Cheap flights from Portland, Maine to Chicago from $97

The month of September is, on average, the cheapest month to fly to Chicago from Portland, Maine, with most prices found around $281. If you’re not able to fly to Chicago in September, then May is your next best option. Flight prices from Portland, Maine to Chicago during May average around $293.

The cheapest day to depart on your flight to Chicago is on a Thursday when prices can be found for as low as $424. This is often the case because there is less demand to fly during this day of the week. When flying out on a Sunday, the most expensive travel day of the week, you can expect to see flight prices from Portland, Maine to Chicago for around $575.

Our most recent data shows that the best time of day to fly to Chicago is in the afternoon. Flights from Portland, Maine to Chicago during this time can be as low as $414. In contrast, the most expensive time of day to depart to Chicago is in the morning when prices are around $470.

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

You are more likely to see cheaper flights to Chicago from Portland, Maine when booking weeks ahead of your departure date. In general, you can expect to find flights to Chicago for around $340 when searching weeks out. However, flight prices might be lower outside of this timeframe. For example, people recently found flights to Chicago from Portland, Maine for as low as $233 on momondo.

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

You could potentially save up to 1% on your flight if you consider stops on a Portland, Maine to Chicago flight.

As of March 2026, prices for Portland, Maine to Chicago flights are approximately 31% more expensive when compared to flights at the same time last year.

Delta, United Airlines, and American Airlines are the most popular carriers operating from Portland to Chicago

American Airlines, United Airlines and Delta are the top three most popular airlines that fly to Chicago from Portland, Maine according to our data. American Airlines is the first choice among our users, with 41% of people opting to fly with this airline when traveling to Chicago. Keep in mind that there are 6 different airlines that fly to Chicago on a routine basis, so you have a few additional options to choose from.

Chicago (ORD) was the most common stop: 50% of momondo users choosing 1-stop flights on this route connected there.

Flights via Chicago (ORD) offer the lowest average round-trip price of $253.

Flights connecting via Philadelphia (PHL) have the shortest average one-way travel time: 5h 02m.

Philadelphia (PHL) has the shortest average layover time for this route: 0h 53m.

5 flights are operational daily from Portland, Maine to Chicago as of March 2026. The most popular departure time for this route is 5:00PM, with 68% of flights per day taking off in the afternoon.

As of March 2026, 36 flights take off from Portland, Maine and land in Chicago each week. The most common flight departure day for this route is Mon, with 22% of weekly flights taking off on this day.