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Cheap flights from St. Louis to Ottawa from $257

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 Ottawa departing on 7/1. Fares may change, and may not be available for all flights or travel dates. Click the price to refresh the search for this deal.
1 adult
0 bags

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Find the cheapest flights from St. Louis to Ottawa

Cheap round-trip flights

Enter your travel dates to find the best prices.
Air Canada Logo
1:00 pm - 8:51 pm
STL
-
YOW
6h 51m
1 stop
Air Canada Logo
2:25 pm - 8:05 pm
YOW
-
STL
6h 40m
1 stop
$410Air Canada
Thu, May 28 - Sat, May 30
Air Canada Logo
1:00 pm - 8:51 pm
STL
-
YOW
6h 51m
1 stop
Air Canada Logo
7:00 am - 12:06 pm
YOW
-
STL
6h 06m
1 stop
$419Air Canada
Mon, Jun 8 - Sun, Jun 14
Delta Logo
6:45 am - 5:35 pm
STL
-
YOW
9h 50m
2 stops
Delta Logo
5:55 am - 4:45 pm
YOW
-
STL
11h 50m
2 stops
$508Delta
Thu, May 28 - Sat, May 30
American Airlines Logo
6:20 am - 8:00 pm
STL
-
YOW
12h 40m
2 stops
American Airlines Logo
8:40 am - 9:01 pm
YOW
-
STL
13h 21m
2 stops
$578American Airlines
Fri, Jul 17 - Mon, Jul 20
United Airlines Logo
6:40 am - 6:42 pm
STL
-
YOW
11h 02m
2 stops
United Airlines Logo
5:25 pm - 10:44 pm
YOW
-
STL
6h 19m
1 stop
$583United Airlines
Thu, May 28 - Sat, May 30
Air Canada Logo
12:10 pm - 7:45 pm
STL
-
YOW
6h 35m
1 stop
Air Canada Logo
6:00 am - 6:27 pm
YOW
-
STL
13h 27m
1 stop
$596Air Canada
Sat, Jul 4 - Sun, Jul 19
WestJet Logo
6:00 am - 12:20 am
STL
-
YOW
17h 20m
2 stops
WestJet Logo
12:25 pm - 11:01 pm
YOW
-
STL
35h 36m
2 stops
$662WestJet
Mon, Jun 8 - Sun, Jun 14
American Airlines Logo
5:23 am - 8:00 pm
STL
-
YOW
13h 37m
3 stops
American Airlines Logo
8:40 am - 8:26 pm
YOW
-
STL
12h 46m
2 stops
$710American Airlines
Thu, May 28 - Sat, May 30
Air Canada Logo
12:10 pm - 7:45 pm
STL
-
YOW
6h 35m
1 stop
Air Canada Logo
2:25 pm - 6:27 pm
YOW
-
STL
5h 02m
1 stop
$721Air Canada
Fri, Jul 17 - Mon, Jul 20
United Airlines Logo
1:27 pm - 9:56 pm
STL
-
YOW
7h 29m
2 stops
United Airlines Logo
5:15 am - 2:18 pm
YOW
-
STL
10h 03m
2 stops
$745United Airlines
Sat, Jul 4 - Sun, Jul 19

WestJet flights from St. Louis to Ottawa

Our best WestJet deals on St. Louis to Ottawa flight tickets
WestJet
Jun 8
STL6:00 amLambert-St Louis
17h 20m
2 stops
YOW12:20 amOttawa
Jun 14
YOW12:25 pmOttawa
35h 36m
2 stops
STL11:01 pmLambert-St Louis
$662
WestJet
Feb 2
STL1:18 pmLambert-St Louis
10h 21m
2 stops
YOW12:39 amOttawa
Feb 6
YOW5:40 amOttawa
12h 02m
2 stops
STL4:42 pmLambert-St Louis
$1,569

Air Canada flights from St. Louis to Ottawa

Our best Air Canada deals on St. Louis to Ottawa flight tickets
Air Canada
May 28
STL1:00 pmLambert-St Louis
6h 51m
1 stop
YOW8:51 pmOttawa
May 30
YOW2:25 pmOttawa
6h 40m
1 stop
STL8:05 pmLambert-St Louis
$410
Air Canada
Jun 8
STL1:00 pmLambert-St Louis
6h 51m
1 stop
YOW8:51 pmOttawa
Jun 14
YOW7:00 amOttawa
6h 06m
1 stop
STL12:06 pmLambert-St Louis
$419
Air Canada
Jul 4
STL12:10 pmLambert-St Louis
6h 35m
1 stop
YOW7:45 pmOttawa
Jul 19
YOW6:00 amOttawa
13h 27m
1 stop
STL6:27 pmLambert-St Louis
$596

momondo Fare Finder

 
Customize your flight search to find flights from St. Louis to Ottawa 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, momondo users made 832,500 searches. Data last updated January 29, 2026.
Use the filters below to find and compare flights from St. Louis to Ottawa that are best for you.

