Vehicle Mileage Log for Schedule C: What the IRS Actually Asks For (Free Worksheet)

If you drive for your business — meeting clients, picking up supplies, making deliveries — your vehicle expenses can be a meaningful deduction on Schedule C. But before your accountant can calculate anything, the IRS wants specific information about how the vehicle was used, not just a total dollar figure.

This guide walks through exactly what Schedule C, Part IV asks for, the two ways to calculate your deduction, and gives you a free worksheet to fill in before tax time.

Two ways to deduct vehicle expenses

Self-employed taxpayers can generally choose between two methods:

Standard mileage rate. You track your business miles and multiply by the IRS's standard rate. The IRS set the 2026 business rate at 72.5 cents per mile in December 2025 — but then revised it mid-year: for business miles driven July 1 through December 31, 2026, the rate is 76 cents per mile, up from 72.5 cents for miles driven January 1 through June 30, 2026. The IRS made this change to reflect rising fuel prices; it's uncommon but not unprecedented (a similar mid-year change happened in 2022).

That means a 2026 mileage deduction is really two calculations, not one: multiply your business miles driven in the first half of the year by 72.5 cents, multiply your business miles driven in the second half by 76 cents, and add the two results together. Keeping a log that notes the date of each trip — which Part IV already expects of you — is what makes this split possible; a single year-end mileage total isn't enough to apply two different rates.

If you use this method for a vehicle you own, you must choose it in the first year the vehicle is available for business use — after that, you can switch between standard mileage and actual expenses in later years. If you lease the vehicle, you must use the standard mileage rate for the entire lease term if you choose it at all.

Actual expense method. You track and deduct your actual costs — gas, insurance, repairs, depreciation, and more — prorated by the percentage of miles driven for business.

Either way, the IRS wants supporting information about your vehicle's use, which brings us to Part IV.

What Schedule C, Part IV actually asks

If you're claiming car or truck expenses and aren't required to file Form 4562 for this business, you complete Part IV of Schedule C — "Information on Your Vehicle." It's a short section, but every line matters:

• Line 43: When did you place your vehicle in service for business purposes?
• Line 44: Of the total miles you drove during the year, how many were for (a) business, (b) commuting, and (c) other purposes?
• Line 45: Was your vehicle available for personal use during off-duty hours?
• Line 46: Do you (or your spouse) have another vehicle available for personal use?
• Line 47a: Do you have evidence to support your deduction?
• Line 47b: If yes, is that evidence written?

Notice that lines 45–47 aren't about money at all — they're about whether your mileage claim is credible and documented. A written mileage log carries far more weight with the IRS than an estimate reconstructed after the fact.

If you used more than one vehicle for business during the year, the IRS wants this information reported separately for each additional vehicle.

What to gather before your appointment

• Vehicle year, make, and model
• Date the vehicle was placed in service for business
• Total miles driven during the year, broken into business, commuting, and other
• Whether the vehicle was available for personal use during off-duty hours
• Whether you or your spouse have another vehicle available for personal use
• Whether you have written evidence (a mileage log, app export, or logbook) supporting your business miles

If you're using the actual expense method instead of standard mileage, also gather your annual totals for gas, insurance, repairs and maintenance, and lease or loan payments.

Common mistakes to avoid

• Estimating mileage at year-end instead of logging it. The IRS specifically asks whether your evidence is written — an after-the-fact estimate isn't the same as a logbook.
• Switching methods incorrectly. If you leased the vehicle and want standard mileage, you're locked into that method for the full lease term.
• Forgetting commuting miles. Miles driven from home to a regular place of business are commuting miles, not business miles, even if you're self-employed.
• Not separating multiple vehicles. Each vehicle used for business needs its own set of answers.

Get organized in one page

Our free U.S. Motor Vehicle Information Sheet mirrors Schedule C, Part IV line for line, so nothing gets missed. Fill it in on your computer or print it and write by hand, then hand it to your accountant or tax preparer.

Frequently asked questions

Why are there two standard mileage rates for 2026?

The IRS set the 2026 business rate at 72.5 cents per mile in December 2025, then revised it mid-year due to rising fuel prices. Miles driven January 1 through June 30, 2026 use 72.5 cents per mile; miles driven July 1 through December 31, 2026 use 76 cents per mile. You calculate each half of the year separately, then add the two amounts together.

Can I deduct commuting miles?

No. Commuting from home to your main place of business is considered personal, not business, mileage — even for the self-employed.

Do I need a mileage app, or is a paper log enough?

Either works, as long as it's a contemporaneous record — created at or near the time of each trip — rather than reconstructed later. The IRS specifically asks whether your evidence is written.

What if I use my vehicle for more than one business?

You'll generally need to allocate mileage between each business and keep records supporting the split.

Can I switch from standard mileage to actual expenses next year?

If you owned the vehicle and used standard mileage in the first year it was available for business, you can switch to actual expenses in a later year. Leased vehicles don't have this flexibility — the method choice applies for the whole lease term.

How Heightly fits in

Heightly is built for unincorporated sole proprietors in the U.S. and Canada who want their bank and credit card statements organized into a Tax Prep Report — without paying for a full bookkeeping subscription. Upload your statements, and Heightly categorizes your transactions and aligns them to IRS Schedule C or CRA Form T2125, flagging anything that needs your input along the way.

Heightly can identify gas, insurance, and repair payments from your statements — but it can't see your odometer. The worksheet above fills that gap, so your finished report is that much more complete when it reaches your accountant.

See how Heightly works or try a free preview with your own statements.