€313 Find Cheap Flights 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 Ireland to Illinois departing on 24/9. 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 for flights to Illinois
These are the airlines KAYAK users have selected most often from within our search results for flights to Illinois
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Flight Deals

Best Illinois Flight Deals

Cheapest return prices found by our users on KAYAK in the last 72 hours
Chicago
Chicago1 stop€534
St. Louis
St. Louis2 stops€760
Chicago
Chicago1 stop€534
St. Louis
St. Louis2 stops€760

Book Cheap Illinois Plane Tickets

 
Here are some of the best deals found on KAYAK recently from the most popular airlines for return flights 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 return flight deals to Illinois

Fri, 9 Oct - Mon, 12 Oct
Delta Logo
10:00 - 16:49
DUB
-
ORD
12h 49m
1 stop
Delta Logo
17:45 - 15:25
ORD
-
DUB
15h 40m
2 stops
€534Delta
Fri, 9 Oct - Mon, 12 Oct
Delta Logo
10:00 - 16:49
DUB
-
ORD
12h 49m
1 stop
Delta Logo
17:45 - 15:25
ORD
-
DUB
15h 40m
2 stops
€535Delta
Tue, 25 Aug - Sat, 29 Aug
Aer Lingus Logo
16:45 - 19:15
DUB
-
ORD
8h 30mdirect
Aer Lingus Logo
21:00 - 10:35
ORD
-
DUB
7h 35mdirect
€536Aer Lingus
Wed, 7 Oct - Mon, 12 Oct
Delta Logo
11:00 - 21:45
DUB
-
ORD
16h 45m
1 stop
Delta Logo
15:50 - 07:55
ORD
-
DUB
10h 05m
1 stop
€536Delta
Tue, 25 Aug - Sat, 29 Aug
Aer Lingus Logo
16:45 - 19:15
DUB
-
ORD
8h 30mdirect
Aer Lingus Logo
15:45 - 05:10
ORD
-
DUB
7h 25mdirect
€542Aer Lingus
Sat, 12 Sep - Sun, 20 Sep
United Airlines Logo
12:30 - 00:28
SNN
-
ORD
17h 58m
1 stop
United Airlines Logo
14:32 - 10:15
ORD
-
SNN
13h 43m
1 stop
€550United Airlines
Sat, 12 Sep - Sun, 20 Sep
United Airlines Logo
09:30 - 11:50
SNN
-
ORD
8h 20mdirect
United Airlines Logo
18:05 - 07:30
ORD
-
SNN
7h 25mdirect
€644United Airlines
Wed, 2 Sep - Sun, 6 Sep
American Airlines Logo
12:40 - 20:26
DUB
-
STL
13h 46m
1 stop
American Airlines Logo
12:41 - 09:35
STL
-
DUB
14h 54m
1 stop
€853American Airlines
Mon, 10 Aug - Tue, 25 Aug
Finnair Logo
09:30 - 00:14
DUB
-
STL
20h 44m
1 stop
Finnair Logo
16:54 - 11:50
STL
-
DUB
12h 56m
1 stop
€916Finnair
Thu, 16 Jul - Wed, 29 Jul
Finnair Logo
09:30 - 00:16
DUB
-
STL
20h 46m
1 stop
Finnair Logo
17:58 - 11:50
STL
-
DUB
11h 52m
1 stop
€920Finnair
Booking Insights

KAYAK's insights & trends for flights to Illinois

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

What is the cheapest flight to Illinois?

These are the best return prices found by users searching on KAYAK in the last 72 hours.

The cheapest ticket to Illinois from Ireland found in the last 72 hours was to Chicago O'Hare Intl Airport, at €549 return. The most popular route is Dublin (DUB) to Chicago O'Hare Intl Airport (ORD) and the cheapest return airline ticket found on this route in the last 72 hours was €549.

How much is a flight to Illinois?

The average and cheapest price for all round-trip flights to Illinois from each origin found by users searching on KAYAK in the last month.

A flight to Illinois costs €780 on average. The cheapest price found on KAYAK in the last 2 weeks was €493 for the route Dublin (DUB) to Chicago O'Hare Intl Airport (ORD). The most popular routes on KAYAK are Dublin to Chicago which costs €738 on average, and Shannon to Chicago, which costs €858 on average.

See prices from:

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

To calculate monthly average prices, KAYAK takes all prices for each month over the last year for flights from Ireland 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 Ireland to Illinois is June, when tickets cost €233 (return) on average. On the other hand, the most expensive months are September and August, when the average cost of round-trip tickets is €365 and €345 respectively.

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

The average price for all round-trip flights from Ireland 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 retur flights cost €617 on average. Morning departures are around 16% more expensive than evening flights, on average. The most expensive time of day to fly to Illinois is generally in the afternoon, which is peak travel time and where the average cost of a ticket is €806.

How far in advance should I book a flight from Ireland to Illinois?

To calculate weekly average prices, KAYAK takes all prices for each week before departure over the last year for round-trip flights to Illinois, removes the top 0.1% to account for outliers, and then takes the average of all the values for each week.

