Why the company car mileage cost calculator matters
Reimbursement rates are averages across the whole vehicle fleet in the country, so for any specific car they are either generous or a quiet loss. This page turns that decision into a handful of inputs you can defend in a budget review: volume, unit cost, rate of adoption, and time. The output is a planning baseline, not a promise — it tells you whether the idea deserves a vendor quote, a pilot, or a pass.
- • Biggest swing factor: fixed cost per month
- • Second-order factor: miles driven, which spreads the fixed cost
- • Often ignored: the reimbursement rate
What actually changes the answer
fixed cost per month moves this number first, then miles driven, which spreads the fixed cost. Run a conservative case and an upside case before you commit. If the maths only works in the upside case, treat it as a time-boxed test with a kill date rather than a line in next year's plan.
What to do with the result
If your all-in cost per mile is below the reimbursement rate, high mileage is profitable. If it is above, negotiate a car allowance instead.
Related guides
Long-form playbooks on the same topic, written by the RevenueLab editorial team.
FAQ
What does the company car mileage cost calculator work out?
It applies Cost per mile = (fixed costs + miles × variable cost) ÷ miles; Profit = miles × rate − total cost to the values you enter for miles driven per month, fixed costs per month, variable cost per mile, mileage reimbursement rate you receive. Reimbursement rates are averages across the whole vehicle fleet in the country, so for any specific car they are either generous or a quiet loss.
How accurate is this company car mileage cost calculator?
Depends on honest fixed costs including depreciation. Excluding depreciation flatters the result significantly. Replace the defaults with your own invoice, usage export, payroll data, statement, or vendor quote before making a commitment — the maths is exact, so the answer is only as good as the inputs you feed it.
Which input should I stress-test first?
fixed cost per month. Re-run with a pessimistic value for it; if the decision flips, that assumption is the thing you need real data on before signing anything. After that, check miles driven, which spreads the fixed cost and the reimbursement rate.
Which scenario should I start from?
Start with the preset closest to your situation — low utilisation, typical month, high utilisation — then edit the sliders. Presets are realistic starting points, not benchmarks to match, and every change updates the result instantly.
What should I do after running the numbers?
If your all-in cost per mile is below the reimbursement rate, high mileage is profitable. If it is above, negotiate a car allowance instead. A useful planning benchmark to compare against: The IRS standard business mileage rate sits near 67 cents.
Can I share or save this calculation?
Yes. Your inputs are written into the page URL, so copying the link shares the exact scenario you are looking at — the person who opens it sees the same numbers. You can also export the inputs and results to CSV or PDF from the result card and keep it with the rest of your workings.
How this calculator is built
Independently maintained
Written by Sam Doshi and the RevenueLab editorial team. We don't sell the data feeds this tool is built on.
Sourced from primary data
Benchmarks come from public AdSense / Stripe / IRS disclosures and reader-submitted data — never third-party "$X per view" claims. Full methodology.
Last editorial review
Reviewed on a rolling quarterly cycle. Dated reviews are published on the methodology record for each calculator.
Editorial standards
See our editorial policy and disclaimer. Results are estimates, not advice.