The login methods represent different security levels, and this will thus affect which services and profile settings you will have access to.
If you try to access a service while being logged on with a security level which is too low, you will see a message telling you to log on again, with a higher security level.
Security level 4 – Login with BankID, Buypass, Commfides and BankID on Mobile (via ID-porten)
If you log on with Commfides, BankID, BankID on Mobile or Buypass, you are logged on with the highest security level. You will need this security level for instance if you wish to sign the form for changing your account number for refunds from NAV or send an official receivers report.
Security level 3 – Login with MinID (via ID-porten) or enterprise certificate
If you choose to log on with PIN codes for MinID (letter or SMS), you will access the second highest security level in Altinn, and will have access to most services. This security level is needed for instance in order to read the reports K27 and K37 from NAV, and in order to send the form Samordnet registermelding (BR-1010) to The Brønnøysund Register Centre. eIDAS and enterprise certificate will also give you access to security level 3.
Security level 2 – Login with single-session PIN code (letter or SMS) from Altinn
With a single-session PIN code from Altinn, you log on with security level 2. You will access a number of services, and can change the information in My Profile.
Security level 1 – Login with only a password
If you log on with only a password, you will have access to a limited number of services in Altinn. You will not be able to change the mobile telephone number in My Profile in this security level.
Security level 0 – Login without national identity number/D-number
If you do not have a national identity number/D-number, you will only be able to log on with a user name and a self-registered password. Only a very limited amount of services will be available through this security level.