Im a volunteer driver for a nonprofit providing transport to stores/appointments. Im reimbursed for my mileage at less than the federal rate of 65 cents. Is this taxable?

[MonikaK1]

Volunteers who drive their vehicles when they perform work on behalf of a nonprofit are restricted in tax law to deducting only 14 cents per mile, a rate set in statute decades ago. Volunteers who are reimbursed by the charity for the miles they drive are technically liable for income taxes on any amount over 14 cents per mile. 

The 65-cent rate is for business mileage. See here for the IRS mileage rate announcement for 2023.