£401 Cheap flights to Illinois

The majority of momondo users who fly to Illinois tend to spend time in Chicago, which is visited 99% more often than other cities. When flying to Chicago, the most popular airport to fly into is Chicago O'Hare Intl Airport.

Grant Park is closest to Chicago O'Hare Intl Airport. Those looking for an alternative airport option near Grant Park could try flying into Chicago Midway Airport.

The most often visited landmarks in Illinois are Grant Park, Magnificent Mile, and Oak Street Beach, among many others that can be found in the area.

Illinois typically has a temperature range from -5 °C(January) to 23 °C(July). Those looking to avoid rain and/or snow while visiting Illinois should plan their trip in January, February, or December, as these months are relatively less likely to have precipitation.

You can find flights to Illinois from 16 airlines. If you’re unsure which to fly with, consider booking your flight with British Airways, Aer Lingus or Icelandair as these are the most popular among our users. British Airways is the most favoured with 54% of momondo travellers booking flights with this airline.

You can expect to spend an average of £1,222 for a flight to Illinois. However, our users found flights to Illinois for £368, which is the cheapest price we’ve seen in the past week. £2,287 per ticket tends to be the most expensive a flight to Illinois will get, whereas anything for £1,086 or less is considered a good deal.

The best day to take a flight to Illinois is on Wednesday, followed by Thursday. Wednesday and Thursday tend to have the lowest flight prices to Illinois. If your travel dates are flexible, then try to avoid booking on a Sunday, which is known for being the most expensive day of the week to fly to Illinois.

Prices for flights to Illinois were last updated today.

As of February 2026, there are 27 operators available to choose from for flights to Illinois.

The minimum age a child must be to fly alone is five but airlines that offer an unaccompanied minor (UNMR) service will have their own age restrictions, including rules around flight length, timings, and stopovers. We always recommend checking with the individual airline you are booking with to travel to Illinois.

The travel and health documents you'll need for your trip to Illinois may differ based on your itinerary and personal situation. Typically, you should have several documents on hand, such as a national ID card or driver's license and a passport that is valid for six months after your intended arrival at Illinois. It is always advisable to seek advice from your airline or a trusted third party, such as IATA.