Sabang is a city in Aceh province, Indonesia consisting entirely of Weh Island and several smaller islands off the northern tip of Sumatra. The administrative centre of the city is located 17 kilometres (11 mi) north of Banda Aceh. The city covers an area of 122.13 square kilometres (47.15 sq mi) and had a population of 43,391 in the 2020 census although that total was subsequently adjusted to 41,197; the official estimate as at mid 2023 was 43,527. Sabang is known as the northernmost and westernmost city of Indonesia. It also has by far the smallest population of any city in Indonesia.

In Indonesian law, the term "city" is generally defined as the second-level administrative subdivision of the Republic of Indonesia, an equivalent to regency. The difference between a city and a regency is that a city has non-agricultural economic activities and a dense urban population, while a regency comprises predominantly rural areas and is larger in area than a city. However, Indonesia historically had several classifications of cities.