Pick and pack fee calculator: check your 3PL picking charges
Free pick and pack fee calculator. Enter orders, units and your first-item and additional-item rates to see what picking should cost and any overcharge.
This pick and pack fee calculator works out what your 3PL should have billed for picking in a month, from your orders, units and the two rates on your rate card. Compare the result with the picking total on your invoice. A positive difference means you were billed more than your rates allow.
How to use the calculator
You need five numbers:
- Orders shipped in the billing period. Take this from your Shopify order export: orders fulfilled by the 3PL in that period, without canceled orders.
- Total units shipped: the sum of item quantities across those orders.
- First-item fee and additional-item fee, from your rate card for the dates of the invoice.
- Amount billed for picking: the total of the pick and pack lines on the invoice, first-item and additional-item charges together. Leave packaging and postage out.
The formula
Expected = orders × first-item fee + (units − orders) × additional-item fee
Difference = amount billed − expected
Every order pays the first-item fee once. Every unit after the first in an order pays the additional-item fee, and units − orders is the total number of those extra units. If you enter fewer units than orders, the calculator treats the additional units as zero.
The formula assumes the common structure of one fee per order and one per extra item. If your contract uses a different structure, such as a flat fee per unit or tiers by order size, work from those terms instead.
Worked example
Ridgeline Fulfillment, a made-up warehouse, charges Juniper & Pine, a made-up brand, $3.25 for the first item and $0.65 per additional item from July 1, 2026. Before July 1 the additional-item rate was $0.85. These are examples, not market prices.
In a made-up month after the change, Juniper & Pine shipped 412 orders with 790 units. The invoice bills $1,660.30 for picking.
- First items: 412 × $3.25 = $1,339.00
- Additional units: 790 − 412 = 378
- Additional items: 378 × $0.65 = $245.70
- Expected: $1,339.00 + $245.70 = $1,584.70
- Difference: $1,660.30 − $1,584.70 = $75.60
The difference divided by the additional units is $75.60 ÷ 378 = $0.20, exactly the gap between the old $0.85 rate and the new $0.65 one. The billing system is still using the old rate. That is a certain finding, with the amendment as evidence.
What the result means
When the difference is positive, the cause usually shows in its size:
| What you see | Likely cause |
|---|---|
| The difference ÷ additional units equals the gap between two rates | An old rate is still in use after an amendment |
| The difference equals the picking charges of a few whole orders | Canceled orders billed, or orders billed twice |
| The difference ÷ additional-item fee is a whole number with no rate change | More items billed than the orders had |
| A large, irregular difference | Kits or bundles counted differently from the contract |
To confirm which, compare the invoice's order lines with your Shopify export order by order. Our pick and pack fees page explains each case, and kitting fees covers how bundles are usually counted.
A negative difference means you were billed less than expected. Some orders may fall on next month's invoice, or your units may include items the 3PL does not count, such as free inserts. Check before you rely on it.
A zero difference means picking matches your rates. The rest of the bill still needs checking: storage, receiving, packaging and shipping markup. The 3PL invoice audit checklist covers them all, and the 3PL cost calculator shows the whole month.
Check every order line
3PL Checker's free audit matches every pick and pack line on your invoices to your Shopify orders, so it finds canceled orders, extra items and old rates line by line, not just as a total. A person reviews each finding, and you get the evidence and a credit request ready to send.
Questions
What is a pick and pack fee?
It is what a 3PL charges to take the items in an order off the shelf and pack them for shipping. It is usually a fee per order that covers the first item, plus a smaller fee for each additional item.
How is pick and pack pricing calculated?
Expected picking charges = orders × first-item fee + (units − orders) × additional-item fee. Your rate card sets both fees and says what counts as a unit.
What is 3PL pick and pack?
Pick and pack is the core fulfillment work a 3PL does for each order: picking the items from storage, packing them with the right packaging and preparing the parcel for the carrier.
How much does 3PL pick and pack cost per order?
It depends on your contract and how many items your orders have. Enter your own rates and volumes in the calculator to get your figure.