Business vs Personal miles

PBG2023 · ‎March 28, 2026

My wife has been teaching yoga as a 1099-NEC for several years, and our former CPA never suggested tracking her mileage and vehicle expenses. Now that I’ve decided to file our taxes, I’ve realized we’ve been missing out on a valuable deduction. However, I’m puzzled by the reason for asking about tracking personal mileage. I noticed that the refund amount changes depending on which radio button I select for the question “I tracked personal miles” (Yes or No). This doesn’t make sense because we know the annual mileage and business miles, so everything else is personal mileage. Does the IRS seriously want a log of each grocery, doctor visit, date night ,etc trips?

MindyB

The IRS doesn't expect a detailed diary of your personal trips, they want to know if you kept a contemporaneous log that proves your business usage.

You must have a record of your total annual mileage (from January 1 and December 31 odometer readings) and a specific log of business trips, which allows personal miles to be tracked by subtracting the business portion from the total.

The refund amount shifts because the tax software disqualifies the deduction if you admit to not keeping these records, as the IRS technically requires "sufficient evidence" to support the claim. To safely claim the deduction, your wife needs to be able to show her teaching schedule or a mileage log that justifies the business miles, the "personal" portion is then just the remaining balance of her total annual driving, and no line-item "date night" log is required.