Cheap flights from Ontario to St. Louis (ONT - STL) from $73
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 8/11. 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
May 14 — May 211
From?
To?
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 May 9, 2024.
Popular in | December |
|---|---|
Cheapest in | October |
Round-trip from | $322 |
One-way from | $202 |
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 2,717,708 searches. Data last updated May 9, 2024.
Peruse some of the lowest-priced Frontier flights we've found from Ontario to St. Louis. Come back soon if you're not finding the exact deal you're looking for.
Mon 5/2012:59 amONT - STL
1 stop10h 10mFrontier
Tue 5/287:23 pmSTL - ONT
1 stop22h 42mFrontier
Deal found 5/7$132
Tue 5/215:41 pmONT - STL
1 stop14h 32mFrontier
Wed 5/227:23 pmSTL - ONT
1 stop22h 39mFrontier
Deal found 5/8$136
Sun 5/266:09 pmONT - STL
1 stop14h 04mFrontier
Sat 6/17:23 pmSTL - ONT
1 stop16h 11mFrontier
Deal found 5/8$137
Thu 5/2311:07 pmONT - STL
1 stop9h 06mFrontier
Tue 5/282:12 pmSTL - ONT
1 stop27h 53mFrontier
Deal found 5/8$139
Tue 5/1412:39 pmONT - STL
1 stop7h 20mFrontier
Wed 5/154:39 pmSTL - ONT
1 stop7h 21mFrontier
Deal found 5/7$140
Fri 5/3112:59 amONT - STL
1 stop6h 26mFrontier
Fri 6/145:36 pmSTL - ONT
1 stop5h 47mFrontier
Deal found 5/7$143
Wed 6/128:03 amONT - STL
1 stop28h 29mFrontier
Sat 6/157:29 pmSTL - ONT
1 stop13h 34mFrontier
Deal found 5/7$144
Thu 8/1512:49 amONT - STL
1 stop6h 48mFrontier
Sun 8/183:53 pmSTL - ONT
1 stop9h 46mFrontier
Deal found 5/7$146
Fri 6/710:23 pmONT - STL
1 stop9h 06mFrontier
Sun 6/93:37 pmSTL - ONT
1 stop16h 46mFrontier
Deal found 5/8$147
Cheap Delta flights from Ontario to St. Louis
Explore cheap flight options specifically provided by Delta 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 2,717,708 searches. Data last updated May 9, 2024.
Browse through some of the cheapest Delta flights traveling from Ontario to St. Louis. Deals frequently update to provide users with more options.
Wed 6/511:22 amONT - STL
2 stops11h 34mDelta
Wed 6/126:25 pmSTL - ONT
1 stop7h 17mDelta
Deal found 5/8$378
Tue 6/115:00 pmONT - STL
1 stop5h 58mDelta
Sun 6/237:55 amSTL - ONT
1 stop6h 22mDelta
Deal found 5/7$445
Wed 5/156:50 amONT - STL
2 stops13h 02mDelta
Wed 5/225:30 pmSTL - ONT
1 stop8h 13mDelta
Deal found 5/9$576
Thu 5/1610:00 pmONT - STL
1 stop8h 54mDelta
Thu 5/237:55 amSTL - ONT
1 stop6h 18mDelta
Deal found 5/9$599
Wed 5/155:45 amONT - STL
1 stop5h 47mDelta
Wed 5/226:00 amSTL - ONT
1 stop7h 40mDelta
Deal found 5/9$648
Wed 5/156:50 amONT - STL
2 stops13h 02mDelta
Wed 5/225:30 pmSTL - ONT
1 stop8h 13mDelta
Deal found 5/8$656
Fri 6/215:35 amONT - STL
1 stop5h 59mDelta
Fri 6/216:25 pmSTL - ONT
1 stop7h 17mDelta
Deal found 5/8$672
Cheap Ontario to St. Louis flights in May & June 2024
Find cheap flight options from Ontario to St. Louis specifically for the months of May and June 2024. Explore affordable fares based on user searches. Over the last 7 days, Cheapflights users made 2,717,708 searches. Prices were last updated on May 9, 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 5/2012:59 amONT - STL
1 stop10h 10mFrontier
Tue 5/287:23 pmSTL - ONT
1 stop22h 42mFrontier
Deal found 5/7$132
Tue 5/215:41 pmONT - STL
1 stop14h 32mFrontier
Wed 5/227:23 pmSTL - ONT
1 stop22h 39mFrontier
Deal found 5/8$136
Sun 5/266:09 pmONT - STL
1 stop14h 04mFrontier
Sat 6/17:23 pmSTL - ONT
1 stop16h 11mFrontier
Deal found 5/8$137
Thu 5/2311:07 pmONT - STL
1 stop9h 06mFrontier
Tue 5/282:12 pmSTL - ONT
1 stop27h 53mFrontier
Deal found 5/8$139
Fri 6/710:23 pmONT - STL
1 stop9h 06mFrontier
Fri 6/145:36 pmSTL - ONT
1 stop5h 47mFrontier
