Mililani is a city located near the center of the island of Oʻahu in Honolulu County, Hawaiʻi, United States. It consists of two census-designated places, Mililani Town, with a population of 28,121 at the 2020 census, and Mililani Mauka, with a 2020 census population of 21,075.

Honolulu County, officially known as the City and County of Honolulu, is a consolidated city-county in the U.S. state of Hawaii. The city-county includes both Urban Honolulu and the rest of the neighborhoods on the island of Oʻahu, as well as several minor outlying islands, including all of the Northwestern Hawaiian Islands except Midway Atoll.