Fly from

Fly to

Route

Depart

Return

Price

St. LouisOttawa

STL - YOW

STLYOW

Lambert-St Louis

Thu 5/28

1:00 pm-8:51 pm

1 stop6h 51m

Ottawa

Sat 5/30

2:25 pm-8:05 pm

1 stop6h 40m

$410

St. LouisOttawa

STL - YOW

STLYOW

Lambert-St Louis

Mon 6/8

1:00 pm-8:51 pm

1 stop6h 51m

Ottawa

Sun 6/14

7:00 am-12:06 pm

1 stop6h 06m

$419

St. LouisOttawa

STL - YOW

STLYOW

Lambert-St Louis

Thu 5/28

6:45 am-5:35 pm

2 stops9h 50m

Ottawa

Sat 5/30

5:55 am-4:45 pm

2 stops11h 50m

$508

St. LouisOttawa

STL - YOW

STLYOW

Lambert-St Louis

Fri 7/17

6:20 am-8:00 pm

2 stops12h 40m

Ottawa

Mon 7/20

8:40 am-9:01 pm

2 stops13h 21m

$578

St. LouisOttawa

STL - YOW

STLYOW

Lambert-St Louis

Thu 5/28

6:40 am-6:42 pm

2 stops11h 02m

Ottawa

Sat 5/30

5:25 pm-10:44 pm

1 stop6h 19m

$583

St. LouisOttawa

STL - YOW

STLYOW

Lambert-St Louis

Sat 7/4

12:10 pm-7:45 pm

1 stop6h 35m

Ottawa

Sun 7/19

6:00 am-6:27 pm

1 stop13h 27m

$596

St. LouisOttawa

STL - YOW

STLYOW

Lambert-St Louis

Mon 6/8

6:00 am-12:20 am

2 stops17h 20m

Ottawa

Sun 6/14

12:25 pm-11:01 pm

2 stops35h 36m

$662

St. LouisOttawa

STL - YOW

STLYOW

Lambert-St Louis

Thu 5/28

5:23 am-8:00 pm

3 stops13h 37m

Ottawa

Sat 5/30

8:40 am-8:26 pm

2 stops12h 46m

$710

St. LouisOttawa

STL - YOW

STLYOW

Lambert-St Louis

Fri 7/17

12:10 pm-7:45 pm

1 stop6h 35m

Ottawa

Mon 7/20

2:25 pm-6:27 pm

1 stop5h 02m

$721

St. LouisOttawa

STL - YOW

STLYOW

Lambert-St Louis

Sat 7/4

1:27 pm-9:56 pm

2 stops7h 29m

Ottawa

Sun 7/19

5:15 am-2:18 pm

2 stops10h 03m

$745

Flights are sorted by cheapest round-trip flights first.

Showing 1-10 of 13 resultsSorted by cheapest first
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How to get the cheapest flight ticket from St. Louis to Ottawa

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

Can stopping save me money on St. Louis to Ottawa flights?

You could potentially save up to 22% on your flight if you consider stops on a St. Louis to Ottawa flight.

When to book flights from St. Louis to Ottawa

Are you open to changing your travel dates? Check out the ideal times to fly from St. Louis to Ottawa according to our flight data. Find out which month and days have the cheapest flights.
Estimated round-trip price

Cheap St. Louis to Ottawa (STL to YOW) flight deals and tips

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

Fastest flight time

5h 59m

Direct flights

None
The fastest flight from St. Louis to Ottawa takes 5h 59m
There are no direct flights from St. Louis to Ottawa. There are no popular flight routes from St. Louis to Ottawa.
Search flight deals

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

    There are 877.2 mi between Lambert-St Louis and Ottawa. By plane, this route typically takes 5h 59m.

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

    Prices for flights from Lambert-St Louis Airport to Ottawa Airport are updated daily.

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

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

    The minimum age for a child to fly alone is five, but airlines offering an unaccompanied minor (UNMR) service may have their age restrictions, such as regulations concerning flight duration, timing, and layovers. It is recommended that you verify with the airline you are booking with for travel from Lambert-St Louis Airport to Ottawa Airport.

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

    The required travel and health documents for your Ottawa 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 Ottawa Airport. We recommend that you seek guidance from your airline or a reliable third party such as IATA.

  • What is the most popular airline from St. Louis to Ottawa?

Best airlines flying from St. Louis to Ottawa

Compare and see reviews for airlines that fly from St. Louis to Ottawa with momondo
Airline
Rating
Free Cancellation
Price
Air CanadaPriceFrom $139Free CancellationRating
7.1
10,667 reviews
Search Air Canada flights
United AirlinesPriceFrom $362Free CancellationRating
7.4
9,215 reviews
Search United Airlines flights

Traveling to a place near Ottawa?

Book flights to Ottawa if you plan to visit one of these locations
Gatineau
Pembroke
Calabogie
Brockville
Petawawa
Smiths Falls
Perth
Prescott
Winchester
Wakefield

Why use momondo?

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

momondo compares prices from hundreds of airlines and agents so you can find and book the best deal on flights from St. Louis to Ottawa. Millions of users trust and use momondo every year so you are in good hands.

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

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

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

momondo provides multiple filters to help you find the best flight to Ottawa from St. Louis. Filter by price, airline, airports, cabin, aircraft, payment method, number of stops and more.

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

Yes momondo offers price alerts on flights to Ottawa from St. Louis. After performing a search on this page you should be able to see the price alert set up feature. Simply provide a valid email address and momondo will instantly alert you when prices change.

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