How to Calculate Maintenance Cost Per Mile for Your Fleet

Why Cost Per Mile Matters

If you don't know your maintenance cost per mile (CPM), you don't know whether your rates are covering your real expenses. Many small fleet owners set their rates based on fuel costs and driver pay but underestimate maintenance — which can represent 10–15% of total operating costs.

According to the American Transportation Research Institute (ATRI), the industry-wide average for repair and maintenance is $0.198 per mile as of 2024, representing approximately 9% of the total $2.26 per mile operating cost for a Class 8 truck. The annual R&M cost per truck averages $16,192. Well-maintained fleets benchmark at $0.12–$0.18 per mile, while fleets with deferred maintenance can exceed $0.25 per mile.

How to Calculate It

The formula is simple:

Maintenance CPM = Total Maintenance Spend ÷ Total Miles Driven

Total Maintenance Spend includes parts, labor (including your own time if you value it), tow costs, shop invoices, and any maintenance-related downtime costs you can quantify.

For example, if your 10-truck fleet spent $18,000 on maintenance last quarter and drove 300,000 miles, your CPM is $0.06 per truck — below average and a sign your PM program is working. If the same fleet spent $45,000, your CPM is $0.15 — normal range but worth investigating.

What Drives Maintenance Costs Up

• Aging vehicles: Trucks over 500,000 miles have significantly higher maintenance costs
• Missed preventive maintenance: Reactive repairs cost 3–5x more than preventive service
• Poor parts sourcing: Overpaying or using incorrect specifications
• Shop markup: External shops charge labor rates that in-house maintenance avoids
• Downtime costs: A truck that's not moving isn't earning

How to Reduce Your CPM

The single most effective way to reduce maintenance CPM is a disciplined preventive maintenance program. Beyond that, consider tracking parts costs by vendor to identify savings, building relationships with 2–3 local shops and comparing rates, investing in driver training on pre-trip inspections, and tracking CPM by individual unit to identify trucks costing more than they earn.

Track It Automatically

Calculating CPM manually requires pulling data from invoices, shop receipts, and mileage logs — which is why most small fleet owners don't do it regularly. Truck Genie tracks work order costs, parts, and labor for every unit, making it possible to see your maintenance CPM without the spreadsheet gymnastics.

Sources: American Transportation Research Institute (ATRI) 2025 Operational Costs of Trucking Report; Fleet Equipment Magazine; Fleet Maintenance Magazine ATRI analysis (2025).