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Cheap flights from Ontario to Lambert-St Louis Intl (ONT - STL)

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The best prices from Ontario to Lambert-St Louis Intl are usually found in September or August, booked 41 days in advance, depart on a Tuesday or Wednesday and return on a Tuesday

How to find the cheapest flight from
Ontario (ONT) to Lambert-St Louis Intl (STL)

ONT - STL
Price
$232 - $428
STL
Temperature
44.6 - 89.6 °F
STL
Rainfall
2.2 - 5.1 inches

Popular in

December

High demand for flights, 22% potential price rise

Cheapest in

September

Best time to find cheap flights, 31% potential price drop

Round-trip from

$232

From Ontario to Lambert-St Louis Intl

One-way from

$153

One-way flight from Ontario to Lambert-St Louis Intl

Flight route prices based on searches on Cheapflights within the last 3 days, monthly prices based on aggregated historical data.
What is the cheapest day to fly round-trip from Ontario to Lambert-St Louis Intl?

Flights from Ontario to Lambert-St Louis Intl are found to be more expensive on Thursday. This shouldn't discourage you from searching as you can still find great deals by being flexible with your options. Use our search form to find deals on tickets to Lambert-St Louis Intl.

How far in advance should I book a flight from Ontario to Lambert-St Louis Intl?

To save up to 33% on this flight, we recommend booking at least 61 days prior to travel. The price may fluctuate and will likely increase closer to your departure date. Users on Cheapflights have found tickets from Ontario to Lambert-St Louis Intl from $143 1-2 weeks out and tickets from $179 for flights departing within the next 72 hours.

What is the cheapest month to fly from Ontario to Lambert-St Louis Intl?

The best pricing can be found in the month of June. Prices to Lambert-St Louis Intl from Ontario average $148. You can even find prices in June for less than $148, as users have found deals to Lambert-St Louis Intl from as low as $77. The month of July appears to be one of the more expensive times to travel to Lambert-St Louis Intl from Ontario. Flying in the targeted month can save you up to 34%.

When is the cheapest time to fly from Ontario to Lambert-St Louis Intl (ONT - STL)?

It’s optimal to fly from Ontario to Lambert-St Louis Intl in the afternoon. By choosing this option you can save up to 32% on the cost of your flight, compared to a flight in the morning.

Cheap flights from Ontario to Lambert-St Louis Intl in January, February 2021

The best prices found for ONT to STL flights for January, February
19 Feb - 21 Feb
$122pp
ONT
Ontario
Frontier
 
1 STOP
STL
Lambert-St Louis
STL
Lambert-St Louis
Frontier
 
1 STOP
ONT
Ontario
26 Feb - 10 Mar
$129pp
ONT
Ontario
Frontier
 
1 STOP
STL
Lambert-St Louis
STL
Lambert-St Louis
Frontier
 
1 STOP
ONT
Ontario
4 Feb - 18 Feb
$134pp
ONT
Ontario
Frontier
 
1 STOP
STL
Lambert-St Louis
STL
Lambert-St Louis
Frontier
 
1 STOP
ONT
Ontario

Ontario to Lambert-St Louis Intl 2021 flight deals

Cheap flights to Lambert-St Louis Intl from Ontario found for this year
19 Feb - 21 Feb
$122pp
ONT
Ontario
Frontier
 
1 STOP
STL
Lambert-St Louis
STL
Lambert-St Louis
Frontier
 
1 STOP
ONT
Ontario
26 Feb - 10 Mar
$129pp
ONT
Ontario
Frontier
 
1 STOP
STL
Lambert-St Louis
STL
Lambert-St Louis
Frontier
 
1 STOP
ONT
Ontario
4 Feb - 18 Feb
$134pp
ONT
Ontario
Frontier
 
1 STOP
STL
Lambert-St Louis
STL
Lambert-St Louis
Frontier
 
1 STOP
ONT
Ontario

Last minute flights from Ontario to Lambert-St Louis Intl

Late deals on round-trip flights to Lambert-St Louis Intl from Ontario, departing today and this week
28 Jan - 31 Jan
$259pp
ONT
Ontario
Multiple Airlines
 
1 STOP
STL
Lambert-St Louis
STL
Lambert-St Louis
Multiple Airlines
     
3 STOPS
ONT
Ontario
28 Jan - 31 Jan
$290pp
ONT
Ontario
Multiple Airlines
 
1 STOP
STL
Lambert-St Louis
STL
Lambert-St Louis
United Airlines
 
1 STOP
ONT
Ontario
28 Jan - 31 Jan
$322pp
ONT
Ontario
Major Airline
 
1 STOP
STL
Lambert-St Louis
STL
Lambert-St Louis
Major Airline
   
2 STOPS
ONT
Ontario

One-way flights to Lambert-St Louis Intl from Ontario

The cheapest one-way flights from Ontario to Lambert-St Louis Intl
8:07 am - 7:43 pm
Frontier
1 Stop
9h 36m
ONT - STL
Frontier
6:30 am - 12:09 pm
Multiple Airlines
3 Stops
27h 39m
ONT - STL
Multiple Airlines
$265
United
8:29 pm - 7:44 am
American Airlines
2 Stops
9h 15m
ONT - STL
American Airlines

Related info for your journey

Useful info, stats and facts about Ontario to Lambert-St Louis Intl flights.

