I always included what they had donated and a description of the programs that would benfit from the donation. We never gave them a thank you note when we got the donation. Typically, we sent the businesses and individuals letters about two weeks after the event so we could tell them how many people attended and how much money we raised.
I'm looking for some examples of donation thank you letters that our raffle volunteers could fill out on the spot and give to local businesses that donate items or services to our PTO. I know that we should put it on letterhead with the PTO's tax-exempt number but what else should I include?