How long is the MIP (Mortgage in principle) valid for? 15 March 2022 12:51 Updated A Mortgage in Principle (MIP) from us is valid for 90 days, after 90 days you'll need to reapply for an updated MIP Related articles Can I amend an application that's been offered? How long is the mortgage process with Molo? Will this application affect my credit rating? Personal guarantees for Limited Company mortgages