*Club domestic league appearances and goals, correct as of 15:28, 30 June 2024 (UTC) ‡ National team caps and goals, correct as of 10:54, 11 June 2022 (UTC)
In November 2012 Nilsson was handed his first professional contract by GIF Sundsvall.[1]
In February 2016 he signed a five-year contract with IF Elfsborg for a fee around €500,000 (5 million SEK).
In July 2019, Nilsson joined 2. Bundesliga side Arminia Bielefeld having agreed a three-year contract. The transfer fee paid to Elfsborg was estimated at €400,000.[2]
In June 2022, Nilsson agreed to a free transfer to St. Louis City SC. He joined the club in July 2022 and the club itself will begin playing in the MLS in 2023.[3]