What kind of information can the landlord request before you enter into a tenancy agreement?

The Tenancy Act does not have rules about what kind of information the landlord may or may not request, but section 1-8 forbids discrimination.

When renting out housing, it cannot be taken into consideration sex, pregnancy, faith, religion, disability, sexual orientation, gender identity, gender expression or age.

This means that the landlord should not request information that could lead to discrimination.

The landlord is permitted to ask for information which entails that you as a tenant is identified, like your Norwegian national identity number. This is because it is information the landlord needs to open a deposit account.