Sandsøya (Norwegian) or Sáhtiidsuolu (Northern Sami) is an island in Harstad Municipality in Troms county, Norway. The 10.8-square-kilometre (4.2 sq mi) island lies east of the island of Grytøya and southeast of the island of Bjarkøya. The highest point on the island is the 212-metre (696 ft) mountain Veten. In 2017, Sandsøya had 91 inhabitants.