What do you need to include in your donation acknowledgment letter? For best results, write a personal acknowledgment letter with a receipt that includes the IRS-required elements.In that case, all you need to provide in the donation receipt is the name and EIN of the organization, date of donation, and a description of the donated item. Take a look at what makes a good thank you letter for a donation or use one of our provided templates to help get you started. Listed below are examples of how to acknowledge these gifts in a Thank You letter to your donor. 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? A donation acknowledgment letter (sometimes called a donation receipt or thankyou letter) is an email or paper that recognizes a charitable contribution. Sometimes your donation receipt functions as a donor acknowledgement. However, that's not always the case.