$175 Find Cheap Flights from Ottawa to Illinois

This is the cheapest one-way flight price found by a KAYAK user in the last 72 hours by searching for a flight from Ottawa to Illinois departing on 5/29. 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.
1 adult
1 adult, Economy, 0 bags

KAYAK searches hundreds of travel sites at once for deals on flights to Illinois

 
These are the airlines KAYAK users have selected most often from within our search results in flight searches from Ottawa to Illinois, as well as popular online travel agencies
These are the airlines KAYAK users have selected most often from within our search results in flight searches from Ottawa to Illinois, as well as popular online travel agencies
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Cheap Flights from Ottawa to Illinois

Cheapest round-trip prices found by our users on KAYAK in the last 72 hours
Chicago
Chicago1 stop$335
Bloomington
Bloomington1 stop$430
St. Louis
St. Louis1 stop$320
Chicago
Chicago1 stop$335
Bloomington
Bloomington1 stop$430
St. Louis
St. Louis1 stop$320

Book Cheap Ottawa to Illinois Plane Tickets

 
Here are some of the best deals found on KAYAK recently from the most popular airlines for round-trip flights from Ottawa to Illinois that are departing in the next months. While these flights were available on KAYAK in the last 72 hours, prices and availability are subject to change and deals may expire.
Discover the best prices for you by selecting your travel dates on KAYAK.

Recent round-trip flight deals from Ottawa to Illinois

Sun, May 10 - Sun, May 17
Air Canada Logo
7:00 am - 12:06 pm
YOW
-
STL
6h 06m
1 stop
Air Canada Logo
7:05 am - 1:05 pm
STL
-
YOW
5h 00m
1 stop
$320Air Canada
Sat, May 30 - Sat, Jun 6
Multiple Airlines Logo
7:00 am - 11:13 pm
YOW
-
ORD
17h 13m
1 stop
Multiple Airlines Logo
8:05 am - 12:20 am
ORD
-
YOW
15h 15m
2 stops
$335Multiple Airlines
Fri, Jun 19 - Mon, Jun 22
Air Canada Logo
7:00 am - 12:21 pm
YOW
-
STL
6h 21m
1 stop
Air Canada Logo
2:15 pm - 9:15 pm
STL
-
YOW
6h 00m
1 stop
$336Air Canada
Tue, Jul 14 - Sat, Jul 18
United Airlines Logo
5:50 pm - 11:36 pm
YOW
-
STL
6h 46m
1 stop
United Airlines Logo
6:00 am - 5:07 pm
STL
-
YOW
10h 07m
1 stop
$337United Airlines
Tue, Jul 14 - Sat, Jul 18
United Airlines Logo
6:25 am - 3:46 pm
YOW
-
STL
10h 21m
1 stop
United Airlines Logo
6:00 am - 9:35 pm
STL
-
YOW
14h 35m
1 stop
$339United Airlines
Fri, Jun 5 - Mon, Jun 8
Air Canada Logo
7:00 am - 12:06 pm
YOW
-
STL
6h 06m
1 stop
Air Canada Logo
2:15 pm - 9:16 pm
STL
-
YOW
6h 01m
1 stop
$348Air Canada
Thu, May 28 - Thu, Jun 4
Porter Airlines Logo
8:00 am - 2:35 pm
YOW
-
MDW
7h 35m
1 stop
Porter Airlines Logo
10:25 am - 5:54 pm
MDW
-
YOW
6h 29m
1 stop
$419Porter Airlines
Tue, May 5 - Fri, May 29
Porter Airlines Logo
11:00 am - 2:35 pm
YOW
-
MDW
4h 35m
1 stop
Porter Airlines Logo
3:20 pm - 8:04 pm
MDW
-
YOW
3h 44m
1 stop
$429Porter Airlines
Sat, May 9 - Tue, May 12
Delta Logo
6:55 am - 3:29 pm
YOW
-
BMI
9h 34m
2 stops
Delta Logo
6:00 am - 5:35 pm
BMI
-
YOW
10h 35m
2 stops
$581Delta
Sat, May 9 - Tue, May 12
Delta Logo
6:55 am - 3:29 pm
YOW
-
BMI
9h 34m
2 stops
Delta Logo
6:00 am - 5:35 pm
BMI
-
YOW
10h 35m
2 stops
$608Delta
Booking Insights

KAYAK's insights & trends for Ottawa to Illinois flights

Get data-powered insights and trends into flights from Ottawa to Illinois to help you find the cheapest flights, the best time to fly and much more.

How much is a round-trip flight from Ottawa to Illinois?

This analysis is based on the cheapest round-trip price found on KAYAK in the last 12 months by searching for a flight from Ottawa to Illinois departing in May.

