When using your private MitID, you use the same MitID (user ID and authenticator e.g. MitID app) when you log in as a private person and business user.
When you use a separate MitID, you have one MitID for private use and one separately for business use. When you use a separate MitID, you have a separate user ID.
Your private data and your organisation’s data are always separate. No matter which solution you may choose.
Read more about logging in with MitID Erhverv