They were due to meet Monday with Portuguese President Anibal Cavaco Silva and attend a state banquet at the presidential "pink palace." On Tuesday Prince Charles was to visit Evora, a city in Portugal's southeast, and meet with business leaders.
The royal visit comes as Portugal is in the grip of a political and financial crisis that many expect will force it to seek an international bailout like Greece and Ireland.
Charles also has plenty on his mind - his eldest son Prince William is due to marry Kate Middleton on April 29 in London.