The aim of this paper was to describe the study design, data collection procedure and participation of the population-based study "Sámi Health on Equal Terms" (SámiHET) conducted among the Sámi in Sweden in 2021. A Sámi sample was constructed, drawing from three pre-existing-registers: the Sámi electoral roll, the reindeer mark register and the "Labour statistics based on administrative sources" register to identify reindeer herding businesses. All identified persons aged 18–84 were invited to participate during February–May 2021. Among the 9,249 invitations, 3,779 answered the survey (participation rate of 40.9%). More women than men participated, and the age group 45–64 was the most common in both sexes. Around 10% of participants were in the youngest group. A majority of participants were residents of Norrbotten (48%), while almost one fourth were living outside Sápmi (22%). SámiHET has been demonstrated to be a feasible and cost-effective way of investigating health and living conditions among the Sámi in Sweden, providing information easy to compare with Swedish data. The knowledge to be produced may be used to inform policy to guide and improve Sámi health, thus contributing to realising the equal health rights of the Indigenous Sámi in Sweden.