Time and Manner of Providing Acknowledgment – You must obtain the written acknowledgment on or before the earlier of the date you file your return for the year you donated the vehicle, or the due date, including extensions, for filing the return. A charity can provide you with a paper copy of the acknowledgment, or it can provide the acknowledgment electronically, such as via an email addressed to you. Do not attach the acknowledg ment to your income tax return; instead, retain it with your records to substantiate your donation. .
