Where Does Mileage Go on Schedule C: Line 9 and Part IV

On Schedule C, business mileage shows up in two places. The dollar value of your vehicle deduction goes on Line 9, labeled “Car and truck expenses.” The mile counts that support that dollar figure—your business, commuting, and personal miles—go in Part IV of the same form. You never write a raw mileage number on Line 9 itself; Line 9 is always a dollar amount.

Turning Miles Into the Line 9 Dollar Amount

There are two ways to calculate what goes on Line 9, and you pick one.

Standard Mileage Rate

Multiply your business miles for the year by the IRS rate. For 2026, that rate is 72.5 cents per mile.¹ Ten thousand business miles produces a $7,250 deduction. Add any business parking fees and tolls to that total before entering it on Line 9.² Do not also add gas, insurance, repairs, depreciation, or lease payments. The per-mile rate already covers those.

Actual Expenses

Add up your vehicle operating costs for the year—fuel, oil, repairs, tires, auto insurance, registration—then multiply the total by your business-use percentage.² If your vehicle costs were $8,000 and 75 percent of your miles were business, you enter $6,000 on Line 9.

What Goes in Part IV

Part IV is where the mileage numbers themselves live. Complete it if you are using the standard mileage rate, leasing your vehicle, or claiming expenses for a fully depreciated vehicle—and you are not otherwise required to file Form 4562.³ The section asks for:

Line 43: the date you started using the vehicle for business.
Line 44a–c: your total miles broken into business, commuting, and personal.
Line 45: whether the vehicle was available for personal use off duty.
Line 46: whether you or your spouse had another vehicle for personal use.
Line 47a–b: whether you have evidence supporting the deduction, and whether it is written.

The business-mile figure on Line 44a is the same number you multiplied by the standard rate (or used to calculate your business-use percentage) to arrive at Line 9.⁴ If you must file Form 4562—for instance, because you are claiming depreciation on the vehicle for the first time—the vehicle information goes in Part V of that form instead of Part IV of Schedule C.

Vehicle Costs That Belong on Other Lines

Line 9 is not a catchall for everything vehicle-related. When you use the actual expense method, several costs get their own lines:

Depreciation goes on Line 13, not Line 9.⁵
Lease payments go on Line 20a.
Vehicle loan interest (business portion) goes on Line 16a or 16b.²
Personal property taxes on the vehicle go on Line 23.

Business parking and tolls are the exception. Those can be added into the Line 9 total under either method.² Parking at your regular workplace is a commuting cost and is not deductible anywhere.

Which Miles Count as Business Miles

The number you put on Line 44a and use to build Line 9 has to be actual business miles, not every mile you drove for anything related to work.

Commuting Does Not Count

Driving from home to your regular workplace and back is commuting, no matter the distance. The IRS treats it as personal. Taking business calls on the drive or carpooling with a coworker does not convert it into business travel.⁶

What Does Count

Miles between two work locations on the same day are deductible, as are trips from your regular workplace to a client or customer site. Trips to a temporary work location outside your metropolitan area also count, provided the assignment is realistically expected to last one year or less.⁶

The Home Office Situation

If your home qualifies as your principal place of business, trips from your home office to any other work location in the same business are business miles, not commuting.⁶ The home office has to meet the requirements in Publication 587 for this to apply.

Mileage That Does Not Go on Schedule C at All

Schedule C is only for self-employment mileage. Charitable driving is deducted on Schedule A at 14 cents per mile.⁷ Medical mileage is claimed on Schedule A under medical expenses at 21 cents per mile for 2025. Neither belongs on Line 9 or in Part IV, and combining them with business miles can invite questions during an audit.

Records Behind the Numbers

Whatever you put on Line 9 and in Part IV has to be backed by contemporaneous records showing the amount of each expense, the date and location of each trip, and its business purpose.⁸ A mileage log, on paper or in an app, is the usual way to do this, and it should separate business miles from commuting and personal miles trip by trip. If you use actual expenses, keep receipts for fuel, repairs, insurance, and every other cost you claim. Without adequate documentation, the IRS can disallow the entire deduction during an audit.

1
Internal Revenue Service. 2026 Standard Mileage Rates (Notice 2026-10)
2
Internal Revenue Service. Instructions for Schedule C (Form 1040) (2025)
3
Internal Revenue Service. Instructions for Form 4562 (2025)
4
Internal Revenue Service. 2025 Schedule C (Form 1040) Profit or Loss From Business
5
Internal Revenue Service. 2025 Instructions for Schedule C (Form 1040)
6
Internal Revenue Service. Publication 463 (2024), Travel, Gift, and Car Expenses
7
Internal Revenue Service. Publication 526 (2025), Charitable Contributions
8
Office of the Law Revision Counsel. 26 USC 274 – Disallowance of Certain Entertainment, Etc., Expenses