How Do You Calculate Cost Per Mile (CPM) for a Semi Truck?

By Erkan Ozturk — owner-operator, HAWD Trucking LLC (USDOT 4436030), Chattanooga TN · Last updated July 10, 2026

What is cost per mile, and why are there two versions of it?

Cost per mile answers the only question that matters before you commit a truck to a lane: what does one mile actually cost me to run? Driver to driver, the confusion usually starts because there are two honest versions of the number, and they do different jobs.

The first is the per-load CPM — backward-looking, specific to one load. You add up everything that load costs (fuel, fixed and variable cost for every mile driven, percentage fees, tolls, lumper) and divide by the load's loaded miles:

CPM = totalExpenses ÷ loadedMiles

The denominator is loaded miles, not total miles. Deadhead miles burn the same diesel and wear the same tires, so they belong fully in the numerator as a cost — but they earn nothing, so they never get to dilute the denominator. Priced this way, deadhead can't hide inside a flattering average.

The second is your base CPM — forward-looking, built once from your cost profile and updated when your costs change. It is the number this guide teaches you to build, and it has exactly three parts:

baseCPM = fixedCPM (weeklyFixed ÷ weeklyMileGoal) + variableCPM + fuelCPM (price ÷ MPG)

Fixed costs arrive whether you turn a mile or not. Variable costs accrue with every mile. Fuel is variable too, but it moves weekly with the diesel market, so it earns its own component. Your real cost per mile is the sum of the three — one honest number, and everything downstream (break-even, target rate, whether a load leaves anything in your pocket) is built on it.

Which costs does a semi truck actually carry?

Most cost-per-mile numbers come out too low for one reason: items got left off the list. The inventory below is the full owner-operator cost stack. Every line is real money leaving your business, including the one drivers skip most often — your own salary. If your paycheck isn't a cost line, your CPM describes a business that works only when you work for free.

Two classification calls deserve a word. Depreciation belongs in the variable column even on a paid-off truck: every mile consumes a slice of the machine's remaining life, and the reserve is what lets you replace it without starting over. And the tax-and-permit pile splits — HVUT, IRP, and UCR are flat annual costs (fixed), while NY HUT, KYU, NM WDT, and Oregon's weight-mile tax bill you by the mile (variable).

How do you convert monthly costs to weekly — and why not divide by 4?

Fixed CPM is a weekly calculation, but most fixed bills arrive monthly. Here is the detail most spreadsheets get wrong: a month is not 4 weeks. A year has 52 weeks and 12 months, so one month averages 52 ÷ 12 ≈ 4.333 weeks. The exact conversion is:

weeklyCost = monthlyCost × 12 ÷ 52   (a month averages ≈ 4.333 weeks, not 4)

Divide a monthly bill by 4 and you are pretending the month is shorter than it is, so each week absorbs too much of the bill — every converted cost comes out 8.33 percent too high. Run that shortcut for a full year and you've booked 13 monthly payments into a 12-payment calendar.

The error always points the same way: an inflated weekly figure means an inflated fixed CPM, which means an inflated break-even rate. That sounds harmlessly cautious until you realize your whole pricing floor is built on a number that's 8 percent fiction. The math in this guide — and every table below — uses exact 52/12.

How do you calculate fixed cost per mile?

fixedCPM = weeklyFixed ÷ weeklyMileGoal

Add every fixed line from the inventory, converted to weekly, and divide by the miles you realistically run in a week. The denominator matters as much as the numerator. Fixed costs don't shrink when the truck sits, so fewer miles means each mile carries a bigger slice: $2,500 of weekly fixed costs spread over 2,500 miles is $1.00 per mile — over 2,000 miles it's $1.25, and over 1,800 miles it's $1.39.

Be honest with the mile goal. ATBS reported that the average owner-operator ran roughly 95,000 miles in its 2025 performance data — about 1,800 miles a week across a full year, once home time, breakdowns, and slow weeks are averaged in. If you set the goal at 3,000 because it's a nice round number, your fixed CPM will look better than your business actually is, and the gap surfaces later as money that never arrives.

What goes into variable cost per mile?

Variable CPM covers the costs that accrue with each mile but get paid in lumps: maintenance, tires, depreciation, and mileage-based taxes. Because the bills arrive irregularly — a $2,400 brake job here, a set of drives there — the workable method is a per-mile reserve: an amount you set aside every mile so the money exists when the lump lands.