To get a below-average price on a flight from Ireland to Illinois, you should book around 3 weeks before departure, which saves you about 32% compared to booking last-minute. For the absolute cheapest price, our data suggests you should book 16 weeks before departure.

Which is the cheapest airport to fly into in Illinois?

Prices will differ depending on the departure airport, but generally, the cheapest airport to fly to in Illinois is Chicago O'Hare Intl Airport (ORD), with an average flight price of €805.

Good to know

Low seasonJanuary
Cheapest flight€313
Best time to beat the crowds (4% less expensive on average)
Most popular time to fly and prices are also 9% lower on average.
Flight from Cork to Chicago O'Hare Airport

FAQs - booking Illinois flights

  • How does KAYAK find such low prices on flights from Ireland 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 Ireland to Illinois.

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

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

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

    Hacker Fares allow you to combine one-way tickets in order to save you money over a traditional return ticket. You could then fly from Ireland 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 Ireland 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 Ireland to Illinois up to 3 days before/after your preferred dates. You can then pick the flights that suit you best.

  • What is the cheapest day to fly to Illinois?

    Based on KAYAK data, the cheapest day to fly to Illinois is Thursday when return tickets can be as cheap as €666. On the other hand, the most expensive day to fly is Sunday, when return prices are €794 on average.

Top tips for finding cheap flights to Illinois

  • Looking for cheap airfare to Illinois? 25% of our users found return tickets to Illinois for the following prices or less: From Shannon €798, from Dublin €1,171
  • Enter your preferred departure airport and travel dates into the search form above to unlock the latest Illinois flight deals.

Reviews of the top 5 airlines flying to Illinois

 
See real verified KAYAK customer reviews for airlines flying to Illinois. Airline scores are aggregated from all reviews left by passengers on KAYAK after flying with an airline from Ireland to Illinois. 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 Ireland 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.
7.6
FinnairOverall score based on 1415 reviews
7.7Boarding
8.2Crew
6.9Entertainment
7.4Comfort
6.7Food
Airline reviews

Late, dirty cabin, charging ports broken, uncomfortable, no tomato juice, barely edible food

4.0 OkayAnonymous, Jun 2026
HEL - LAX
Read more Finnair reviews

Late, dirty cabin, charging ports broken, uncomfortable, no tomato juice, barely edible food

Flight on time, landed well ahead of schedule. Attendants were excellent and responsive

The crew was friendly, and the flight landed on time

Rude Iberia security crew at the Madrid terminal. No Iberia officials to be found to redress complaints at the gate. No supervisors. Nothing for processing upgrades at the gate Iberia app did not work to let me upgrade my options to higher classes. No water was offered on a hot day in Madrid. Madrid airport air conditioning was so weak that people were sweating. Never book on any airlines that codeshare with Iberia.

Great if not for the boarding by bus at Heathrow terminal 3. Medieval disappointing time-consuming and very hard on handicapped flyers. It was awful

All reviews good because...flight from BWI to London ,economy seats was miserable. I usually book 1,step up from economy but this would have added 1500 bucks 1 way. Bit the bullet and upgraded for retun flight, otherwise all ratings would have been rock bottom.

It was okay. The airplane was a little smaller than a flight from Thailand to Helsinki.

Do not use KAYAK or Finair for future travel. Unless you purchase the tickets directly from the airline, you were going to have a difficult time checking in. Kayak canceled my flights twice and ended up causing great difficulty in me getting back from Europe because they double sold my tickets between American Airlines and Finair. The event caused significant delays and led to me having to rebook my flights.

It was listed on my ticket as Finnair but there was no indication that the flight was Finnair. In fact the number was even different. There were no employees there until exactly 2 hours before so we had to wait in line at Iberia and hope

Flight were delayed which made me miss all the other flights. Bags are still missing from 2 weeks ago. This airline is worse the Spirit Airlines!

1 flight cancelled Had to fly out of different city Flight at new departure city was delayed 3 hours causing us to miss connecting flights. By the time we did make it to Prague our luggage did not. Had to wait day and a half for luggage to be delivered. Customer service was not good. Agents did not arrive at gate until 5-10 minutes before boarding

Awful. Delayed flights, missed connection to Toronto. Hotel vouchers were for already booked hotels x3. Giant waste of my time

Boarding was great, and the crew were very friendly. The seats must have been a bit on the older side and you could feel some of the seat components through the padding. Also, the plugs did not work on the row's entertainment screen or charging ports. Checked bag was transferred for connecting flight, and we appreciated how early we had the connecting gate information.

Very easy ! Use the kiosk and bag drop and right to security within 10 min

Prefer not to have an almost 3 hour delay with useless communication that wasn't accurate.

Over 5 hour delay with minimal updates or ability to standby for alternative flights. During boarding and 1 hr+ wait for takeoff, seats were drenched w water from air conditioning condensation and always leftover crumbs on carpet and seats

I flew from Barcelona to Chicago on UA yesterday. The flight was on time, the pilots did a great job and the flight attendants were super nice. All of them. Also food was good, and the drinks, including wine were served a few times during our flight. I highly recommend this airline.