Deal found 5/8$140
Fri 5/3112:59 amONT - STL
1 stop6h 26mFrontier
Fri 6/145:36 pmSTL - ONT
1 stop5h 47mFrontier
Deal found 5/7$143
Fri 6/78:50 pmONT - STL
1 stop11h 52mFrontier
Sat 6/157:29 pmSTL - ONT
1 stop13h 34mFrontier
Deal found 5/9$144
Wed 5/2912:59 amONT - STL
1 stop19h 07mFrontier
Sun 6/211:22 pmSTL - ONT
1 stop26h 37mFrontier
Deal found 5/9$145
Wed 5/1512:39 pmONT - STL
1 stop25h 32mFrontier
Thu 5/1611:06 pmSTL - ONT
1 stop26h 53mFrontier
Deal found 5/8$146
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 2,717,708 searches. Data last updated May 9, 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 5/2012:59 amONT - STL
1 stop10h 10mFrontier
Tue 5/287:23 pmSTL - ONT
1 stop22h 42mFrontier
Deal found 5/7$132
Tue 5/215:41 pmONT - STL
1 stop14h 32mFrontier
Wed 5/227:23 pmSTL - ONT
1 stop22h 39mFrontier
Deal found 5/8$136
Sun 5/266:09 pmONT - STL
1 stop14h 04mFrontier
Sat 6/17:23 pmSTL - ONT
1 stop16h 11mFrontier
Deal found 5/8$137
Thu 5/2311:07 pmONT - STL
1 stop9h 06mFrontier
Tue 5/282:12 pmSTL - ONT
1 stop27h 53mFrontier
Deal found 5/8$139
Fri 6/710:23 pmONT - STL
1 stop9h 06mFrontier
Fri 6/145:36 pmSTL - ONT
1 stop5h 47mFrontier
Deal found 5/8$140
Fri 5/3112:59 amONT - STL
1 stop6h 26mFrontier
Fri 6/145:36 pmSTL - ONT
1 stop5h 47mFrontier
Deal found 5/7$143
Fri 6/78:50 pmONT - STL
1 stop11h 52mFrontier
Sat 6/157:29 pmSTL - ONT
1 stop13h 34mFrontier
Deal found 5/9$144
Wed 5/2912:59 amONT - STL
1 stop19h 07mFrontier
Sun 6/211:22 pmSTL - ONT
1 stop26h 37mFrontier
Deal found 5/9$145
Wed 5/1512:39 pmONT - STL
1 stop25h 32mFrontier
Thu 5/1611:06 pmSTL - ONT
1 stop26h 53mFrontier
Deal found 5/8$146
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 2,717,708 searches. Data last updated May 9, 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.
Tue 5/1412:39 pmONT - STL
1 stop7h 20mFrontier
Wed 5/154:39 pmSTL - ONT
1 stop7h 21mFrontier
Deal found 5/7$140
Wed 5/1512:39 pmONT - STL
1 stop25h 32mFrontier
Thu 5/1611:06 pmSTL - ONT
1 stop26h 53mFrontier
Deal found 5/8$146
Sun 5/1911:30 pmONT - STL
1 stop8h 43mFrontier
Tue 5/217:23 pmSTL - ONT
1 stop15h 41mFrontier
Deal found 5/9$147
Fri 5/1711:04 pmONT - STL
1 stop9h 09mFrontier
Mon 5/207:23 pmSTL - ONT
1 stop23h 17mFrontier
Deal found 5/9$161
Fri 5/1711:04 pmONT - STL
1 stop9h 09mFrontier
Mon 5/207:23 pmSTL - ONT
1 stop23h 17mFrontier
Deal found 5/8$162
Sat 5/1812:59 amONT - STL
1 stop19h 33mFrontier
Tue 5/217:23 pmSTL - ONT
1 stop22h 42mFrontier
Deal found 5/9$166
Tue 5/1412:59 amONT - STL
1 stop6h 48mFrontier
Sat 5/188:04 pmSTL - ONT
1 stop5h 55mFrontier
Deal found 5/9$167
Tue 5/1412:59 amONT - STL
1 stop6h 48mFrontier
Thu 5/167:23 pmSTL - ONT
1 stop22h 16mFrontier
Deal found 5/8$168
Thu 5/1611:07 pmONT - STL
1 stop9h 06mFrontier
Sat 5/1811:41 pmSTL - ONT
1 stop8h 36mFrontier
Deal found 5/8$169
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 2,717,708 searches. Data last updated May 9, 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 8/1112:49 amONT - STL
1 stop6h 48mFrontier
Deal found 5/7$73
Sat 5/2510:10 pmONT - STL
1 stop10h 03mFrontier
Deal found 5/8$76
Mon 8/128:35 pmONT - STL
1 stop11h 43mFrontier
Deal found 5/7$83
Fri 9/2712:49 amONT - STL
1 stop6h 48mFrontier
Deal found 5/8$85
Wed 9/48:35 pmONT - STL
1 stop11h 43mFrontier
Deal found 5/8$91
Tue 9/312:49 amONT - STL
1 stop6h 48mFrontier
Deal found 5/8$99
Thu 8/112:49 amONT - STL
1 stop6h 48mFrontier
Deal found 5/8$100
Thu 5/161:15 pmONT - STL
1 stop6h 51mFrontier
Deal found 5/8$103
Tue 7/912:49 amONT - STL
1 stop6h 48mFrontier
Deal found 5/8$105
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 2,717,708 searches. Data last updated May 9, 2024.
