Stegesund-Hästholmen is situated in Vaxholm Municipality and Stockholm County.

Hästholmen (to the west) and Stegesund (to the east) are separated by an artificial channel, constructed in 1899, and connected by a bridge.

[citation needed] To the north, west and south, Stegesund-Hästholmen is separated from the islands of Resarö, Edholma and Vaxön by the winding northern section of the Kodjupet strait, whilst to the east it is separated from the island of Skarpö by the much narrower Stegesundet strait.

The artificial channel between Stegesund and Hästholmen is only navigable by very small boats, such as dinghies and canoes.

It is served throughout the year by passenger ships of the Waxholmsbolaget, which call at either the Vikingsborg pier (on Hästholmen) or the Stegesund pier (on Stegesund), providing a connection to Vaxholm town and Stockholm city.