Mileage logbook rules for tax deductions
Keep a mileage log that shows when you drove, where you went, why the trip was for business, and how many miles you drove. Also keep your annual vehicle mileage totals. Records made as you go are stronger than a log rebuilt months later.
U.S. federal tax rules · Updated August 18, 2026
← Back to Is mileage tax deductible?
On this page: The 5 required elements · Contemporaneous records rule · Paper log vs mileage app · Annual records to keep · What an inadequate log looks like · Example entry · How long to keep records · IRS sources · Related lookups · FAQ
What to include in your mileage log
For each business trip, keep the basic details below. Keep your annual total mileage separately so you can support the business-use information on your tax return.
For each business use, record:
- Date of the trip or use
- Destination/place of the business travel
- Business purpose, unless it is clear from the surrounding circumstances
- Miles or other evidence of the amount of vehicle use
Also keep annual vehicle information sufficient to establish total, business and commuting/personal use as required by Schedule C or Form 4562.
When to record your mileage
Record trips while the details are still fresh. IRS Publication 463 says records made at or near the time of the trip carry more weight. A weekly log can still count as timely.
- Weekly can be timely: Publication 463 specifically says a log maintained weekly that accounts for use during the week can be considered timely.
- Avoid waiting until tax time: A log rebuilt months later from memory is much harder to support than records kept during the year.
- Incomplete records are not automatically hopeless: Publication 463 describes circumstances in which an incomplete element can be supported by a specific statement plus other sufficient evidence.
Paper logbook vs mileage tracking app
| Method | Can support timely records? | What to watch |
|---|---|---|
| Paper logbook | Yes | Enter trips consistently and keep enough detail to prove purpose and miles |
| Spreadsheet or notes app | Yes | Update it regularly; a weekly log can be timely |
| GPS mileage tracking app | Yes | Review automatic drive detection, classify trips correctly and add business-purpose details when needed |
| Year-end reconstruction from memory | Weaker evidence | Support it with contemporaneous calendars, invoices, GPS data or other evidence where available |
| Calendar alone | Supporting evidence | Often does not establish the miles or complete business-use facts by itself |
MileIQ — Automatically track drives and organize mileage records
MileIQ can detect and record drives automatically, lets you classify business and personal trips, and can export mileage reports. Review trips and add the business purpose when needed before using the report with your tax records.
Annual records to keep alongside the mileage log
- Odometer reading January 1 (or the date you started using the vehicle for business)
- Odometer reading December 31 (or the date you stopped using it)
- Total miles for the year — calculated from the odometer readings
- Total business miles for the year — summed from individual log entries
- Business-use percentage — business miles ÷ total miles × 100
Mileage log mistakes to avoid
- No specific business purpose or surrounding facts tying the trip to the business
- Rounded annual estimates with no trip-level support
- Ordinary commuting included as business mileage
- App data left unclassified or automatically classified without review
- No reliable way to reconcile business miles with total vehicle use when the return requires those totals
- Expense receipts without records establishing the business-use percentage under the actual method
Example: Three clear mileage log entries
| Date | Destination | Business purpose | Miles |
|---|---|---|---|
| 2026-03-04 | 123 Main St, Bellevue | Project kickoff — Acme Corp | 22 |
| 2026-03-07 | Home improvement supplier | Materials for Smith project | 8 |
| 2026-03-11 | Downtown conference center | Industry trade show / prospecting | 15 |
These entries show date, place, business purpose and miles. Keep annual vehicle-use totals and any other supporting information required for your return separately.
How long to keep mileage logs
A common rule is to keep tax records for at least three years after you file the return. Some situations require longer. Keep vehicle purchase, basis, and depreciation records longer when they can affect later tax years or a future sale.
Keep records as long as they may be material to an open tax year or to the basis/depreciation history of the vehicle.
TurboTax — Use mileage records when preparing Schedule C
TurboTax accepts mileage reports from tracking apps, guides you through Schedule C vehicle questions, and confirms you have checked "written evidence" on the return.
FAQ
What does a mileage log need to include for IRS purposes?
For each business trip, keep the date, destination, business purpose, and miles driven. Also keep your annual total mileage so you can support the business-use information on your tax return.
Do I have to record every trip the same day?
Not necessarily. IRS Publication 463 says records made at or near the time of the trip carry more weight, and a weekly log can still count as timely. The longer you wait, the harder it is to prove the details accurately.
Can I recreate a mileage log at tax time?
You can sometimes use other records to help fill gaps, but a log rebuilt months later from memory is much weaker than records kept during the year. Calendars, invoices, GPS history, and similar records may help support missing details.
Can I use a mileage tracking app instead of a paper log?
Yes. A mileage app can help record trips and distance automatically. You still need to review the trips, mark business versus personal driving, and add the business purpose when needed.
What happens if my mileage records are incomplete?
The IRS can reduce or deny vehicle deductions that are not supported well enough. Calendars, invoices, GPS data, and other records may help fill gaps, but keeping a clear mileage log during the year is much safer.
← Back to Is mileage tax deductible?
Last reviewed: August 18, 2026