A proof of income letter, otherwise known as a salary verification letter, is an official document that proves you're currently employed and earning a salary. Use these letters to order your credit report directly from the big four credit reporting agencies.Be sure to include copies of the identification documents. This letter is to confirm our phone conversation during which you accepted our offer of the Building Maintenance Manager position at Michigan State University. You may register up to the start of classes each semester. Once you click the Register link, you will be redirected to the MyCreds registration page. Search Results for: 【Site: Sig8.