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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 February, booked 36 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, 19% potential price rise

Cheapest in

September

Best time to find cheap flights, 33% potential price drop

Round-trip from

$232

From Ontario to Lambert-St Louis Intl

One-way from

$205

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 27% 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 $164 1-2 weeks out and tickets from $181 for flights departing within the next 72 hours.

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 October, November 2020

The best prices found for ONT to STL flights for October, November
2 Nov - 19 Nov
$152pp
ONT
Ontario
Frontier
 
1 STOP
STL
Lambert-St Louis
STL
Lambert-St Louis
Frontier
 
1 STOP
ONT
Ontario
4 Nov - 8 Nov
$155pp
ONT
Ontario
Frontier
 
1 STOP
STL
Lambert-St Louis
STL
Lambert-St Louis
Frontier
 
1 STOP
ONT
Ontario
2 Nov - 8 Nov
$158pp
ONT
Ontario
Frontier
 
1 STOP
STL
Lambert-St Louis
STL
Lambert-St Louis
Frontier
 
1 STOP
ONT
Ontario

Ontario to Lambert-St Louis Intl 2020 flight deals

Cheap flights to Lambert-St Louis Intl from Ontario found for this year
2 Nov - 19 Nov
$152pp
ONT
Ontario
Frontier
 
1 STOP
STL
Lambert-St Louis
STL
Lambert-St Louis
Frontier
 
1 STOP
ONT
Ontario
4 Nov - 8 Nov
$155pp
ONT
Ontario
Frontier
 
1 STOP
STL
Lambert-St Louis
STL
Lambert-St Louis
Frontier
 
1 STOP
ONT
Ontario
2 Nov - 8 Nov
$158pp
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
31 Oct - 6 Nov
$192pp
ONT
Ontario
Multiple Airlines
 
1 STOP
STL
Lambert-St Louis
STL
Lambert-St Louis
Alaska Airlines
 
1 STOP
ONT
Ontario
26 Oct - 29 Oct
$208pp
ONT
Ontario
Frontier
 
1 STOP
STL
Lambert-St Louis
STL
Lambert-St Louis
Frontier
 
1 STOP
ONT
Ontario
31 Oct - 6 Nov
$226pp
ONT
Ontario
Multiple Airlines
 
1 STOP
STL
Lambert-St Louis
STL
Lambert-St Louis
Alaska Airlines
   
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
3:52 am - 4:02 am
Frontier
1 Stop
22h 10m
ONT - STL
Frontier
$205
FlyFar
5:15 am - 5:45 am
Delta
3 Stops
22h 30m
ONT - STL
Delta
$748
Delta
12:25 pm - 9:03 am
Multiple Airlines
3 Stops
18h 38m
ONT - STL
Multiple Airlines
$752
mytrip.com

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 $152, but on average you can expect to pay $203.

Are there nonstop flights from Ontario to Lambert-St Louis Intl for under $200 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 $200?

There are currently 10+ open flights from Ontario to Lambert-St Louis Intl within the next 7 days for less than $200.

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 5 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 5h 41m. This flight may include one or multiple stops.

What are the cheapest airlines flying from Ontario to Lambert-St Louis Intl round-trip?

According to our current data, Frontier ($152), United Airlines ($232), and American Airlines ($247) 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 55% less than the average price by searching for these airlines.

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 $135. Users have also found prices from $143 and $174 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 October in Lambert-St Louis Intl
71.6 °F
Avg rainfall for October in Lambert-St Louis Intl
2.8 ″

Airports servicing Ontario

Airports servicing St. Louis

Hourly flight availability from Ontario to Lambert-St Louis Intl

Afternoon Noon to 6 PM 100% of ONT to STL departures
Early morning Midnight to 6 AM 0% of ONT to STL departures
Morning 6 AM to noon 0% of ONT to STL departures
Evening 6 PM to midnight 0% of ONT to STL departures
Midnight
6 AM
Noon
6 PM
Weekly flight availability
from Ontario to Lambert-St Louis Intl
Sunday
1 daily flight
Monday
1 daily flight
Tuesday
1 daily flight
Wednesday
1 daily flight
Thursday
1 daily flight
Friday
1 daily flight
Saturday
1 daily flight
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