Mileage Tracking: The Deduction Most People Underclaim
Business driving is deductible at a fixed rate per mile, and DynaTax AI applies the correct IRS rate for the year and trip type automatically. The hard part was never the arithmetic — it is having a log at all. This guide covers what qualifies, what does not, and what the IRS expects you to have written down.
Why Mileage Is Worth Logging
At the 2026 business rate, 5,000 business miles is a deduction of roughly $3,625. That is not a rounding error on a small business return, and it is routinely left on the table for one reason: nobody wrote the trips down at the time.
Logging a trip takes seconds while you still remember where you went. Reconstructing a year of driving in March does not work, and an unsupported estimate is exactly the kind of number that gets disallowed.
The IRS Rates by Year
Rates change annually, and DynaTax AI applies the one that matches the date of the trip — not today's rate. A trip you log late still gets its own year's figure.
| Trip type | 2024 | 2025 | 2026 |
|---|---|---|---|
| Business | 67.0¢ | 70.0¢ | 72.5¢ |
| Medical | 21.0¢ | 21.0¢ | 20.5¢ |
| Moving | 21.0¢ | 21.0¢ | 20.5¢ |
| Charity | 14.0¢ | 14.0¢ | 14.0¢ |
The charity rate never moves, which surprises people. Business and medical rates are set by the IRS each year from cost data; the charitable rate is fixed in statute, so it takes an act of Congress to change and has sat at 14¢ for decades.
What Counts as a Business Trip
Deductible business driving includes:
- Driving to a client, a customer, or a job site
- Travelling between two work locations in the same day
- Trips to buy supplies, equipment or inventory
- Driving to the bank, the post office or your accountant on business
- Travel to a business conference or training
- Driving from a home office to a work location — if the home office is your principal place of business
The Commuting Rule
The trap worth understanding: commuting is never deductible. Driving from home to your regular workplace is personal, no matter how far it is, how early you leave, or that you took work calls on the way.
What changes the answer is where your business is based. If your home office is your principal place of business, the first drive of the day is not a commute — it is travel between your office and a work location, and it counts.
What to Record
The IRS expects a contemporaneous record — written near the time of the trip, not reconstructed later. For each trip, log:
- The date
- Miles driven
- Where you went
- The business purpose — a few words, but real ones
The purpose field is the one that decides audits. “Business” explains nothing. “Site visit, Henderson kitchen remodel” is a record. It takes the same three seconds and it is the difference between a deduction that stands and one that does not.
Where to Find It
- Business owners: Expenses → Mileage.
- Tax professionals: open the client, then Bookkeeping → Mileage.
Frequently Asked Questions
Can I claim mileage and my actual car costs?
No — the standard mileage rate and the actual-expense method are alternatives, not additions. The rate already covers fuel, maintenance, insurance and depreciation. Claiming both for the same vehicle double-counts. Your accountant can work out which method is better for your situation.
What about tolls and parking?
Those are deductible separately, on top of mileage — they are not built into the rate. Log them as ordinary business expenses.
I use one car for business and personal driving.
That is the normal case. Log the business trips only — the standard mileage method works trip by trip, so a mixed-use vehicle needs no allocation, just an honest log.
I forgot to log trips for a whole month.
Reconstruct what you genuinely can support — a calendar entry, an invoice, a job record that puts you at a place on a date. Do not invent round numbers. A smaller, defensible claim is worth more than a larger one that collapses under a question.