Tomakomai is a city and port located in Iburi Subprefecture, Hokkaido, Japan. Though its name implies a small, idyllic town, it is the largest city in the Iburi Subprefecture. As of February 29, 2012, it had an estimated population of 174,216, with 83,836 households and a population density of 310.27 persons per km² (803.60 persons per sq. mi.). The total area is 561.49 km2 (216.79 sq mi).