What is the cheapest Ottawa to Illinois flight route?

Data is based on round-trip flight searches on KAYAK over the past month.

The cheapest ticket to Illinois from Ottawa found in the last 72 hours was to Chicago, at $286 round-trip. The most popular route is from Ottawa (YOW) to Chicago O'Hare Intl Airport (ORD), and the cheapest round-trip airline ticket found on this route in the last 72 hours was $286.

What is the cheapest time of day to fly to Illinois?

The average price for all round-trip flights from Ottawa to Illinois depending on the time of departure, clicked by users on KAYAK in the last 2 weeks.

The cheapest time of day to fly to Illinois is generally in the evening, when round-trip flights cost $521 on average. Morning departures are around 21% more expensive than evening flights, on average. The most expensive time of day to fly to Illinois is generally in the morning, which is peak travel time and where the average cost of a ticket is $629.

Can I save money by flying with a layover from Ottawa to Illinois?

The average round-trip price for all non-stop flights, flights with one layover, and flights with two layovers for the route found by users searching on KAYAK in the last 2 weeks.

Yes, flying with a layover may cost you more time, but you can also save money on the route, with a 1 stop layover the cheapest option at $441 on average.

What is the cheapest month to fly from Ottawa to Illinois?

To calculate monthly average prices, KAYAK takes all prices for each month over the last year for round-trip flights from Ottawa to Illinois, removes the top 0.1% to account for outliers, and then takes the median of all values for each month.

The cheapest month for flights from Ottawa to Illinois is February, when tickets cost $253 (return) on average. On the other hand, the most expensive months are January and November, when the average cost of round-trip tickets is $795 and $549 respectively.

What’s the cheapest day of the week to fly from Ottawa to Illinois?

The average price of all round-trip flights from Ottawa to Illinois clicked on KAYAK for each day over the last 12 months.

For Ottawa to Illinois, Saturday is the cheapest day to fly on average and Monday is the most expensive. Flying from Illinois back to Ottawa, the best deals are generally found on Saturday, with Tuesday being the most expensive.

Good to know

Low seasonJanuary
Cheapest flight$175
Best time to beat the crowds but there is an average 27% increase in price.
Most popular time to fly with an average 9% increase in price.
Flight from Ottawa to Chicago O'Hare Airport

FAQs - booking Illinois flights

  • How does KAYAK find such low prices on flights from Ottawa to Illinois?

    KAYAK is a travel search engine. That means we look across the web to find the best prices we can find for our users. With over 2 billion flight queries processed yearly, we are able to display a variety of prices and options on flights from Ottawa to Illinois.

  • How does KAYAK's flight Price Forecast tool help me choose the right time to buy my flight ticket from Ottawa to Illinois?

    KAYAK’s flight Price Forecast tool uses historical data to determine whether the price for a flight from Ottawa to Illinois is likely to change within 7 days, so travelers know whether to wait or book now.

  • What is the Hacker Fare option on flights from Ottawa to Illinois?

    Hacker Fares allow you to combine one-way tickets in order to save you money over a traditional round-trip ticket. You could then fly from Ottawa to Illinois with an airline and back with another airline.

  • What is KAYAK's "flexible dates" feature and why should I care when looking for a flight from Ottawa to Illinois?

    Sometimes travel dates aren't set in stone. If your preferred travel dates have some wiggle room, flexible dates will show you all the options when flying from Ottawa to Illinois up to 3 days before/after your preferred dates. You can then pick the flights that suit you best.

Top tips for finding cheap flights to Illinois

  • Looking for a cheap flight? 25% of our users found tickets from Ottawa to the following destinations at these prices or less: Chicago $215 one-way - $416 round-trip

Reviews of the top airlines flying from Ottawa to Illinois

 
See real verified KAYAK customer reviews for airlines flying from Ottawa to Illinois. Airline scores are aggregated from all reviews left by passengers on KAYAK after flying with an airline. KAYAK doesn’t show reviews that are older than 5 years. Learn how KAYAK collects reviews.
Need help choosing which airline to fly with from Ottawa to Illinois? KAYAK airline reviews give an overall score for each airline based on loads of factors, including comfort, boarding, in-flight entertainment and more, to make your decision easier. See airline scores according to verified KAYAK customer reviews.
8.0
Porter AirlinesOverall score based on 435 reviews
8.2Boarding
7.0Entertainment
8.0Comfort
7.6Food
8.6Crew
Airline reviews

I didn’t receive any help when they messed up and wasn’t honest and the supervisor did absolutely nothing to help me so I had to buy another ticket at $537

10.0 ExcellentAnonymous, Apr 2026
YHM - YHZ
Read more Porter Airlines reviews

I didn’t receive any help when they messed up and wasn’t honest and the supervisor did absolutely nothing to help me so I had to buy another ticket at $537

Even tho the flight was a bit delayed the team was apologetic. Everyone was friendly and efficient.

