If you deduct vehicle expenses you must maintain TRIPS LOG. The log should contain the date of the trip, purpose, starting point, destination point and km driven. This is a popular expense line that CRA audits. Vehicle expenses are not deductible without the log so don't skip keeping it. There are plenty of apps on the market that make keeping a log very easy. My clients recommend: Milecatcher, Simple Mileage Tracker, TripLog Car Mileage.