Porirua City had a population of 56,559 at the 2018 New Zealand census, an increase of 4,842 people (9.4%) since the 2013 census, and an increase of 8,013 people (16.5%) since the 2006 census. There were 17,838 households. There were 27,585 males and 28,974 females, giving a sex ratio of 0.95 males per female. Of the total population, 13,443 people (23.8%) were aged up to 15 years, 11,127 (19.7%) were 15 to 29, 25,419 (44.9%) were 30 to 64, and 6,570 (11.6%) were 65 or older. Figures may not add up to the total due to rounding.