The Flight took off 2hrs late because there was no pilot showing up when the flight was ready to board.. Though the cabin crew was present and had prepared the plane, the FO turned around after 15 min and went away. A crew to fly the plane finally arrived over an hour later and we were able to board 1h30 min later than planned time... until everything was loaded, we left 2h late from the gate. This was a small plane, so don't expect any Entertainment... Wi-Fi access on board would work, but took an awful amount of time to figure out and get it work (I'm an IT person). Flying as VIPorter customer, I was expecting at least some warm meal, but everything served was just cold.. except the coffee maybe. Even in so-called VIPorter seats, space is cramped and trays are so tiny, you can barely setup your food. Flight caught up during the coast-to-coast crossing and was able to recoup about 45 min from the delay.. still arrived very late in Vancouver and had to wait a long time to get our registered bags. Let's see how the return flight will be in a few days..

It was okay. Had a thing with the front desk, she had me repack my suitcases to have them be under the weight restrictions, but then the other one was overweight, she argued with me about it when there were tons of people in line. Wasn’t great.

Due to a known technical error that Porter has not fixed in over a year, I was unable to check in the children on my reservation online and had to do it at the airport. Upon check in, there were no seats together, which was an issue as we had young children. The gate agent did manage to seat us together by moving other passengers, which was appreciated, but the other passengers were never informed, leading to confusion and delay upon boarding. The flight was over an hour late; no explanation or apology was ever issued. The bags on Porter take a long time to arrive--over half an hour at Hamilton on my inbound flight, and not much better on my return to Edmonton.

On my e-boarding pass it shows free wifi, yet the plane I was on didn’t have wifi. Please remove false advertising from your website and boarding passes

3.5 hr delay for a 1 hr work flight. No information as to why the delay until 20 mins before boarding.

Organization and the adjusted times but the snacks could be of a bigger portion

Smaller plane. Food and bar service for free is amazing. Drinks were in glass not plastic cups.

Poor landing as we overshot the runway and had to re land the plane. Lost both of my luggage not found as of yet. Had to pay extra money for my luggage in USD, now great my luggage is gone. Will not fly with Porter again.

Very comfortable flight, snacks and drinks were good, good communication from crew. Could have used a little more information on timing of boarding for group 5

Great flight. Got to watch a movie. Smooth flight and early arrival at ORD.

It was better than excellent. The staff in Mason City were great. The young woman that pushed my wheelchair did more than could be expected of her. She came from India 17 years ago. I don't remember her name.

After arriving in Chicago, we were taxiing for 1.5 hours with infrequent and untruthful updates about the amount of time it would take to arrive at the gate. Minimally, the team could have provided timing expectations that were more truthful, especially one their original expectations were not met.

The crew was generally professional. Though one of the crew members seemed to be easily annoyed, the others were fine and helpful. The green olives and almonds snack was really good. A great idea, and nice balance of tastes.

Every staff member was professional, friendly and courteous. The pizza twist was ok. It was warm but too much dough.

I had a terrible experience. My flight got delayed from Atlanta to Chicago on Monday April 6, 2026, and that led to me missing my next flight to Brussels. United Airlines didn’t provide me with any accommodation for shelter. I had to sleep at the airport in Chicago. The next flight I was put on didn’t leave until the evening hours of Tuesday 4/7/2026.

Food and drink service was very low quality. The flight attendants in business class must have been short some staff. Service was sluggish and not much English was spoken

The flight was officially delayed 3 times, and was actually later than that. Combined, it was a 3 hour delay, but there was no recognition (miles, voucher, etc). The crew seemed stressed. The captain sounded nervous in his announcements. The flight itself was smooth and uneventful.

Just a bad day to fly. Flight was delayed from scheduled 6:50 pm departure to 8:50 pm. Combination of factors mostly related to weather at the destination airport (which is where the incoming flight originated) which delayed the inbound flight over an hour. Once on board, we taxied but had to hold again on the taxiway for 10 minutes or so. We did not get wheels up until after 9 pm. The flight was smooth but about 18 minutes from our destination, we had to hold for several minutes more due to weather at ORD. We finally landed at ORD about 11:08 pm (accounting for the time difference, that was about a 3 hour delay from our scheduled departure time). It felt like we were never going to get to our destination. But the flight crew and attendants were very good. The movie selection onboard was also very nice. Got to watch half of a movie just during our taxi from the gate at ATL due to the delay!

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

Information on your arrival and departure airports