Purchasing & suppliers
Total Cost of Ownership (TCO)
By the Supply Chain Manager team · Updated October 16, 2026
Total cost of ownership (TCO) is every cost of buying from a supplier, such as freight, duties, quality issues and stock held for its lead time, not just price.
The cheapest unit price is often not the cheapest supplier. A longer, less reliable lead time means more safety stock; poor quality means returns and rework; small MOQs or better terms save cash. TCO puts them on one scale.
How to calculate total cost of ownership
TCO = Purchase price + Freight & duties + Inventory carrying cost + Quality & returns cost + Ordering & admin cost
Total cost of ownership example
Illustrative numbers: supplier A is $10.00 a unit with a 30-day lead time; supplier B is $10.40 with 7 days. At 1,000 units a month, A's extra lead time means holding roughly 770 more units in transit and buffer. At a 25% carrying rate that is about $1,900 a year, against $4,800 a year more paid to B. A still wins on cost, but by much less than the price gap suggests.
Why total cost of ownership matters for distributors
TCO keeps supplier choices from being made on unit price alone, which is how many distributors end up with long, unreliable supply chains for small savings.
Common total cost of ownership mistakes
- Comparing suppliers on price per unit only.
- Ignoring the safety stock a long lead time forces you to hold.
Examples on this page use made-up round numbers to show the calculation. They are not benchmarks or results from real businesses.