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Cheap flights from Ottawa to Illinois from C$ 256

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 7/6. Fares are subject to change and may not be available on all flights or dates of travel.
YOW — ORD
30 May — 6 Jun1
1 adult
1 adult, Economy, 0 bags

Cheap flight deals from Ottawa to Illinois

Enter your travel dates to find the best prices.

Cheapest flights from Ottawa to Illinois
Explore the most affordable flight options available from Ottawa to Illinois. Find the lowest fares from popular airlines and budget airlines, with prices last updated on 30 April 2026.

Sat 23/52:40 p.m.
YOW
-
STL
1 stop6h 45m
Air Canada
Sun 24/57:05 a.m.
STL
-
YOW
1 stop5h 00m
Air Canada
Deal found 28/4C$ 430
Sat 23/55:50 p.m.
YOW
-
STL
1 stop6h 45m
United Airlines
Wed 27/56:00 a.m.
STL
-
YOW
1 stop9h 38m
United Airlines
Deal found 26/4C$ 438
Tue 2/610:44 a.m.
YOW
-
STL
1 stop11h 32m
United Airlines
Wed 3/66:00 a.m.
STL
-
YOW
1 stop9h 38m
United Airlines
Deal found 27/4C$ 439
Fri 12/67:00 a.m.
YOW
-
STL
1 stop6h 06m
Air Canada
Fri 19/62:15 p.m.
STL
-
YOW
1 stop6h 00m
Air Canada
Deal found 28/4C$ 449
Tue 19/57:00 a.m.
YOW
-
ORD
2 stops17h 13m
Multiple Airlines
Tue 26/55:30 p.m.
ORD
-
YOW
1 stop23h 30m
Multiple Airlines
Deal found 26/4C$ 483
Mon 25/510:10 a.m.
YOW
-
MDW
2 stops49h 59m
Multiple Airlines
Mon 1/610:15 a.m.
MDW
-
YOW
1 stop4h 44m
Multiple Airlines
Deal found 26/4C$ 516
Sun 14/611:00 a.m.
YOW
-
MDW
1 stop4h 35m
Porter Airlines
Sun 21/63:20 p.m.
MDW
-
YOW
1 stop3h 44m
Porter Airlines
Deal found 29/4C$ 520
Fri 24/75:10 a.m.
YOW
-
STL
2 stops8h 01m
United Airlines
Sat 8/89:23 a.m.
STL
-
YOW
1 stop11h 12m
United Airlines
Deal found 29/4C$ 534
Wed 20/57:20 a.m.
YOW
-
ORD
1 stop10h 20m
WestJet
Mon 25/55:30 p.m.
ORD
-
YOW
1 stop11h 05m
WestJet
Deal found 29/4C$ 535
Fri 12/65:05 a.m.
YOW
-
STL
2 stops11h 41m
United Airlines
Fri 19/62:15 p.m.
STL
-
YOW
1 stop6h 00m
United Airlines
Deal found 28/4C$ 536
Fri 12/68:00 a.m.
YOW
-
MDW
1 stop7h 35m
Porter Airlines
Fri 19/63:20 p.m.
MDW
-
YOW
1 stop3h 44m
Porter Airlines
Deal found 28/4C$ 547
Mon 1/67:00 a.m.
YOW
-
ORD
1 stop30h 37m
Multiple Airlines
Thu 4/612:59 p.m.
ORD
-
YOW
1 stop22h 18m
Multiple Airlines
Deal found 25/4C$ 547

Find flight deals from Ottawa to Illinois

Keep the following information in mind while searching for Ottawa to Illinois flight deals. Data was last updated 30 April 2026.

Round-trip from

C$ 430

One-way from

C$ 256

Popular in

January

Cheapest in

February

Average price

C$ 651

Good round-trip deal

C$ 587 or less

Good one-way deal

C$ 314 or less
Air Canada
  • Air Canada
  • 23/5-24/5
  • 2 total stops
  • 11h 45m total
  • Ottawa to Illinois
Search Deals
Air Canada
  • Air Canada
  • 7/6
  • 1 total stop
  • 6h 06m total
  • Ottawa to Illinois
Search Deals
Highest demand for flights based on searches. 13% potential increase in price (C$ 127 potential increase over avg. RT price).
Search Deals
Cheapest flight prices on average. 7% potential price decrease (C$ 60 potential savings vs. average RT price).
Search Deals
Average for round-trip flights in April 2026
Search Deals
Price to beat on a round-trip flight from Ottawa to Illinois.
Search Deals
Price to beat on a one-way flight from Ottawa to Illinois.
Search Deals

Cheapflights Fare Finder

 
Customize your flight search to find flights from Ottawa to Illinois 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 629,999 searches. Data last updated 30 April 2026.
Use the filters below to find and compare flights from Ottawa to Illinois that are best for you.

Fly from

Fly to

Route

Depart

Return

Price

Cheapest round-trip

OttawaSt. Louis

YOW - STL

YOWSTL

Ottawa

Sat 23/5

10:44 a.m.-3:46 p.m.

