Portugal has two timezones. Mainland Portugal and Madeira use Western European Time (WET) in winter (UTC+0) and Western European Summer Time (WEST) in summer (UTC+1). The Azores use Azores Time (AZOT), which is 1 hour behind the mainland (UTC-1 in winter, UTC+0 in summer).
Major mainland cities including Lisbon, Porto, Braga, and Faro follow WET/WEST. Madeira (Funchal) shares the same timezone as the mainland. The Azores are 1 hour behind.
Portugal is the westernmost country in continental Europe, which is why it uses WET (same as the UK). Lisbon and Dublin are at almost the same longitude. The Azores, located 1,500 km off the coast in the Atlantic Ocean, are the westernmost point of Europe and have their own timezone. Portugal and the UK have had an alliance since 1373—the oldest in the world still in force.