Statistics Portugal publishes the first post-census Estimates of Resident Population in Portugal for the years 2020 and 2021, based on the provisional results of the 2021 Census, as announced in the Press Release of June 14th, 2021, regarding the Portugal Resident Population Estimates 2020. This is an ad hoc exercise of resident population estimates, which will be revised after the definitive results of the 2021 Census are available.

The resident population in Portugal, as of December 31, 2021, was estimated at 10,352,042 people, 19,578 fewer people than in 2020.

The population decrease in 2021 resulted from a net migration of 25,642 people, which did not counterbalance the negative natural balance, that decreased in 2021 to -45,220 (-38,828 in 2020). These results translated into a crude rate of increase, a crude rate of net migration and a crude rate of natural increase of -0.19%, +0.25% and -0.44%, respectively.

In 2021, the ageing index, which compares the population aged 65 and over (elderly population) with the population aged 0 to 14 (younger population), reached the value of 184.9 elderly people for every 100 young people (180.6 in 2020).