Short answer
To reconstruct a mileage log, start from records made at the time: location history such as Google Maps Timeline, calendar entries, invoices and receipts. Take the trips, dates and miles from those records, add the business purpose of each trip, total the year and check it against your odometer. Never fill gaps from memory alone.
What do you need to reconstruct a mileage log?
Four kinds of records, from the strongest to the weakest:
| Record | What it proves | Where to find it |
|---|---|---|
| Location history | Date, times, places, miles of each drive | Google Maps Timeline export on your phone |
| Calendar and appointments | Which client, which day | Google or Outlook calendar, booking tools |
| Invoices, work orders | Business purpose of a visit | Your invoicing or accounting software |
| Odometer readings | Total miles of the year | Service records, inspection reports, photos |
How do you reconstruct it, step by step?
- Export your history. Export Google Maps Timeline from your phone and check which months it covers.
- List every drive of the year, business and personal: the IRS asks for business miles and total miles.
- Mark the business places: clients, job sites, suppliers. Your regular workplace is commuting, not business.
- Write a purpose for each business place or trip, from your invoices or calendar.
- Check the total against odometer readings near January 1 and December 31.
- Keep the sources with the log: the export, the invoices, the readings.
The Google Maps Timeline mileage log does steps 2 to 5 on your device: it lists the drives, lets you mark places once, and adds parking, tolls and odometer readings.
Rebuilding by hand instead? Our mileage log template has the columns to fill.
How do you handle months with no record?
Leave them out unless another record made at the time shows the trip. Miles your odometer shows but no record explains are not business miles: count them as personal. A shorter log you can back up is worth more than a complete one you cannot.
How should you present a reconstructed log?
- Say how it was built and from which records, on the first page.
- Keep the original times and distances; do not round them up.
- Include every trip, so business, commuting and personal miles add up to the total.
- Show it to your tax professional before you file or answer the IRS.
Common questions
How long does it take to reconstruct a year of mileage?
By hand, from a calendar and receipts, many hours per year. From a Google Maps Timeline export, the trips, times and miles are already there: what remains is marking which places were for work and writing the purposes, usually under an hour.
Can I use Google Maps directions to estimate the miles?
For a trip you know happened but that no record shows, a route distance is a reasonable figure, as long as the trip itself is supported by another record made at the time (an invoice, an appointment). Say in the log which distances came from a route estimate.
Should a reconstructed log say it was reconstructed?
Yes. Presenting a rebuilt log as if it had been kept day by day is what damages credibility. State how it was built and keep the source records with it.