Askim is a town and a former municipality in Indre Østfold municipality in the county of Østfold, Norway. The administrative centre of the Askim municipality was the town of Askim. Askim was established as a municipality on 1 January 1838. Askim is the largest population centre in the Indre Østfold region, with 15,315 inhabitants as of 2012, and serves as a regional center for nine municipalities in the Indre Østfold region.