Cheap flights from Washington, D.C. to Portugal from $340

The cheapest month to fly to Portugal from Washington, D.C. is in January. Flight prices, which tend to average around $201, are often lower during this time because this is during the off-season. If you aren’t able to travel during the month of January, then book flights to Portugal from Washington, D.C. during December instead. Flights to Portugal in December, while not as cheap as those in January, still average around $274.

According to our data, Monday is the cheapest day to fly to Portugal from Washington, D.C.. The lowest ticket price found for a Monday departure recently was $750. 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 Friday, with ticket prices averaging around $890.

Our most recent data shows that the best time of day to fly to Portugal is in the afternoon. Flights from Washington, D.C. to Portugal during this time can be as low as $761. In the evening is when there is more demand to fly to Portugal, so prices are often more expensive at around $846 per ticket.

Fly from Washington, D.C. Dulles Intl to Lisbon Humberto Delgado for the best Washington, D.C. - Portugal flight prices

You are more likely to see cheaper flights to Portugal from Washington, D.C. when booking weeks ahead of your departure date. In general, you can expect to find flights to Portugal for around $940 when searching weeks out. However, flight prices might be lower outside of this timeframe. For example, people recently found flights to Portugal from Washington, D.C. for as low as $826 on momondo.

United Airlines, Delta, and KLM are the most popular carriers operating from Washington, D.C. to Portugal

TAP AIR PORTUGAL, United Airlines and Lufthansa are the top three most popular airlines that fly to Portugal from Washington, D.C. according to our data. TAP AIR PORTUGAL is the first choice among our users, with 80% of people opting to fly with this airline when traveling to Portugal. Keep in mind that there are 12 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 Washington, D.C. and Portugal have experienced a delay on any given week. The average delay length over the past 12 months has been 146 minutes.

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

Saturday is statistically the day of the week which experiences the fewest number of delays on this flight route. Friday 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 26% of their flights experiencing any sort of delay.

As of April 2026, 4 flights take off from Washington, D.C. and land in Portugal each day. The most common flight departure time for this route is 10:00PM, with 88% of daily flights taking off in the evening.

As of April 2026, 33 flights take off from Washington, D.C. and land in Portugal each week. The most common flight departure day for this route is Mon, with 18% of weekly flights taking off on this day.