In this article, we discuss how to write a business proposal letter and we offer sample letters and templates you can use as a guide. This website has a great example of a business letter format.Finally, remember your goal. Instantly draft and send a business proposal template to establish the terms and conditions between your business and clients. A proposal letter is a professional document that introduces your business ideas to an important recipient who holds a decisionmaking role. Does the project support the mission of the University of Arizona? A business proposal letter is a document sent to a prospective client or partner, introducing your services or requesting an opportunity. All notifications are on a courtesy basis only. Business Lease Proposal Template imgus.