He spent the majority of his professional career at IFK Göteborg, but also represented Esbjerg fB in Denmark and Lokeren in Belgium.

Söder was signed for the youth team of the Swedish champions IFK Göteborg in December 2007, but soon began to train and play with the senior squad.

Only eleven days later, he made his first Allsvenskan goal for the club, securing three points against Djurgårdens IF by scoring 2–1 in the 91st minute.

After his debut season he was awarded Newcomer of the Year at the annual Fotbollsgalan, beating Sebastian Rajalakso, Rasmus Jönsson and Joel Ekstrand.

[1] After six seasons in IFK Göteborg, Söder decided to move to Danish side Esbjerg fB on 22 August 2014.

[5] On 24 February 2019, he was voted as 2018 Årets ärkeängel (Archangel of the Year), an award given to a player who is considered to have shown great loyalty to the club.

[15] After his successful 2019 season, Söder was called up to the national team by Janne Andersson for the friendly games against Moldova and Kosovo in January 2020.