What Your CRA Mileage Log Actually Needs to Show

What every trip entry needs

For each business trip, CRA expects your logbook to record:

• The date
• Your destination
• The purpose of the trip (who you saw or what you did there)
• The number of kilometres driven

On top of the trip-by-trip details, record your vehicle's odometer reading at the start and end of your fiscal period — that's what lets you calculate total kilometres driven for the year, which you need to work out your business-use percentage.

Full logbook vs. simplified logbook

CRA has two accepted approaches:

• Full logbook: track every business trip, all year, every year. The most reliable method, and the only one available in your first year of claiming vehicle expenses.
• Simplified logbook: once you've kept a full logbook for one complete base year, later years only need a 3-month sample. You don't use that sample's percentage directly — you compare it to the same three months from your base year, and scale your base year's annual percentage by the ratio between them. If the sample period comes out more than 10 percentage points different from the base year's, the shortcut doesn't apply for that year and you're back to a full logbook.

How long to keep it

Keep your mileage log — like your other business records — for six years from the end of the last tax year it relates to, not six years from the date of the trip.

Recording date, destination, purpose, and distance for every trip as you go is far more reliable than reconstructing months of driving from memory at tax time — which is exactly what a running log is for.