Attach the IRS Form 990 or Form 990EZ for the preceding fiscal year. The IRS may require small tax-exempt org.Understand what a charitable donation is and how to claim a tax deduction without a tax receipt with IRS Form 8283. To obtain a letter of authorization (LOA), a nonprofit volunteer health clinic must apply online through the Georgia Tax Center (GTC). Generally, you may deduct up to 50 percent of your adjusted gross income, but 20 percent and 30 percent limitations apply in some cases. See Sample C below. 2. Include Volunteer Activity. There are two aspects to consider when discussing inkind gifts and taxes. On the donors' side, the main concern is tax deductibility. Operation of a Georgia nonprofit corporation with IRS recognition as a Section.