1 stop6h 02m

Lambert-St Louis

Wed 27/5

6:00 a.m.-10:05 p.m.

1 stop15h 05m

C$ 438

OttawaSt. Louis

YOW - STL

YOWSTL

Ottawa

Fri 24/7

6:25 a.m.-3:46 p.m.

1 stop10h 21m

Lambert-St Louis

Sat 8/8

1:13 p.m.-9:35 p.m.

1 stop7h 22m

C$ 438

OttawaSt. Louis

YOW - STL

YOWSTL

Ottawa

Tue 2/6

6:00 a.m.-3:46 p.m.

2 stops10h 46m

Lambert-St Louis

Wed 3/6

6:00 a.m.-10:05 p.m.

1 stop15h 05m

C$ 438

OttawaChicago

YOW - MDW

YOWMDW

Ottawa

Sun 14/6

11:00 a.m.-2:35 p.m.

1 stop4h 35m

Chicago Midway

Sun 21/6

3:20 p.m.-8:04 p.m.

1 stop3h 44m

C$ 520

OttawaChicago

YOW - MDW

YOWMDW

Ottawa

Fri 24/7

11:00 a.m.-2:35 p.m.

1 stop4h 35m

Chicago Midway

Sun 26/7

3:20 p.m.-9:44 p.m.

1 stop5h 24m

C$ 614

OttawaChicago

YOW - MDW

YOWMDW

Ottawa

Fri 5/6

2:20 p.m.-11:04 a.m.

2 stops21h 44m

Chicago Midway

Sun 7/6

10:15 a.m.-5:54 p.m.

1 stop6h 39m

C$ 669

OttawaChicago

YOW - MDW

YOWMDW

Ottawa

Fri 26/6

11:00 a.m.-2:35 p.m.

1 stop4h 35m

Chicago Midway

Fri 28/8

3:20 p.m.-8:04 p.m.

1 stop3h 44m

C$ 713

OttawaChicago

YOW - MDW

YOWMDW

Ottawa

Sat 6/6

9:35 a.m.-9:35 a.m.

1 stop25h 00m

Chicago Midway

Sun 7/6

3:20 p.m.-8:04 p.m.

1 stop3h 44m

C$ 714

OttawaChicago

YOW - MDW

YOWMDW

Ottawa

Mon 15/6

8:50 p.m.-9:40 a.m.

1 stop13h 50m

Chicago Midway

Sat 27/6

10:25 a.m.-7:09 p.m.

1 stop7h 44m

C$ 714

OttawaChicago

YOW - MDW

YOWMDW

Ottawa

Fri 19/6

11:00 a.m.-2:35 p.m.

1 stop4h 35m

Chicago Midway

Sat 27/6

10:25 a.m.-7:09 p.m.

1 stop7h 44m

C$ 748

Flights are sorted by cheapest round-trip flights first.

Deals found on 25/4

Showing 1-10 of 45 resultsSorted by cheapest first
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2
3
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5

Best time to book a flight from Ottawa to Illinois

Have a flexible travel schedule? Discover the best time to fly to Illinois from Ottawa 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.

Cheapflights Insights

Everything you need to know about your flight from Ottawa to Illinois

How far ahead should I book a flight from Ottawa to Illinois?

Booking 29 days in advance of your planned departure date is, on average, the best time to get cheap flights from Ottawa to Illinois. The general trend is that the closer you book to the departure date, the more expensive your flight will be.

What is the cheapest month to book a flight from Ottawa to Illinois?

Currently, August is the cheapest month in which you can book a flight from Ottawa to Illinois (average of C$ 179). Flying from Ottawa to Illinois in January is currently the most expensive (average of C$ 737). 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.

What is the cheapest time of day to fly from YOW to IL?

Find hourly flight availability from Ottawa to Illinois. Discover flight options and departure times throughout the day, allowing you to choose a departure time that suits your schedule. Data last updated 30 April 2026.

When flying from Ottawa to Illinois, the time of day you decide to fly out makes little to no difference towards the overall price you’ll pay on tickets.

Weekly flight availability from Ottawa to Illinois

Explore weekly flight availability from Ottawa to Illinois. Discover flights operating on different days of the week, giving you the flexibility to choose a travel day that best fits your plans. Compare info to find the most convenient option for your journey. Data last updated 30 April 2026.

The most flights from YOW to USIL are scheduled on a Monday (13 on average). You will have fewer flight options on Thursday, which is when the least amount of flights are scheduled (11 on average).

How much does it cost to fly round-trip from Ottawa to Illinois?

