Cheap Flights from Shannon to Chicago

June comes out cheapest in the fare calendar, so early summer is the window to target when your dates can move. The priced months stretch from September through June, which gives autumn and spring a full spread of dated fares, with the Christmas weeks in December, Thanksgiving in November and the St Patrick's Day travel in March as the busy patches inside that range. Midweek departures usually sit below weekend ones, so shifting a flight by a day or two can change what you pay.

There is no budget side to this market: both Aer Lingus and United Airlines are full-service carriers, and with no nonstop flights between Shannon and Chicago, each one sells the trip with a connection. Cabin baggage and onboard service come as standard with either, while checked bags, seat selection and change conditions depend on the fare tier, so read what each fare includes before paying. Because a connection sits inside every itinerary, judge the two carriers on total journey time and where they land you, not on the fare alone.

O'Hare International is a large, busy hub, so expect long corridors, shuttle trains between terminals and a real queue at passport control on arrival; Midway International is smaller and quicker to walk out of. O'Hare sits on the city's northwest side and Midway on the southwest, and the L runs into the Loop from both — the Blue Line from O'Hare, the Orange Line from Midway — with taxis and rideshares as the other option. US entry formalities happen at your first American airport either way, so leave buffer time after landing.

Currency

USD ($)

Power sockets

Type A, B · 120 V

Language

Samoan, Hawaiian, Chamorro, Carolinian, Spanish

Emergency number

911

Driving side

right

Calling code

+1

Internet domain

.us

Population of Chicago

2.7 M (2020)

Time zone

UTC-05 (America/Chicago)

Country facts: Wikidata

• Sort out your US entry paperwork first, because most visitors from Ireland need an approved ESTA before boarding.
• Make sure your passport stays valid for your whole stay in the United States.
• Compare itineraries by arrival airport, since O'Hare and Midway put you on opposite sides of Chicago.
• Look closely at the connection in every itinerary, because a long layover can outweigh a small fare saving.
• Confirm what your fare tier includes, as checked baggage and seat selection differ between Aer Lingus and United fares.
• Aim for June when you want the lower end of the calendar, and book December dates early.