What do you need to include in your donation acknowledgment letter? A donation acknowledgment letter (sometimes called a donation receipt or thankyou letter) is an email or paper that recognizes a charitable contribution.It should provide written acknowledgment of donations it receives (known as donation receipts) so that donors may claim a tax deduction for their contribution. When acknowledging these donations, include the name of the donor, the number of shares, the name of the security, and the date when the transfer was completed. What to include in donor acknowledgment letters? To assist you in determining your eligibility to sign an Acknowledgment of Parentage, the following definitions are provided:.