Cheap flights from Chicago to Portugal from $240

The cheapest month to fly to Portugal from Chicago is in August. Flight prices, which tend to average around $300, are often lower during this time because this is during the off-season. If you aren’t able to travel during the month of August, then book flights to Portugal from Chicago during February instead. Flights to Portugal in February, while not as cheap as those in August, still average around $360.

According to our data, Wednesday is the cheapest day to fly to Portugal from Chicago. The lowest ticket price found for a Wednesday departure recently was $625. Keep in mind that prices can always vary depending on your route and whether or not you are flying domestic or international. The most expensive day to fly to Portugal is Thursday, with ticket prices averaging around $829.

Our most recent data shows that the best time of day to fly to Portugal is in the evening. Flights from Chicago to Portugal during this time can be as low as $588. In the afternoon is when there is more demand to fly to Portugal, so prices are often more expensive at around $784 per ticket.

Fly from Chicago O'Hare Intl to Lisbon Humberto Delgado for the best Chicago - Portugal flight prices

You are more likely to see cheaper flights to Portugal from Chicago when booking weeks ahead of your departure date. In general, you can expect to find flights to Portugal for around $820 when searching weeks out. However, flight prices might be lower outside of this timeframe. For example, people recently found flights to Portugal from Chicago for as low as $717 on momondo.

There are 3 cabin classes available to choose from on Chicago to Portugal flights. Cabin price and availability will vary by airline so perform a search above to find the right deals for you.

United Airlines, KLM, and Delta are the most popular carriers operating from Chicago to Portugal

TAP AIR PORTUGAL, United Airlines and Aer Lingus are the top three most popular airlines that fly to Portugal from Chicago according to our data. TAP AIR PORTUGAL is the first choice among our users, with 68% of people opting to fly with this airline when traveling to Portugal. Keep in mind that there are 17 different airlines that fly to Portugal on a routine basis, so you have a few additional options to choose from.

Historically, on average around 36% of flights between Chicago and Portugal have experienced a delay on any given week. The average delay length over the past 12 months has been 131 minutes.

Generally, flights departing in the early afternoon tend to experience fewer delays. Flights in the evening have, in the past, seen delays more frequently in comparison.

Wednesday is statistically the day of the week which experiences the fewest number of delays on this flight route. Tuesday has historically seen more delays on average compared to the rest of the week.

According to our data, TAP AIR PORTUGAL have had the least number of delays on this route over the last 12 months; with about 35% of their flights experiencing any sort of delay.

1 flights are operational daily from Chicago to Portugal as of July 2026. The most popular departure time for this route is 6:00PM, with 100% of flights per day taking off in the evening.

As of July 2026, there are 7 flights per week flying from Chicago to Portugal. The most common day of the week flights depart is Fri, with 29% of flights taking off on this day.