A reserve build-up might look like this: maintenance $0.15 per mile, tires $0.04, depreciation reserve $0.10, mileage taxes $0.03 — a variable CPM of $0.32. Your figures will differ with the age of your truck and the states you run; the structure is what carries over. If you've owned the truck a year or more, the most honest source is your own records: total spent on each category, divided by total miles driven over the same period.

How do you calculate fuel cost per mile?

fuelCPM = dieselPrice ÷ MPG

Fuel is usually the biggest single per-mile cost you carry, and it's the one that moves weekly. As of the EIA weekly U.S. on-highway diesel average of $4.578 per gallon (published July 6, 2026), a truck getting 7.5 MPG carries $4.578 ÷ 7.5 = $0.61 per mile in fuel. Efficiency moves that number fast: at NACFE's reported fleet average of 7.77 MPG (2023 Fleet Fuel Study) it's $0.59, and at the roughly 6.9 MPG NACFE cites as the national average it's $0.66 — a seven-cent-per-mile spread on the same gallon price.

Use your truck's measured MPG, not the brochure's. And when you price a specific load rather than your baseline, remember fuel is burned on every mile, empty or loaded:

fuelCost = (totalMiles ÷ MPG) × dieselPrice   ← includes deadhead miles

The full treatment — where the EIA index comes from, how deadhead changes the math, and worked examples at different MPGs — is in How do you calculate fuel cost per mile for a truck?

What does a full base CPM build-up look like?

Here is the whole calculation assembled with round example numbers. First, the weekly fixed side — every bill converted with exact 52/12 and rounded to whole dollars:

Then the three components, summed:

This example truck costs $1.93 per mile to run — before anyone takes a percentage of the gross. If a dispatcher and factoring company together take 6 percent, the true floor rate becomes $1.93 ÷ (1 − 0.06) = $2.05 per loaded mile, because percentage fees gross the floor up rather than adding to it. That divide-don't-add step is its own guide: How do you calculate your break-even rate per mile?

How does your number compare to published averages?

For calibration, not for copying: ATRI's operational-cost study — the most-cited figure in the industry — puts the average total marginal cost of trucking at $2.260 per mile for 2024 (published July 2025). On the income side, ATBS reported an average owner-operator net income of $71,800 on roughly 95,000 miles in 2025 — about $0.76 of net income per mile — with the top third of its clients averaging around $166,000.

The spread between the average and the top third is the whole argument for doing this math yourself. An average blends new trucks with paid-off ones, $1,200-a-month insurance with $2,400, drivers running 2,800 miles a week with drivers running 1,500. Your base CPM is none of those blends — it's your equipment, your bills, your lanes. Don't be the average driver. What counts as a strong rate against your number is covered in What is a good rate per mile for owner-operators?

What do you do with a base CPM once you have it?

You hold it up against loads. A real snapshot from July 10, 2026: Erie, PA to Buffalo, NY to Boston, MA — $1,350 rate, 458 loaded miles plus 93 deadhead, $210 in tolls, 7.5 MPG at the EIA diesel average of $4.578/gal, 3 percent dispatch plus 3 percent factoring, $0.96 combined fixed-and-variable operating cost per mile. Total expenses come to about $1,156 — fuel $336, operating cost $529, fees $81, tolls $210. Per-load CPM: $1,156 ÷ 458 loaded miles = $2.52. The rate per loaded mile is $1,350 ÷ 458 = $2.95. The load clears its cost by about $194 — an estimated $15.50 per hour over an estimated 12.5-hour shift, where napkin math (rate minus fuel minus tolls) had promised +$804 and roughly $64 an hour. Same load, $610 apart; only one of the two numbers knew the truck's cost per mile.

Building the base CPM by hand takes an evening with your bills and this page. LoadWizz's Cost Profile Wizard walks this full stack in 13 steps on mobile and builds your personal base CPM with exact 52/12 period math — your cost DNA, not an industry average. Either way, the sequence is the same: cost per mile first, then the break-even rate it implies, then the load math. The full chain, end to end, is in How do you calculate whether a load is actually profitable? — and the rest of the plain-math series lives at the Learn hub.