It is necessary to specify a reason if a change of given name or middle name is requested. Reasoning is also required when change in surname that is not linked to fathers or mothers name or a family name.
Full name is displayed in passports, certificates etc.
Name change is only allowed once unless in special circumstances.
After name changing it would be desirable to apply for new identities, for example passport and drivers license. Registers Iceland points out that publishing new passport because of name changing requires fee.