Boarded early, left early, arrived 40 mins early! A win win for me!

These airplanes should be illegal. The seats are two tight, it is a safety issue. Wheelchair support was ridiculously slow. We almost missed our flight.

This flight is a quick way to get to Chicago, but a bit expensive.

Everything was great!! I had no problems!! I would fly Aer Lingus again! 🥰

From Rome to Dublin if you want any refreshments you have to pay for them, Not used to this as we typically get soft drinks and a little snack on a 3hour flight in the US.

Small plane. Tight seating . What can one say except that it was fast!

The flights are literally always delayed arriving, boarding and taking off so they are always late for the connection. I planned ahead so I was okay but many others aren't. The food was terrible. The staff was very pleasant. I appreciate boarding back to front.

All aspects were excellent - it helped that the flight was only 2/3 full and I had no one sitting in my row. The Pre-check (US Passport Control and Customs) in Dublin made everything so easy when we arrived in Chicago.

Very nice experience. Flight had good entertainment system and good food options. Customer service was very friendly and nice as well.

The same as I stated prior. We incurred extra costs that should be reimbursed, given we were not communicated with about schedule changes.

My flight from Dublin was delayed two hours which ment that I missed my connecting flight to Phoenix. American Airlines provided a hotel room and rebooked my flight for 7:30 AM the next day. I didn't get to the room until 11 pm and I had to be at the airport the next day by 5 AM. The airlines did their best but the schedule was challenging for an 81 year old.

I like Aer Lingus so that is why I’m writing this critique so they can become better. The boarding gate was too small to board properly. Our seats were toward the back of the plane knowing we would be boarding after business class, we moved to that area after business class boarded. An Aer Lingus employee told us we couldn’t stand there. We explained we were the next group to board and wouldn’t even be able to hear when our boarding was called. She didn’t care and was not very professional. The cabin was freezing. I wouldn’t feed my dog the food. We were over an hour late coming into chicago because of weather which can’t be avoided. I asked the crew if they could make an annoucement for before whose final destination is chicago to wait and allow the people with connecting to deplane first. He said there are a lot of people with connecting flights. He said, it doesn’t matter. Well, yes it does. He could have been more considerate of his passengers.

Very pleasant staff, there was some turbulence but the captain was very apologetic and gave notice where possible.

Flight was delayed…once landed at ORD, no gates were available so made us wait for 56 minutes after we landed to let us out of the aircraft!

Very efficient boarding and quick flight. Attendants don’t come by often so would often have a lot of trash at seat.

The flight de-boarded after being informed of a 3 hour delay. The gate agent said we could go to lounge. The flight ended up boarding 20 minutes later and I missed it.

I love the e fact that the staff communicated swiftly when my flight was delayed and gate number changed

We had a mechanical delay which made us 90 minutes late (9:30 PM) then land and put into the penalty box because a plane was in our gate? What the hell! We should get priority.Damn American.

The seats were extremely cramped, with very little legroom or personal space. There was no room left in the overhead bins for a backpack, and the space under the seat in front was so limited that I could barely fit my bag underneath. Overall, the seating arrangement felt very uncomfortable and overcrowded.

weather delay of almost 2 hours then we landed and our gate wasn't available so we waited another 30 min

Delayed flight more than I hour. When boarding we spent some additional time on the plane before takeoff ....

The flight was delayed significantly and we sat on runway after landing for awhile. Best thing was the flight attendant, Jenny, in first class, who was very professional and attentive. She was excellent - the rest of the flight was not.

The flight was uneventful, which is always good. The plane was clean and seem to have a little bit more room. They fed us every couple hours, and we had a lot of in-flight entertainment. The staff was very helpful and attentive.

The legroom was lacking and the entertainment system lacked adequate selection of older films. Modern films are generally not very good.

Perfect airline, super friendly, great service, tasty food. Would fly again.

Everything could have been better. What needed to be wrong with United went wrong

It was good. The seats in economy weren’t bad

Very good. Comfortable and I felt well taken care of from start to finish

We were in premium economy seats that appeared to be locked in plae, No reclining. My aching back.

I don’t understand how they charge as much as they do for such a poor experience

I wish the plane had pod seating for business class. I had a window seat (8K) and I had to climb over the person sitting on the aisle when I needed to get up. Also there is no partition between the seats for privacy when sleeping. The Asian airlines have much nicer business class seating. Their seats are wider for better comfort when sleeping.

The seat space seemed small especially when the person ahead reclined but other than that, very good.

Luggage transfer in Chicago was not performed in time. I received my luggage at my destination two days later.

Everything you need to know for your flight to Illinois

Cabin class types available on flights to Illinois

Cabin classes available on flights to Illinois. Prices are the lowest found on KAYAK over the last 7 days. Price and availability is not guaranteed.