The internship offer letter should include the start and end dates of the internship, as well as the number of working hours per week. In this article, you'll find guidelines to help you create your own letters along with offer letter templates you can use to hire people more quickly.An internship offer letter is a written document that formally offers an internship to a potential intern. Download a sample template for free. In the formal offer letter, provide comprehensive details about the position, compensation, benefits, and other pertinent terms. You will need a written offer letter from the company prior to registering your co-op or internship with Georgia Tech. When you sign an internship offer letter, that means you have accepted the offer. I'm writing to you regarding the marketing role that opened up at Hart Marketing recently. My name is ______ and I am writing to let you know of my interest in the Financial Analyst internship with Wells Fargo.