# What the CRA requires in a mileage log, and which vehicle receipts count

> A self-employed Canadian can deduct the business share of vehicle costs, such as fuel, insurance, repairs, licence fees and lease or loan interest, on line 9281 of Form T2125. The share is business kilometres divided by total kilometres for the year, which the CRA expects to see backed by a logbook recording the date, destination, purpose and distance of each business trip. Driving between home and a regular workplace counts as personal. The vehicle itself is claimed through capital cost allowance.

Source: https://simpleloonie.ca/guides/vehicle-expenses-and-mileage-log
Published: 2026-09-26 · Last reviewed: 2026-09-26

## Key facts

- **T2125 line:** 9281, motor vehicle expenses (not including CCA)
- **Business share:** Business km ÷ total km for the year
- **Logbook records:** Date, destination, purpose, kilometres
- **Simplified log:** One full base year, then a three-month sample
- **Commuting:** Home to a regular workplace is personal
- **The vehicle itself:** Capital cost allowance, classes 10 or 10.1

## How much of my car expenses can I deduct?

The business-use share, and only that. Add up every vehicle cost for the year, then multiply by business kilometres divided by total kilometres. If you drove 20,000 km and 8,000 km were for business, 40% of the year's fuel, insurance, repairs and other running costs is deductible.

*Vehicle costs and where they go*
| Cost | Deductible share | Where it goes |
| --- | --- | --- |
| Fuel and oil | Business-use % | Line 9281 |
| Insurance | Business-use % | Line 9281 |
| Maintenance and repairs | Business-use % | Line 9281 |
| Licence and registration | Business-use % | Line 9281 |
| Interest on a car loan | Business-use %, subject to a monthly cap | Line 9281 |
| Lease payments | Business-use %, subject to a monthly cap | Line 9281 |
| Parking for a business trip | In full | Line 9281 |
| Buying the vehicle | Business-use % of the CCA | Capital cost allowance |

The caps on loan interest, lease payments and the cost of a passenger vehicle are set by the Department of Finance and updated from time to time, so check the current figures in the T4002 guide before claiming a vehicle that costs more than an ordinary car.

## What does the CRA require in a mileage log?

A record of every business trip, kept as you go, plus the odometer reading at the start and end of the year. Each trip needs four things.

- The date of the trip.
- The destination — a client's address or a supplier's name, not just a town.
- The business purpose, in a few words.
- The kilometres driven.

> **A reconstructed log is weak evidence.** A log written up in April from memory and a calendar is the thing reviewers are most sceptical of. A note on your phone at the end of each trip is enough, as long as it is made at the time.

## Do I have to keep a mileage log all year, every year?

No. The CRA accepts a simplified approach: keep a full logbook for one complete year to establish a base year, then in later years keep a log for a representative three-month sample period. The sample is scaled against the same three months of the base year to estimate the full year.

The CRA's own worked example: a base year shows 49% business use overall and 46% for April to June. A later year's April-to-June sample shows 51%. The estimated business use is 51% ÷ 46% × 49%, about 54%. The method only holds while the estimate stays within 10 percentage points of the base year — here, between 39% and 59%. Outside that range, the sample only supports the three months it covers.

## Is driving from home to work a business trip?

Not if you are driving to a regular place of business. The trip between home and your usual office, shop or worksite is personal commuting, however far it is. Trips from there to clients, suppliers and job sites are business.

If your home is your principal place of business, trips from home to clients and suppliers are generally business trips, because there is no commute to subtract. This is one of the less obvious consequences of qualifying for the home-office deduction.

## Which vehicle receipts should I keep?

Every one, for the whole vehicle, not just the business share: fuel, repairs, tires, insurance, registration, parking, the loan or lease statement and the purchase agreement. The business-use percentage is applied to the total, so the total has to be supported.

Fuel receipts are the highest-volume receipt most self-employed people collect, and thermal paper from a pump is the first to fade. SimpleLoonie reads each one, records the GST/HST separately so the tax can be claimed at the business-use share, and files it under a vehicle category, so the year's total for line 9281 is one number in an export. The logbook itself and the percentage are yours to keep and apply.

## Frequently asked questions

### Can I deduct 100% of my car expenses if I am self-employed?

Only if the vehicle is used exclusively for business, which is rare and hard to support for a car that is also your personal vehicle. Normally you deduct the business-use percentage — business kilometres divided by total kilometres — of each running cost.

### Can I use the CRA's per-kilometre rate instead of actual expenses?

Not as a self-employed person claiming on the T2125. The per-kilometre rates are for employers paying tax-free allowances to employees. The self-employed deduct the business share of actual costs, supported by receipts and a logbook.

### Is parking deductible in full?

Parking fees for a business trip are deductible in full rather than at your business-use percentage. Parking at your regular place of business, or for personal use, is not deductible.

### What happens if I do not keep a mileage log?

The CRA can reduce or deny the vehicle claim, because the business-use percentage is unsupported. Calendars, invoices and fuel receipts help reconstruct it, but a log kept at the time is far stronger evidence.

### Can I claim the GST/HST on vehicle expenses?

A GST/HST registrant can generally claim input tax credits on vehicle running costs in proportion to business use. Special rules apply to the purchase of a passenger vehicle, so confirm the treatment with your accountant before claiming the tax on the vehicle itself.

## Sources

- [Canada Revenue Agency — Motor vehicle expenses](https://www.canada.ca/en/revenue-agency/services/tax/businesses/small-businesses-self-employed-income/business-income-tax-reporting/business-expenses/motor-vehicle-expenses.html)
- [Canada Revenue Agency — Motor vehicle records](https://www.canada.ca/en/revenue-agency/services/tax/businesses/topics/sole-proprietorships-partnerships/business-expenses/motor-vehicle-expenses/motor-vehicle-records.html)
- [Canada Revenue Agency — Guide T4002, Chapter 3: Expenses](https://www.canada.ca/en/revenue-agency/services/forms-publications/publications/t4002/t4002-5.html)