One car, two uses: how the split works
Almost every gig driver uses one car for everything, and that is completely normal. The deduction is for the business portion.
Two numbers make it work:
Business miles, from your log, per trip, with date, destination and purpose.
Total miles for the year, from odometer readings at each end. This is the number almost nobody has, and it is the one that turns a business mileage figure into a proportion rather than an assertion.
Business use percentage = business miles ÷ total miles.
You do not need to log personal trips. Business trips in detail, plus the annual total. Personal is whatever is left.
Why the total matters even under the standard rate: the rate is applied to business miles, and the credibility of that figure comes from it being a plausible share of a known total. A driver claiming 22,000 business miles who cannot say what the car did in total is in a weaker position than one who can, and the difference is two photographs.
Under actual expenses it matters more, because every cost is apportioned by that percentage rather than only informing it.
The two photographs
1 January and 31 December, odometer, with the date visible or the file timestamp intact.
Ten seconds each, twice a year. It is the highest value-per-second action available in this entire subject, and it cannot be done retroactively.
Missed the start of the year? Take one now and note the date. Something is worth considerably more than nothing, and you can reason forward from a mid-year reading with a note explaining it. The end-of-year checklist.
Worked
A full-time delivery driver:
- Odometer 1 Jan: 58,412
- Odometer 31 Dec: 80,140
- Total miles: 21,728
- Business miles from the log: 17,900, split 8,100 in the first half and 9,800 in the second
Business use: 17,900 ÷ 21,728 = 82 percent.
Deduction under the standard rate: (8,100 × $0.725) + (9,800 × $0.76) = $5,872.50 + $7,448 = $13,320.50
Eighty-two percent is high and entirely plausible for someone driving full time. It is defensible precisely because the total is there: the remaining 3,828 miles is the personal driving, and that is a believable amount for a year.
Without the total, the same 17,900 is a number with nothing around it. What happens if the IRS questions your mileage.
Standard rate or actual expenses
Standard rate. Business miles × the rate for the period. The business-use percentage supports the credibility of the mileage figure. Simplest, and right for most gig drivers.
Actual expenses. Total vehicle costs for the year × business-use percentage. Every fuel receipt, service, tyre, insurance premium and registration, plus depreciation. Here the percentage is doing arithmetic rather than supporting a claim, so it has to be right.
The first-year choice for the vehicle constrains what you can switch to later. Decide deliberately in year one. Standard mileage versus actual expenses.
The situations that complicate it
Two drivers, one car. Each deducts their own business miles; the vehicle total covers everyone's driving. Keep separate logs. Two people reconstructing one car's year from memory produces figures that do not reconcile, and the reconciliation is the thing anyone would look at.
Two cars. Track each separately, with its own total. Business use is per vehicle.
Changing cars mid-year. Odometer readings at the changeover for both, plus the usual year-end readings. Fiddly for ten minutes and impossible to reconstruct later.
A leased car. The split works the same way; what differs is how costs are treated under actual expenses and what the lease permits in mileage. Mileage if you lease your car.
The habit
Two photographs a year. A log kept at the time. One export each January.
That is the whole record-keeping requirement for the largest deduction most gig drivers take, and every part of it is cheaper than the alternative. How to start a mileage log today. · What a log has to contain. · What records to keep and for how long.
This page describes the rules, not your situation. Anything unusual belongs with a tax professional.
More in this section
About MileTruth
MileTruth is an iOS app from Baker Ventures LLC that tracks deductible business mileage for gig and delivery drivers and shows true net pay: what is left after mileage, fuel and self-employment tax, not what the platform showed you at acceptance. It is built for people driving several platforms in the same shift, and for anyone who needs a mileage log that would hold up if the IRS asked for it. The app is in development.
Everything on this site is free and needs no account: the mileage deduction calculator, the per-platform pay breakdowns, and the answers, each one linked to the IRS publication or platform document it came from. MileTruth publishes the source for every number, including the 2026 split-year standard mileage rate, because a deduction you cannot substantiate is not a deduction.
Questions and answers
Can you deduct mileage on a car you also use personally?
Yes. Almost every gig driver does, and the deduction is for the business portion. What you need is a record of business miles and the vehicle's total miles for the year, so the business share is a proportion of a known total rather than a figure with nothing behind it.
How do I work out the business-use percentage?
Business miles divided by total miles driven for the year. The business miles come from the log; the total comes from odometer readings at each end of the year, which is the number most drivers do not have.
Do I need to record personal trips?
No. You need business trips in detail and the annual total for the vehicle. Personal miles are whatever is left over, and recording them individually is work with no benefit.
What if my business percentage is very high?
A high share is entirely possible for a full-time driver and it should be supportable. What draws questions is a high percentage with no annual total behind it, because then it is a claim rather than a proportion.
Does the split matter under the standard mileage rate?
Yes. The rate is applied to business miles, and business use as a share of total use is what makes the business mileage figure credible. It matters more under actual expenses, where every cost is apportioned by that percentage.
What if two people drive the same car?
Each person deducts their own business miles, and the vehicle's total covers everyone's driving. Keeping separate logs matters, because two drivers reconstructing one car's year from memory produces figures that do not reconcile.
MileTruth. “One car, two uses: how the split works.” Baker Ventures LLC, September 7, 2026. https://miletruth.bakerventuresstudio.com/answers/one-car-for-business-and-personal-use/