Banks and other financial institutions may demand a “proof of verification deposit” form to be filled in and sent to the borrower’s bank for process completion. how do lenders verify bank statements A proof of deposit may also require the borrower to provide a minimum of 2 consecutive months’ bank statements. During the loan approval process, if you’ve ever wondered “Why is verification of bank statements for mortgages required?” the answer is to reduce the chances of people with fake documents acquiring funds for illegal activities.