Guide to IRS mileage log requirements

Business travel can be a significant expense, whether you run a large company, a small business, or you’re self-employed. Fortunately, you can claim the bulk of these travel costs on your taxes so long as the expenses are strictly business-related trips.

If you use a personal vehicle, however, the IRS requires more than just a receipt: You’ll need a detailed mileage log for taxes. We break down why mileage tracking matters, IRS mileage log requirements, and how to create a compliant log.

Why should businesses track mileage?

Let’s say you need to visit a customer or supplier. Or maybe you’re picking up business supplies, moving equipment, or attending a meeting. If you use your personal vehicle for any of these business-related activities, you can deduct the travel costs from your income taxes.

The same applies if you reimburse employees for using their personal vehicles for work purposes. But to claim these valuable deductions, tracking mileage for taxes is essential to maintain accurate and IRS-compliant records.

IRS mileage log requirements

To claim tax deductions for business expenses, the IRS requires you to keep adequate records to prove the accuracy and business necessity of the expenses.

According to IRS Publication 463, this means keeping detailed and timely records that show the date, mileage, address, and purpose of each business trip, as well as odometer readings for the beginning and end of the year. An IRS-compliant mileage log should include:

• Total annual mileage: The total number of miles driven throughout the year for both business and personal use
• Annual business mileage: The total number of miles driven specifically for business purposes during the year
• Per-use business mileage: The number of miles driven for each individual business trip
• Date of use: The specific dates on which the vehicle was used for business travel
• Business destination: The location of each business-related trip (commuting between home and a regular worksite is not deductible)
• Purpose: A brief explanation of the business reason for each trip

Supporting evidence, like emails, meeting invites, or related expense receipts, isn’t required, but it can strengthen your case in the event of an IRS audit.

Should you track personal vs. business mileage separately?

The IRS requires you to separate personal from business mileage. Commuting to and from your regular workplace doesn’t count as business travel, and incorrectly including it could trigger a business tax audit.

To accurately track your mileage, always log the business purpose for each trip, avoid rounding or estimating mileage, and consider using a tracking app that distinguishes personal and business trips.

One common mistake is logging every drive as business-related without clear documentation. Avoid this by being diligent and specific with your entries.

Methods for claiming mileage deductions

The IRS offers two primary methods for calculating mileage expenses: the standard mileage rate and the actual expense method. Choosing the right method can help you maximize your deductions based on your specific situation.

Standard mileage rate method

The standard mileage rate is a fixed dollar amount set annually by the IRS that businesses can deduct from their taxable income for each business mile driven. For the 2025 tax year, the IRS standard mileage rate is 70 cents per business mile.

To claim a deduction using this method, you need to know the total number of business miles driven. For example, if you and your employees drove a total of 15,000 business miles during the year, you would multiply 15,000 by $0.70 to calculate your mileage deduction, which comes out to $10,500.

Actual expense method

The actual expense method requires you to determine the percentage of vehicle use that went toward business versus personal purposes.

To calculate this percentage, you need to know both the total miles driven during the year and the number of miles driven for business. You then divide the business miles by the total miles driven.

For example, if you drove 10,000 miles during the year, and 2,000 of those miles were for business use, your business use percentage is 20%. This allows you to deduct 20% of your total vehicle expenses for the year, including fuel, maintenance, repairs, and depreciation.

What mileage log formats does the IRS accept?

How you record this information and the formats you use are ultimately up to you, but it’s commonly done with a paper log or a mileage tracking app.

Paper mileage log templates

Paper mileage logs, often in the form of a notebook or diary, are the most traditional way to track mileage. You can even buy notebooks specifically designed with mileage log templates that include dedicated fields for all the necessary information.

However, these logbooks only work if you use them consistently for every business trip. When you’re rushing to a meeting or pressed for time, it’s easy to forget to log the required details, which can force you to rely on memory or estimate mileage later.

Digital mileage tracking apps

With smartphones and connected vehicles, mileage logs no longer need to be physical. Many mileage tracking apps are available to log your business miles automatically.

When you start driving, simply note whether the trip is for personal or business use, and the app tracks the mileage for you. You can then add important details like the business purpose afterward. With that said, you still need to remember to activate the app each time you drive, or the trip won’t be recorded.

How long should you keep business mileage records?

The main purpose of a mileage log is to support your claims of business mileage in the event of an IRS audit. You should keep your mileage records for at least as long as your tax return is subject to an audit.

The IRS states an audit can include tax returns filed within the last three years. However, this period can extend up to six years in cases where significant accounting errors are found. Tax experts often recommend retaining business expense records, including mileage logs, for at least seven years.

What to do if you’re audited

If the IRS audits your mileage deductions, it will likely request to see your mileage log. This is where accurate, organized records pay off. To prepare, make sure you:

• Keep digital or paper logs for at least three years (seven to be safe)
• Be ready to show annual odometer readings
• Have supporting materials like calendar appointments, client emails, or expense receipts

If your records are incomplete, you may still be able to reconstruct mileage using appointment logs, navigation history, or fuel receipts, though this is not ideal.

Automate business mileage tracking with Ramp

When you’re rushing from meeting to meeting, it’s easy to forget to log your miles, regardless of whether you use a paper log or an app. Thankfully, you can automate mileage tracking for accurate records.

Ramp’s expense management software simplifies this process with seamless integrations to the apps you already use. When your employees use personal vehicles for business travel, they just need to enter their starting point and destination. Ramp automatically calculates the number of miles driven thanks to a direct integration with Google Maps.

Afterward, employees can add key details like the date and business purpose to keep records IRS-compliant. And with Ramp’s mobile app, employees can scan receipts and submit expenses from the field so you never have to worry about missing documentation.

Try an interactive demo and see why Ramp customers save an average of 5% a year across all spending.