How to calculate fleet maintenance cost per kilometre (and per mile)

The calculation in kilometres

Work it out for one unit at a time, then for the fleet as a whole.

The top line is all the maintenance spending the unit consumed, whoever did the work: parts and fluids, the hours your own technicians spent on it, invoices from dealers and outside shops, and tires. The bottom line is the closing odometer reading minus the opening one. If the unit started the year at 412,300 km and ended it at 588,300 km, it travelled 176,000 km.

For a fleet figure, add up the spending of every unit and divide by the kilometres of every unit. Resist averaging the per-unit results. A spare tractor that ran only a few thousand kilometres can carry a very high per-kilometre figure, and a plain average gives that one unit as much say as a truck that ran ten times as far. The example further down shows how far apart the two answers can drift.

Choose the window with care. Monthly numbers jump around too much to read: a turbocharger in March makes March look alarming and April look cheap. Most fleets work from a rolling twelve months, refreshed every quarter, and keep a calendar-year figure for the budget.

Kilometres and miles: converting without mixing them up

Plenty of Canadian fleets live in both units. US-built trucks may arrive with odometers set to miles, customers on US-bound lanes quote rates per mile, and many shop and industry reports are written per mile. The arithmetic is simple; the mistakes come from mixing units inside one total.

• Cost per km to cost per mile: multiply by 1.609. A unit at 0.15 per km costs about 0.24 per mile.
• Cost per mile to cost per km: divide by 1.609. A quote of 0.30 per mile is about 0.19 per km.
• Distances: divide kilometres by 1.609 to get miles, or multiply miles by 1.609 to get kilometres.

Before you add up a fleet total, put every unit’s distance into one unit. A tractor whose odometer reads in miles and one that reads in kilometres cannot share a column until one of them is converted, and a fleet figure built from both will be wrong without looking wrong.

What belongs in the cost, and what stays out

The number should describe the cost of keeping a unit in safe running order as it wears. Count what the unit consumed in maintenance and leave out spending that has another cause.

Write your rules down once and apply them every period. If the figure moves because the definition moved, the trend means nothing.

The records already hold most of it

Canadian carriers keep the raw material anyway. National Safety Code Standard 11 asks for a vehicle file that shows the date and nature of every repair and maintenance job, the parts replaced and the invoices, and the odometer reading at every servicing or repair. In Ontario, section 16 of Regulation 199/07 lists the same kind of record and adds the outside shop’s invoice, the invoice or receipt for each part used, and the odometer reading at the end of each job. When every work order and invoice carries a unit number, the cost side is a sum. Our guide to truck maintenance records covers how to keep that file.

For distance, read the odometer. Every kilometre wears the truck, including empty running and the trip to the shop, so dispatched or paid kilometres understate the real figure. ELD reports, trip sheets and fuel tax distance records usually hold readings close to the start and end of each period.

Worked example: three tractors over one year, in kilometres

A carrier runs three highway tractors bought in different years. The figures are in your own currency, and shop labour is charged at a loaded rate of 95.00 an hour.

Unit 21 costs about 0.07 per kilometre to keep running, Unit 22 about 0.13 and Unit 23 about 0.28. The fleet figure is 81,000.00 over 533,000 km, or 0.152 per kilometre. Averaging the three unit figures instead would give 0.160, too high, because the costliest tractor also travelled the least.

The detail matters as much as the total. Unit 23’s outside repair bills are more than nine times Unit 21’s, which usually points to breakdowns far from home: tows, road calls and repairs at whatever shop could take the truck. That pattern is a reliability problem before it is a cost problem.

Expressed in miles, the fleet’s 533,000 km is about 331,200 miles and its cost is about 0.245 per mile, the figure to use if you are comparing with a per-mile quote.

Per unit or per kilometre: which number answers which question

The two figures look similar on a report but answer different questions.

• Spending per unit is the total maintenance cost of one truck or trailer over the period. It suits budgets, and comparisons between units that run similar distances. Unit 23 cost 43,000.00 to maintain, about three times Unit 21.
• Cost per kilometre divides that total by the distance travelled. It suits comparisons between units that run very different distances, and pricing the maintenance share of a lane. Per kilometre, Unit 23 is close to four times as expensive as Unit 21, because it cost more and ran less.

Be careful with units that sit part of the year, such as a spare tractor or a seasonal trailer. The periodic inspection, the yearly registration and calendar-based PM cost the same whether the unit runs 40,000 km or 200,000 km, so a quiet unit can look expensive per kilometre without anything being wrong with it. Compare units of similar age, model and work, and expect winter-heavy routes on salted roads to cost more than summer highway work.

Trailers rarely have odometers. Most fleets compare them by spending per unit per year, or use a hubodometer reading where one is fitted.

Benchmarks: what is published, and for which country

The figure most often quoted comes from the American Transportation Research Institute (ATRI), a US not-for-profit research organization for the trucking industry Its Analysis of the Operational Costs of Trucking: 2026 Update, released on July 15, 2026, put the industry-average cost to operate a truck in 2025 at 2.336 per mile, 3.4 percent above the year before and the highest in the report’s history. Without fuel, the figure was 1.854 per mile. Repair and maintenance rose 8.6 percent and tires 6.4 percent; of all line items, only tolls rose faster than repair and maintenance.

Read those numbers as American figures: per mile, in US currency, and covering the whole cost of operating a truck rather than maintenance alone. Converted to distance in kilometres, 2.336 per mile is about 1.45 per kilometre, still in US currency, so it cannot be set beside a Canadian fleet’s costs in Canadian currency without a currency conversion on top. ATRI offers the full report as a free download after a short form.

None of the Canadian regulators this guide relies on publishes an equivalent per-kilometre maintenance figure. That is less of a gap than it sounds. Industry averages mix fleets of every size, sector, age and accounting method, and they rarely count shop labour the way you do. Your own units, compared with each other quarter after quarter, tell you more.

Keep, rebuild or replace: using the trend

Maintenance cost per kilometre climbs as a unit ages, and at some point keeping it costs more than replacing it. The trend tells you when to sit down and do the comparison.

1. Refresh each unit every quarter on a rolling twelve months, so a rising line shows up before the big invoice does.
2. Set it against its peers: the same model and age band, doing similar work. A unit well above the group deserves a closer look.
3. Forecast the coming year: an in-frame overhaul, aftertreatment parts, a clutch, a set of drive tires, the repairs the next periodic inspection is likely to demand. Divide by the kilometres you expect it to run.
4. Price the downtime. Count the days the unit spent out of service and what they cost in missed loads, rentals or overtime.
5. Weigh the alternative. Set the old unit’s forecast maintenance and downtime against a newer unit’s lower maintenance and higher cost of ownership.

In the example, the shop expects Unit 23 to need about 52,000.00 of work next year over 150,000 km, roughly 0.347 per kilometre. Unit 21 runs at about 0.073, so over the same distance the maintenance gap is about 41,100.00, before the 26 days Unit 23 spent out of service last year. If the gap plus the lost days is larger than the extra yearly cost of owning a newer tractor, replacement wins.

Maintenance is one line in that decision. Fuel, driver pay, insurance and financing all change with a newer unit, which is why many carriers look at the whole picture in TruckerPro’s truck fleet management software.