How to use the result
A practical planning estimate
3PL proposals split costs across transaction fees, monthly charges, minimums, storage, receiving, projects, and postage. Converting the recurring pieces into a monthly total and cost per order makes quotes easier to compare and highlights which assumptions create the biggest swing.
Use a representative month or a 12-month weighted average for orders, items per order, returns, and shipping.
Translate every quoted fee into either a per-order, per-return, or monthly amount.
Run peak and low-volume scenarios to reveal minimums, storage growth, and seasonal surcharges.
3PL cost per order formula
Cost per order = max(monthly transaction fees + storage + receiving + account fees + shipping + other fees, monthly minimum) ÷ monthly orders
The result separates outbound shipping from fulfillment-only cost because postage often dominates the total. For a fair comparison, apply the same order profile and shipping assumptions to every provider.
Frequently asked questions
What is usually missing from a basic 3PL quote?
Common omissions include onboarding, integrations, receiving exceptions, carton disposal, long-term storage, inventory counts, projects, returns, peak surcharges, packaging materials, account minimums, and postage adjustments.
Should shipping be included?
Include it when comparing total cost to serve, but also track fulfillment excluding shipping so negotiated carrier rates do not obscure operational fees.
How should seasonal brands use the calculator?
Model separate low, average, and peak months. A single annual average can hide minimum charges in slow periods and labor or storage surcharges in peak periods.