Fly from
Any airport
Fly to
Any airport
Budget
$132 - $413
Route
Depart
Return
Price
OntarioLambert-St Louis
ONT - STL
ONTSTL
Ontario
Mon 5/20
1 stop10h 10m
Lambert-St Louis
Tue 5/28
1 stop22h 42m
$132
OntarioLambert-St Louis
ONT - STL
ONTSTL
Ontario
Tue 5/21
1 stop14h 32m
Lambert-St Louis
Wed 5/22
1 stop22h 39m
$136
OntarioLambert-St Louis
ONT - STL
ONTSTL
Ontario
Sun 5/26
1 stop14h 04m
Lambert-St Louis
Sat 6/1
1 stop16h 11m
$137
OntarioLambert-St Louis
ONT - STL
ONTSTL
Ontario
Thu 5/23
1 stop9h 06m
Lambert-St Louis
Tue 5/28
1 stop27h 53m
$139
OntarioLambert-St Louis
ONT - STL
ONTSTL
Ontario
Fri 6/7
1 stop9h 06m
Lambert-St Louis
Fri 6/14
1 stop5h 47m
$140
OntarioLambert-St Louis
ONT - STL
ONTSTL
Ontario
Fri 5/31
1 stop6h 26m
Lambert-St Louis
Fri 6/14
1 stop5h 47m
$143
OntarioLambert-St Louis
ONT - STL
ONTSTL
Ontario
Fri 9/27
2 stops8h 59m
Lambert-St Louis
Tue 10/8
1 stop9h 09m
$369
OntarioLambert-St Louis
ONT - STL
ONTSTL
Ontario
Wed 6/5
2 stops11h 34m
Lambert-St Louis
Wed 6/12
1 stop7h 17m
$378
OntarioLambert-St Louis
ONT - STL
ONTSTL
Ontario
Tue 6/11
1 stop6h 30m
Lambert-St Louis
Sat 6/15
2 stops11h 03m
$413
No data available for this route at this time. Please check back soon.
Average price of flights to St. Louis by month
Plan your trip from Ontario to St. Louis by taking into account the cheapest months to travel. The average price of a one-way flight from Ontario to St. Louis is currently $91 while a round-trip flight costs $221. Price data was last updated on May 5, 2024.
January
$326
February
$331
March
$357
April
$337
May
$342
June
$369
July
$372
August
$336
September
$322
October
$324
November
$336
December
$326
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 May 9, 2024.
Read through reviews of airlines operating flights from Ontario to St. Louis, such as Frontier, Delta and Alaska Airlines. In addition to providing an overall rating, users have also rated airlines in terms of entertainment options, comfort, food, crew/service, and boarding process.
9,142 reviews
Boarding
8.2
Overall
8.1
Comfort
7.9
Crew
8.6
Entertainment
7.3
Food
7.3
Reviews
1 / 10
Paid a lot for our exit row seats and they weren’t that roomy.
9,142 reviews
9,142 reviews
Boarding
8.2
Overall
8.1
Comfort
7.9
Crew
8.6
Entertainment
7.3
Food
7.3
Reviews
1 / 10
Paid a lot for our exit row seats and they weren’t that roomy.
10,778 reviews
9,142 reviews
Boarding
8.2
Overall
8.1
Comfort
7.9
Crew
8.6
Entertainment
7.3
Food
7.3
Reviews
1 / 10
Paid a lot for our exit row seats and they weren’t that roomy.
11,027 reviews
9,142 reviews
Boarding
8.2
Overall
8.1
Comfort
7.9
Crew
8.6
Entertainment
7.3
Food
7.3
Reviews
1 / 10
Paid a lot for our exit row seats and they weren’t that roomy.
14,665 reviews
9,142 reviews
Boarding
8.2
Overall
8.1
Comfort
7.9
Crew
8.6
Entertainment
7.3
Food
7.3
Reviews
1 / 10
Paid a lot for our exit row seats and they weren’t that roomy.
4,088 reviews
9,142 reviews
Boarding
8.2
Overall
8.1
Comfort
7.9
Crew
8.6
Entertainment
7.3
Food
7.3
Reviews
1 / 10
Paid a lot for our exit row seats and they weren’t that roomy.
Browse thousands of different options on Cheapflights for your next trip
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Alternative routes for Ontario to St. LouisSee prices for flight routes from nearby airports that may be better suited for you.
See prices for flight routes from nearby airports that may be better suited for you.
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 2,717,708 searches. Data last updated May 9, 2024.
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.
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 May 9, 2024.
| 0%of flight departures | Early morningMidnight to 6 am |
|---|---|
| 100%of flight departures | Morning6 am to noon |
| 0%of flight departures | AfternoonNoon to 6 pm |
| 0%of flight departures | Evening6 pm to midnight |
Midnight
6 AM
Noon
6 PM