Malolos is a coastal component city in the province of Bulacan. It serves as the provincial capital.

The city has a land area of 67.25 square kilometers or 25.97 square miles which constitutes 2.42% of Bulacan's total area. Its population as determined by the 2020 Census was 261,189. This represented 7.04% of the total population of Bulacan province, or 2.10% of the overall population of the Central Luzon region.

Based on these figures, the population density is computed at 3,884 inhabitants per square kilometer or 10,057 inhabitants per square mile.