You drove 120 miles to a client site last week. Who pays for that gas, the wear on your tires, and the two hours behind the wheel? If the answer is “you,” you are leaving money on the table. And if the answer is “the client,” you need to know exactly how to document it and put it on an invoice without undercharging yourself or triggering a tax headache.

Billing clients for mileage is one of the most common questions freelancers and contractors ask, and it gets confusing fast because two completely different sets of rules are in play at the same time: what the IRS lets you deduct, and what your client has agreed to pay you. They are not the same thing. Let’s untangle them.

Client Reimbursement and the IRS Deduction Are Two Separate Things

This is the single most important concept in this article, so read it twice.

When you deduct business mileage on your taxes, you use the IRS standard mileage rate, which is $0.725 per mile for 2026. That deduction lowers your taxable income on Schedule C.

When a client reimburses you for mileage, that is a billing arrangement between you and them. The client can agree to pay you the IRS rate, a flat fee, a different per-mile rate, or nothing at all. The IRS does not set what your client owes you. Your contract does.

Here is where people get tripped up: any mileage reimbursement a client pays you is taxable income to you. If your client sends you a 1099 at the end of the year, that reimbursement is almost always included in the total. So you report it as income, and then you deduct your actual business miles at $0.725 to offset it.

That means the smartest move is usually to bill the client at the IRS rate. If they reimburse you $0.725 per mile and you deduct $0.725 per mile, the reimbursement income and the mileage deduction cancel out. You come out even, and you were paid for the real cost of driving.

Decide How You’ll Charge Before the Work Starts

Do not wait until after the trip to figure out how mileage gets billed. Nail it down in your freelance contract or project agreement before you drive anywhere.

You have three common options:

Bill at the IRS standard rate ($0.725/mile for 2026). This is the cleanest and easiest to defend. Clients recognize the number, it is tied to a published federal rate, and it covers gas, maintenance, insurance, and depreciation in one figure. For a 120-mile round trip, you bill $87.

Charge a flat travel fee. Some freelancers prefer “$75 per on-site visit” or “$150 for any trip over 50 miles.” This is simpler to quote and great when trips are predictable. The downside: if a trip runs long, you absorb the extra cost. Flat fees also do not automatically match your IRS deduction, so keep tracking your real miles regardless.

Build travel into your rate. If you only occasionally travel, you might just set your rate high enough to cover it and never itemize mileage at all. The risk is that a surprise 300-mile week eats your margin. Only do this if travel is rare and short.

Whatever you pick, put it in writing. Specify the rate, what counts as billable travel, and whether tolls and parking are reimbursed on top of mileage (they usually should be, since the standard mileage rate does not include tolls or parking).

Know Which Miles You Can Actually Bill

Not every mile you drive for a project is billable or deductible. The IRS draws a hard line between a commute and business mileage, and you should draw the same line with clients.

Driving from your home to a regular workplace is a commute, and commuting is never deductible. But if you drive from your home office to a client’s site, from one client to another, or to pick up project supplies, those are business miles.

Be honest about this when you bill. Charging a client for your morning commute is both bad practice and impossible to back up if the mileage ever shows up in an audit. Bill the miles that are genuinely tied to serving that client.

Document Every Mile Like the IRS Is Watching

Because your client reimbursement becomes taxable income, and because you will deduct those same miles, your mileage log has to hold up. The IRS mileage log requirements are specific. For each trip you need:

• The date of the trip
• The starting point and destination
• The business purpose (which client, what for)
• The miles driven

A log that just says “drove around for work, 400 miles” will not survive an audit. “March 14, home office to Acme Corp, Dayton, client kickoff meeting, 60 miles each way, 120 total” will.

The good news is this same log does triple duty. It supports your client invoice, it backs up your Schedule C mileage deduction, and it protects you if the client questions the charge. Tracking your mileage with real timestamps and odometer readings is non-negotiable if you want to bill for it.

Put Mileage on the Invoice the Right Way

When you bill a client for travel, make it a clear, separate line item on your invoice. Do not bury it inside your service fee.

A clean mileage line looks like this:

Mileage reimbursement: 240 miles @ $0.725 = $174.00

If you have multiple trips in a billing period, you can list them separately or summarize with a total mile count. Attach or reference your mileage log if the client wants backup. List tolls and parking as their own line items with receipts, since those are extra on top of the per-mile rate.

Keep your travel charges on the same payment terms as the rest of your work. If you bill Net 15 or Net 30, mileage follows the same schedule. And if the client drags their feet, your travel costs are covered by the same process you’d use when a client won’t pay an invoice.

The Tax Side: Report It, Then Deduct It

At tax time, handle mileage in two steps.

First, the reimbursement you collected is income. It likely shows up on any 1099 your client issues, and it belongs in your gross receipts on Schedule C. Do not try to exclude it just because it was “only” a reimbursement. To the IRS, money a client pays you is income.

Second, you deduct your business miles. You can use the standard mileage rate at $0.725, or you can run the numbers on the actual expense method if your real costs (gas, insurance, repairs, depreciation) are high. Most freelancers find the standard rate wins on simplicity and often on dollars, but it is worth comparing if you drive a lot or own an expensive vehicle.

When you bill at the IRS rate and deduct at the IRS rate, the two net to roughly zero and you are not taxed on the reimbursement. This also matters for your quarterly estimated taxes: the reimbursement income raises your estimated payment, but the matching deduction brings it back down, so don’t panic when the reimbursement lands in your account.

One more note: the mileage deduction reduces both your income tax and your self-employment tax, since Schedule C profit is what self-employment tax is calculated on. Every mile you log and deduct saves you real money twice.

A Quick Example From Start to Finish

Say you are a consultant who drives 300 business miles serving one client over a month.

You bill them 300 miles at $0.725 = $217.50, listed as its own invoice line. The client pays it, and at year end includes it in your 1099. You report $217.50 as income on Schedule C, then deduct 300 miles x $0.725 = $217.50. Net tax impact on the mileage: zero. You were fully paid for the drive, and the IRS took nothing extra.

That is the whole system working as intended. Bill clearly, log carefully, report honestly, deduct correctly.

numlr tracks your business mileage with GPS and turns it straight into an IRS-ready log and a billable invoice line so you get reimbursed by clients and deduct every mile without doing the math twice. Try numlr free.