Aveiro ( ) is a city and a municipality in Portugal. In 2021, the population was 80,880, in an area of 197.58 square kilometres (76.29 sq mi): it is the second most populous city in the Centro Region of Portugal. Along with the neighbouring city of Ílhavo, Aveiro is part of an urban agglomeration that includes 120,000 inhabitants, making it one of the most important populated regions by density in the North Region, and primary centre of the Intermunicipal Community of Aveiro and Baixo Vouga. Administratively, the president of the municipal government is José Ribau Esteves, elected by coalition between the Social Democratic Party and the Democratic Social Centre, who governs the ten civil parishes.

The Central Region or Central Portugal is one of the statistical regions of Portugal. The cities with major administrative status inside this region are Coimbra, Aveiro, Viseu, Caldas da Rainha, Leiria, Castelo Branco, Torres Vedras, Tomar, and Guarda. It is one of the seven Regions of Portugal. It is also one of the regions of Europe, as given by the European Union for statistical and geographical purposes. Its area totals 28,462 km2 (10,989 sq mi). As of 2011, its population totalled 2,327,026 inhabitants, with a population density of 82 inhabitants per square kilometre.