Cheap flights from Portland, Maine to Illinois from $180

The cheapest month to fly to Illinois from Portland, Maine is in January. Flight prices, which tend to average around $329, are often lower during this time because this is during the off-season. If you aren’t able to travel to Illinois during the month of January, then flying in May is also cheap. Prices for this month can be found on momondo for an average of $332.

The cheapest day to depart from Portland, Maine to Illinois is on a Wednesday when prices can be found for as low as $463. Flights from Portland, Maine to Illinois on a Sunday will generally be more expensive and average around $628. Keep in mind that these prices on both days could fluctuate depending on the season and the demand.

Our most recent data shows that the best time of day to fly to Illinois is in the evening. Flights from Portland, Maine to Illinois during this time can be as low as $412. Flights in the morning are often more expensive with an average ticket price of $512.

Fly from Portland to Chicago O'Hare Intl for the best Portland - Illinois flight prices

You are more likely to see cheaper flights to Illinois from Portland, Maine when booking weeks ahead of your departure date. In general, you can expect to find flights to Illinois for around $391 when searching weeks out. However, flight prices might be lower outside of this timeframe. For example, people recently found flights to Illinois from Portland, Maine for as low as $304 on momondo.

There are 4 cabin classes available to choose from on Portland, Maine to Illinois flights. Cabin price and availability will vary by airline so perform a search above to find the right deals for you.

Delta, Southwest, and United Airlines are the most popular carriers operating from Portland to Illinois

American Airlines, United Airlines and Delta are the top three most popular airlines that fly to Illinois from Portland, Maine according to our data. American Airlines is the first choice among our users, with 40% of people opting to fly with this airline when traveling to Illinois. Keep in mind that there are 5 different airlines that fly to Illinois on a routine basis, so you have a few additional options to choose from.

As of November 2026, there are 3 flights per day flying from Portland, Maine to Illinois. The most common time of day flights depart is 12:00PM, with 72% of flights taking off in the afternoon.

21 flights are operational weekly from Portland, Maine to Illinois as of November 2026. The most popular departure day for this route is Thu, with 33% of flights per week taking off on this day.