A parent exercising sole custody may make an agreement with his/her spouse that they shall exercise joint custody of a child if they are married or have been registered in a cohabitation with Registers Iceland for at least one year.

Procedure and accompanying documents to be submitted are the same as when parents agree on a change of custody, but the district commissioner shall also seek the opinion of the non-custodial parent of the child.

More information on the custody of stepparents can be found here.