average of $366). There are several factors that can impact the price of a flight, so comparing airlines, departure airports and flight times can provide users with more options.

See more FAQs

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Alternative routes for Ontario to St. Louis
See prices for flight routes from nearby airports that may be better suited for you.

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Top 4 airlines flying from Ontario to St. Louis

Discover the top 4 airlines that operate flights from Ontario to St. Louis. Compare their services, reliability, and customer satisfaction ratings to choose the airline that best suits your travel preferences and needs. Over the last 7 days, Cheapflights users made 2,807,690 searches. Data last updated June 3, 2024.
AirlineCheapestAverageFlexibilityOn-time
FrontierCheapest$104Average$200FlexibilityNo cancel feeOn-time62%
Search Frontier flights
DeltaCheapest$276Average$379FlexibilityNo cancel feeOn-timeN/A
Search Delta flights
American AirlinesCheapest$282Average$467FlexibilityNo cancel feeOn-time71%
Search American Airlines flights
United AirlinesCheapest$318Average$452FlexibilityNo cancel feeOn-time69%
Search United Airlines flights
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Ontario to Stockholm flights

Search flights from Ontario to St. Louis by cabin class

Find flights from Ontario to St. Louis, based on your preferred cabin class, be it economy, premium economy, business, or first class.
First Class
Business Class
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Economy Class

Hourly flight availability from Ontario to St. Louis

Find hourly flight availability from Ontario to St. Louis. Discover flight options and departure times throughout the day, allowing you to choose a departure time that suits your schedule. Data last updated June 3, 2024.
0%of flight departuresEarly morningMidnight to 6 am
100%of flight departuresMorning6 am to noon
0%of flight departuresAfternoonNoon to 6 pm
0%of flight departuresEvening6 pm to midnight
Midnight
6 AM
Noon
6 PM

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Cheapflights makes it easy to find Ontario to St. Louis flights by helping our users search from 900+ travel sites for deals. We also provide you with filters for cabin, price, airline, airports, number of stops, and many more to narrow down that perfect flight.

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Can Cheapflights find flights from Ontario to St. Louis with no change fees?

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Can Cheapflights notify me if prices for flights from Ontario to St. Louis become cheaper?

Yes, Cheapflights offers price alerts on Ontario to St. Louis flights so you can book your travel at the perfect time. Price Alerts can be enabled by clicking the bell icon next to the flight deals above and providing your email address where you want to receive the alerts.

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