It is almost 14 kilometres (8.7 miles) in length and its lagoon, known as Te Moana, is totally enclosed by the coral reef.

Sikaiana is a remote tropical coral atoll located at latitude and longitude 8°25′0″S 162°52′0″E, over 200 kilometres (125 miles) from any other islands.

Administratively, Sikaiana is governed as an outlying region of Malaita Province in Solomon Islands.

Sikaiana's population is approximately 300 people of Polynesian descent—not of the Melanesian descent prevalent in the main Solomon Islands.

In 1996, some Stewart Islands residents applied to register to vote in a plebiscite limited to Native Hawaiians.