Flight FAQs

From Ontario to Lambert-St Louis Intl

Are flight prices decreasing from Ontario to St Louis due to COVID-19 (coronavirus)?

At this time, Cheapflights has noticed price decreases for many domestic flights due to COVID-19. Travel is not necessarily recommended at this time, and flights may be prone to cancellation: please check with local authorities in both Ontario and St Louis for travel alerts, and be sure to review the airline's cancellation policy and travel advisories before booking. For more information, please view our post on what to know about COVID-19 (coronavirus) and travel.

What safety measures are being taken by airlines flying from Ontario to Lambert-St Louis to control the spread of COVID-19?

Airlines globally have implemented additional safety measures to accommodate you. Delta is one of them. Some of the new policies that have been implemented to accommodate travelers flying from Ontario to Lambert-St Louis are improved sanitation, HEPA filters, mask requirements, social distance seating (for a limited time), and pre-flight testing for antibodies and symptoms. Policies will vary by airline.

Which airlines flying from Ontario to Lambert-St Louis have flexible cancellations due to COVID-19?

Some of the carriers operating flights from Ontario to Lambert-St Louis that may be offering flexible cancellation policies are American Airlines, Frontier, and United Airlines. Our site will let you filter for all airlines offering greater flexibility due to COVID-19.

Can I find flights from Ontario to Lambert-St Louis Intl for under $200 on Cheapflights?

Yes, there are multiple flights from Ontario to Lambert-St Louis Intl for under $200. The cheapest flight booked recently is on Frontier for just $122, but on average you can expect to pay $167.

Are there nonstop flights from Ontario to Lambert-St Louis Intl for under $100 on Cheapflights?

There are no nonstop flights from Ontario to Lambert-St Louis Intl, but Cheapflights can provide you with all the information you need to find the fastest route with the fewest stops.

Are there last-minute flights available from Ontario to Lambert-St Louis Intl for under $300?

There are currently 20+ open flights from Ontario to Lambert-St Louis Intl within the next 7 days for less than $300.

How popular is this flight route?

This flight path from Ontario to Lambert-St Louis was viewed by 283 users in the past month. Keep an eye out for changes in search interest prior to high and low season.

Does it rain more in Ontario or St Louis?

In Ontario, there will be less rainfall in Ontario compared to St Louis over the next 8 days.

Is Ontario weather warmer or cooler than St Louis?

We forecast the temperature to be around the 95 °F's in July, on average. The temperature in St Louis is generally colder than in Ontario. Book flights in a timely manner in correlation to your departure date.

How long is the flight from Ontario to Lambert-St Louis Intl?

Departing from Ontario to Lambert-St Louis Intl will take you 6h 56m.

What is the cheapest airline to fly from Ontario to Lambert-St Louis Intl round-trip?

According to our current data, Frontier ($122), offers the cheapest pricing from Ontario to Lambert-St Louis Intl. You may be able to fly from Ontario to Lambert-St Louis Intl for 63% less than the average price by searching for this airline.

What are the cheapest airlines to fly from Ontario to Lambert-St Louis Intl one-way?

For one-way options, check prices for Frontier. According to our data, you can fly for as low as $153. Users have also found prices from $242 and $244 on Frontier and United Airlines, respectively.

Alternative routes for Ontario to Lambert-St Louis Intl

Destination information for Lambert-St Louis Intl

Things to know before you go. Useful info for your trip from Ontario to Lambert-St Louis Intl
Average temperature for January in Lambert-St Louis Intl
44.6 °F
Avg rainfall for January in Lambert-St Louis Intl
2.8 ″

Airports servicing Ontario

Airports servicing St. Louis

Top 4 airlines flying from Ontario to Lambert-St Louis Intl

The chart below displays the airlines Cheapflights users traveling from Ontario to Lambert-St Louis Intl choose most often. Cheapest and average prices are based on aggregated data from the past 12 months.

Airline Cheapest Average Flexibility On-time COVID-19 safety
Frontier
$104 $241 No cancel fee 62%
Delta
$149 $333 No cancel fee N/A
United Airlines
$159 $397 No cancel fee 69%
American Airlines
$159 $416 No cancel fee 71%
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