Calculating your cost per mile is something that seems difficult at first but is actually pretty simple, if occasionally tedious. It is something that you should be doing regularly though, because it keeps you informed about how your business is performing, and optimally, it’s probably something you want to track on a month-to-month basis.

To start you will need:
1. All your expense receipts for the month (Including fuel purchases, food, etc.)
2. All of your bills (including insurance, truck payment, health insurance, etc.)
3. Your odometer reading from the beginning and end of the month.

The formula for cost per mile is simply this:

Total Expenses ÷ Total Miles = Cost Per Mile

For Total Expenses, you need to add up all of your expense receipts and bills for the month to get a grand total. If you’re the type that prefers to do this by hand, a spreadsheet can make this easier since it can help you see if you’ve missed something so you don’t have to keep starting over like you might with a calculator. If you prefer an easier method, many trucking software programs will do this for you automatically.

Then you need your Total Miles. This is very simple, subtract your odometer readings:

Odometer from end of month - Odometer from beginning of month = Total Miles

Now you just divide the two numbers to get your cost per mile.

If you have multiple trucks you will want to calculate your CPM for each truck and overall. When you calculate overall, do it like this:

Total Expenses = (Total Expenses for Truck 1 + Total Expenses for Truck 2, etc.)
Total Miles = (Total Miles for Truck 1 + Total Miles for Truck 2, etc.)

Then do the same calculation as before.

For example, let’s say you have just one truck, or are just calculating your CPM for just one of your trucks, and this past month, you’ve spent $3000 in fuel, $150 in tolls, $75 in supplies for the truck, your truck payment is at $1000, $200 for food, $800 for insurance, and $110 for your cell phone. Realistically, we know there will be more expenses than this, but this will get us started. Then you check your odometer readings for the beginning and end of the month: 356,566 at the beginning, and 358,432 at the end.

$3000 + $150 +$75 + $1000 + $200 + $800 + $110 = $5,335 in Total Expenses
361,432 – 356,566 = 4,866 Total Miles

Just plug these two numbers into the formula:

$5,335 ÷ 4,866 miles = $1.09

So in this example, you’ve spent $1.09 for every mile you drove this month.

You have multiple trucks? Do the above calculations for every truck first, then use the same formula to get a fleet figure.

Truck 1 expenses came to $5,335, and the miles for the month came to 4,886.
Truck 2 came in at $4,438 with a total of 5,193 miles
Truck 3 was $6,109, and 5,532 miles

Total Expenses for all 3: $5,335 + $4,438 + $6,109 = $15,882
Total Miles for all 3: 4,886 + 5,193 + 5,532 = 15,611 miles

Cost Per Mile: $15,882 ÷ 15,611 miles = $1.02 spent for every mile traveled, collectively.

You see? It's pretty simple after you see it done.