Pétur Marteinsson

Marteinsson is an operation manager in Reykjavík, living in Vesturbær, raised in Breiðholt and Ártúnsholt (local neighborhoods in the city of Reykjavik). After his professional football career abroad, Marteinsson lived with his family in several cities, including Stockholm, Oslo, Stoke-on-Trent, and Boston. These experiences contributed to his interest in urban planning and its role in shaping urban environments. Since 2007, when returning home to his native Iceland, Marteinsson has built small and medium-sized businesses with the goal of improving local community services and enhancing human life in Reykjavik. These include Kex Hostel and Kaffihús Vesturbæjar (Kaffi Vest). He has also been involved in the development of housing aimed for first time buyers through his urban development firm Borgarbragur. Marteinsson has also been involved as advisor in planning sports facilities within local neighborhoods and a new national stadium in Reykjavik. Since 2024, Marteinsson has been employed with OZ Sports, an infrastructure provider for sports broadcasting.

In early January 2026, Marteinsson declared his candidacy to lead the Social Democratic Alliance, Samfylkingin, in the primaries for the May 2026 municipal elections in the City of Reykjavik.

Marteinsson was born in Reykjavík and started his career in Fram. He moved to Swedish club Hammarby IF in 1996 where he was a great success. A sought-after defender, Marteinsson was bought by the Norwegian club Stabæk, coached by Anders Linderoth. In November 2001, he moved on to English club Stoke City, joining up with a number of fellow Icelandic players. He made his debut against Peterborough United in January 2002. He made just two more appearances during the 2001–02 season and when Guðjón Þórðarson was sacked at the end of the season Marteinsson struggled to get a look in with new manager Steve Cotterill and then Tony Pulis. Marteinsson made 18 league appearances for Stoke scoring twice against Bradford City in 2002 before being released in September 2003. He returned to Hammarby where he spent three years and made 48 appearances for "Bajen". In October 2006, KR Reykjavik announced they had signed Marteinsson for the 2007 Icelandic premier league season, a move which saw Marteinsson return to his native Iceland to finish his career in 2008. In his last season he won a cup.

Marteinsson was raised in Breiðholt and Árbær (local neighborhoods in the city of Reykjavik) and is the son of former Icelandic international player Marteinn Geirsson and Hugrún Pétursdóttir. Marteinsson is married to Unnur Anna Valdimarsdóttir, professor at the University of Iceland. They have one daughter.