Learn how to write the best donation request letters to secure support for your nonprofit, including six templates to get started. In this post, I'm breaking down how to write a donation letter.This is the simplest online donation form template that you can use without any code requirement and accept donations in the easiest way. Instructions: Use the templates, or a similar form, on pages 2 and 3 to document inkind contributions. Inkind. Include the nonprofit's EIN so the the donor can to check the charity's tax-exempt status with the IRS. Nonprofit fundraising letter template. How to fill out the California Silent Auction Donation Form? There is no official IRS form that the exempt organization has to complete. When does the nonprofit need to send the written acknowledgment letter to donors? The concept is straightforward: donors fill out the form, provide their payment and basic information, and submit their contributions.