It’s easy to estimate your business mileage, but HMRC wants to see accurate figures recorded as close to the time of the journey as possible. There are a number of apps which can help you with this.
To achieve the precision HMRC is looking for, you need to know where your business journey starts and finishes. That is not necessarily at your home if you are self-employed.
HMRC will argue your work starts when you reach your customer’s site, and any activities performed at your home-office are irrelevant. This prevents you from claiming expenses for travelling from your home to the first customer of the day, but does allow you to claim for journeys between customers.
To claim for business journeys starting from your home, you need to prove your business is truly based there. To support this argument, record the time you spend on working in your home-office, and what you were doing, e.g. contacting suppliers, or drawing up quotes.
Once you have established the number of miles which qualify as business journeys, you can claim 45p for each mile driven up to the first 10,000 miles, and 25p per mile for any additional miles in the tax year. Alternatively, you can claim a proportion of your total motoring expenses that relate to business miles, compared to the total distance you have driven in the year.