When you donate, the DGR will usually issue you with a receipt, but they don't have to. You can only claim a tax deduction for gifts or donations to organisations which are deductible gift recipients (DGRs).How much in donations can I claim on tax without receipts? How much can I claim without receipts? Learn how to lower your income tax while supporting charity. Discover essential tips for tax season and try our donation tax calculator. Tax deductible donations give your refund a boost.