Per IRS Instructions for Form 1098-C Contributions of Motor Vehicles, Boats, and Airplanes:
Caution: You must attach Copy B of Form 1098-C to your income tax return in order to take a deduction for the contribution of a qualified vehicle with a claimed value of more than $500. (If you e-file your return, you must (a) attach Copy B of Form 1098-C to Form 8453 and mail the forms to the IRS, or (b) include Form 1098-C as a PDF attachment if your software program permits.) If you do not attach Copy B of Form 1098-C to your return (or to Form 8453) when required, the IRS will disallow your deduction. Generally, you must also attach Form 8283, Noncash Charitable Contributions, if the amount you deduct for all noncash gifts is more than $500. See the Instructions for Form 8283 for exceptions.
You received Form 1098-C because you donated a motor vehicle, boat, or airplane (“donated vehicle”) to the charity shown on the front of this form. Generally, the charity must furnish this form to you no later than 30 days after the date it sold the donated vehicle (if box 4a is checked) or 30 days after the date of the contribution (if box 5a or 5b is checked). If none of these boxes is checked, you must obtain this form by the due date (including extensions) of your tax return for the year of the contribution (or, if earlier, the date you file that return).
To enter the information from Form 1098-C in the TaxAct program:
If you provide information for the contribution of a vehicle, you will be prompted to print Form 8453 in the filing steps. Attach the supporting documentation to Form 8453 and mail this information to the IRS, as directed in the Federal Electronic Filing Instructions (which can be viewed or printed later in the e-file screens).
Form 8453 and the required forms or supporting documents must be mailed to the IRS within three business days after receiving acknowledgement that your return was accepted. An electronically transmitted return will not be considered complete until a Form 8453 is received by the IRS.
Note that any link in the information above is updated each year automatically and will take you to the most recent version of the webpage or document at the time it is accessed.