Cheap flights from Chicago O'Hare Intl Airport to Portugal from $277

The cheapest month to fly to Portugal from Chicago O'Hare Intl Airport is in February. Flight prices, which tend to average around $618, are often lower during this time because this is during the off-season. If you aren’t able to travel during the month of February, then book flights to Portugal from Chicago O'Hare Intl Airport during January instead. Flights to Portugal in January, while not as cheap as those in February, still average around $621.

According to our data, Wednesday is the cheapest day to fly to Portugal from Chicago O'Hare Intl Airport. The lowest ticket price found for a Wednesday departure recently was $689. 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 Saturday, with ticket prices averaging around $858.

Our most recent data shows that the best time of day to fly to Portugal is in the evening. Flights from Chicago O'Hare Intl Airport to Portugal during this time can be as low as $654. In the afternoon is when there is more demand to fly to Portugal, so prices are often more expensive at around $830 per ticket.

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

You are more likely to see cheaper flights to Portugal from Chicago O'Hare Intl Airport when booking weeks ahead of your departure date. In general, you can expect to find flights to Portugal for around $860 when searching weeks out. However, flight prices might be lower outside of this timeframe. For example, people recently found flights to Portugal from Chicago O'Hare Intl Airport for as low as $783 on momondo.

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

SWISS, Delta, and Lufthansa are the most popular carriers operating from Chicago O'Hare Intl to Portugal

TAP AIR PORTUGAL, United Airlines and Aer Lingus are the top three most popular airlines that fly to Portugal from Chicago O'Hare Intl Airport according to our data. TAP AIR PORTUGAL is the first choice among our users, with 69% 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 28% 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 132 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.

Thursday 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 28% of their flights experiencing any sort of delay.

As of September 2026, there are 1 flights per day flying from Chicago O'Hare Intl Airport to Portugal. The most common time of day flights depart is 6:00PM, with 100% of flights taking off in the evening.

As of September 2026, there are 10 flights per week flying from Chicago O'Hare Intl Airport to Portugal. The most common day of the week flights depart is Wed, with 20% of flights taking off on this day.