Reviews of airlines servicing Illinois

Get insights into the airlines that provide service to Illinois. 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 Illinois. Reviews last updated 30 April 2026.
Read reviews from past customers who have flown Porter Airlines,United Airlines, andAir Canada from Ottawa to Illinois. Reviews also offer insight into each airline's entertainment options, comfort, food, crew/service, and boarding process.
Porter Airlines
8.0
Very good
435 reviews
Check prices

Comfort

8.0

Boarding

8.2

Entertainment

7.0

Overall

8.0

Food

7.6

Crew

8.6

Reviews

1 / 20
10.0
Excellent

John,Mar 2026

YYZ - PVR

I'm 6ft 4in. The seats don't have enough room. But was a good flight.
Porter Airlines
8.0
Very good
435 reviews
Porter Airlines
8.0
Very good
435 reviews
Check prices

Comfort

8.0

Boarding

8.2

Entertainment

7.0

Overall

8.0

Food

7.6

Crew

8.6

Reviews

1 / 20
10.0
Excellent

John,Mar 2026

YYZ - PVR

I'm 6ft 4in. The seats don't have enough room. But was a good flight.
United Airlines
7.4
Good
9,677 reviews
Porter Airlines
8.0
Very good
435 reviews
Check prices

Comfort

8.0

Boarding

8.2

Entertainment

7.0

Overall

8.0

Food

7.6

Crew

8.6

Reviews

1 / 20
10.0
Excellent

John,Mar 2026

YYZ - PVR

I'm 6ft 4in. The seats don't have enough room. But was a good flight.
Air Canada
7.1
Good
10,982 reviews
Porter Airlines
8.0
Very good
435 reviews
Check prices

Comfort

8.0

Boarding

8.2

Entertainment

7.0

Overall

8.0

Food

7.6

Crew

8.6

Reviews

1 / 20
10.0
Excellent

John,Mar 2026

YYZ - PVR

I'm 6ft 4in. The seats don't have enough room. But was a good flight.

Related info for your journey

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

  • What airport do you fly from for flights from Ottawa to Illinois?

    Ottawa (YOW) is the airport you will fly out of if you book a flight from Ottawa to Illinois. It is only a 10.6 km journey to Ottawa (YOW) from Ottawa’s city centre.

  • How long is the flight from Ottawa to Illinois?

    United Airlines, Porter Airlines, and Air Canada can get you from Ottawa to Illinois in just under 4h 15m. Your travel time can differ by up to 3h 20m. There are 1051 km between Ottawa and Illinois. When browsing for deals, the options you’ll see will be for both direct flights and flights with stops.

  • What are the most popular routes from Ottawa to Illinois?

    Most travellers choose Ottawa - Chicago O'Hare Intl, Ottawa - Chicago Midway or Ottawa - Lambert-St Louis when deciding on the best route from Ottawa to Illinois.

  • What are the most reliable airlines from Ottawa to Illinois?

    Before booking your flight to Illinois from Ottawa, check out the most reliable airlines to get you to your destination on time: Republic Airways (72%), ANA (70%), Air Canada( 66%).

  • What are the cheapest flights from Ottawa to Illinois?

    Looking for the cheapest flight from Ottawa to Illinois? While on average our users pay C$ 678, our data indicates the cheapest price to be C$ 261. The most popular route (Ottawa - Chicago O'Hare Intl), is priced around C$ 575.

  • Can I find deals for flights from Ottawa to Illinois that include hotel bookings?

    Yes. In addition to deals on Ottawa to Illinois flights, Cheapflights offers vacation packages that include both flights and hotel.

  • How can I find direct flights from Ottawa to Illinois?

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

  • Can I find deals for business class flights from Ottawa to Illinois?

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

  • What is the cheapest month to book a flight from Ottawa to Illinois?

    Currently, August is the cheapest month in which you can book a flight from Ottawa to Illinois (average of C$ 179). Flying from Ottawa to Illinois in January is currently the most expensive (average of C$ 737). 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 Ottawa to Illinois

See prices for flight routes from nearby airports that may be better suited for you.
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Top 3 airlines flying from Ottawa to Illinois

Discover the top 3 airlines that operate flights from Ottawa to Illinois. 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 629,999 searches. Data last updated 30 April 2026.
AirlineCheapestAverageFlexibilityOn-time
Porter AirlinesCheapestC$ 317AverageC$ 436FlexibilityNo cancel feeOn-time52%
Search Porter Airlines flights
Air CanadaCheapestC$ 419AverageC$ 548FlexibilityNo cancel feeOn-time67%
Search Air Canada flights
United AirlinesCheapestC$ 459AverageC$ 563FlexibilityNo cancel feeOn-time69%
Search United Airlines flights

Fly with Cheapflights

Find the best flight deals on Cheapflights, where travelers can enjoy low prices and a wide availability of flights to their desired destinations.

How does Cheapflights help users find flights from Ottawa to Illinois?

Cheapflights makes it easy to find Ottawa to Illinois 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.

Why should you use Cheapflights to find cheap flight tickets from Ottawa to Illinois?

Cheapflights helps you find that perfect flight to Illinois from Ottawa by searching from hundreds of airlines and agencies you know and love. We are also free to use, in case you were wondering!

Can Cheapflights find flights from Ottawa to Illinois with no change fees?

Yes! Cheapflights helps users easily find flights from Ottawa to Illinois with no change fees.

Can Cheapflights notify me if prices for flights from Ottawa to Illinois become cheaper?

Yes, and it’s super simple to set up. Click the bell icon next to the flight deals above and provide a valid email address to enable Price Alerts. That’s it!

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