How To Keep an HMRC Mileage Log Book For Taxes

If you want to receive a mileage allowance, keeping a mileage log will be necessary. How you do that is up to you, but there are things that no matter which format you choose you must record. A customer meeting in another city, a financing discussion at the bank, or a trip to the airport to pick up business partners – many self-employed individuals and regular employees use their personal vehicles for business purposes.

Do you need to keep a mileage log?

A mileage deduction is a great way to save a little extra tax if you use your vehicle for business purposes. However, HMRC will not accept your word for it; to claim this deduction, you must provide proof. In other words, a mileage log book is required and should contain records of all the trips you claim reimbursement for.

You need a mileage log book if: 

• you are self-employed
• You are employed and your employer provides mileage allowance payments
• a sole proprietor
• a partner in a firm
• you use your vehicle for business purposes

In your mileage log, you record how frequently and for how long you drive your vehicle for business and private purposes. As a result, you will be able to figure out exactly how much you drove for business and be reimbursed for it.

There may be some differences in how you keep a log depending on your circumstances. To begin with, you need to figure out whether you are eligible for MAP (Mileage Allowance Payments) or MAR (Mileage Allowance Relief). MAR is provided by HMRC in the form of tax deductions, while MAPs are a reimbursement you receive from your employer.

What to record in your mileage log book

A mileage log book normally covers a period of one year if you are claiming mileage allowance relief at tax time. If you receive reimbursement from your employer, your mileage log should cover whatever period you receive reimbursement for. You should record the following information in your HMRC mileage log:

• Each journey's date
• The purpose (business or personal)
• The origin and destination addresses of your journey including postcodes, as well as the total number of miles driven.
• Any additional information your employer might require, for example, odometer readings.

Keeping a mileage log is often the most efficient method of claiming your mileage allowance, but it does require some effort. Considering how time-consuming this could be when using a logbook, you may want to consider getting a mileage tracker app that can do all of this for you.

How much you can save by keeping a mileage log

It depends on how much you drive your car for business, but any time you forget to log a trip, you are missing out on potential reimbursement. The more you use your mileage log book properly and log every necessary detail, the more likely you are to get the proper reimbursement.

Mileage log formats accepted by HMRC

There are many formats accepted by HMRC for keeping a mileage log book. If you have the time to enter everything manually, you can use an Excel mileage log template, a PDF, a Sheets file or a physical log book. If you are looking for a faster solution, we recommend a mile tracker app as your online logbook. The app can automatically track your trips and will require less time to use.

Other important things to keep in mind for your mileage log

• Each journey must be documented, including the start and end address, the distance travelled, and a mention of the reason for the journey.
• Entries must be legible and clear.
• In case of a lost mileage log book, you should consider changing to a digital solution to avoid this from happening again. Contact HMRC to find out what you should do if you lose your log book.
• Data must not be entered in a disorderly form; documentation must be timely, chronological, and clear.
• Figures must be exact and should not be rounded up.
• Don’t forget to keep a spare log and back up the one you have if you use a spreadsheet (the last thing you want is to lose your data).
• Consult with HMRC if you are not sure about some of the rules.

For more information about mileage allowance and reimbursements check out our HMRC mileage guide.

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