3PL KPIs: 5 warehouse metrics to track, with formulas

The five 3PL KPIs most brands should track are order accuracy, on-time shipment rate, dock-to-stock time, inventory accuracy and billing accuracy. The first four measure how well the warehouse handles your stock and orders. The fifth measures how well it bills you, which matters because invoice errors cost money just like mis-picks do. Below is each formula, a worked example and the published benchmarks we could verify.

The five KPIs at a glance

KPI	Formula	Published benchmark
Order accuracy	Orders shipped without error ÷ orders shipped × 100	Best-in-class order-picking accuracy of 99.7% or more (WERC 2026)
On-time shipment rate	Orders shipped by the agreed cutoff ÷ orders due to ship × 100	Best-in-class 99.5% or more (WERC 2026)
Dock-to-stock time	Time available to sell − time delivered, averaged across receipts	Best-in-class under 3.1 hours (WERC 2026)
Inventory accuracy	Locations or SKUs where count matches system ÷ locations or SKUs counted × 100	No verified figure
Billing accuracy	Invoice lines billed correctly ÷ invoice lines checked × 100	No published benchmark found

The WERC figures come from the Warehousing Education and Research Council's 2026 DC Measures report, as summarized in a Yale white paper. "Best-in-class" there means the top 20% of respondents, and the survey covers distribution centers of all kinds, not only 3PLs serving e-commerce brands. Treat them as a high bar, not a typical result.

Order accuracy

Order accuracy = orders shipped without error ÷ orders shipped × 100

An error is a wrong item, wrong quantity, missing item or wrong address taken from your order. Count errors from customer complaints and returns coded "wrong item", plus any the warehouse reports.

Example: Juniper & Pine, a made-up brand, shipped 2,000 orders in a made-up month and traced 9 errors to the warehouse. Order accuracy = (2,000 − 9) ÷ 2,000 × 100 = 1,991 ÷ 2,000 × 100 = 99.55%.

Besides the WERC figure, The Fulfillment Advisor's 2026 survey reports that responding warehouses claimed 99.41% order accuracy on average. That is self-reported by warehouses, so measure your own.

On-time shipment rate

On-time shipment rate = orders shipped by the agreed cutoff ÷ orders due to ship × 100

Define "on time" in the contract, for example orders received by 1 p.m. ship the same business day. Measure from the warehouse's ship confirmation or first carrier scan, not from delivery, because carrier delays are a separate issue. WERC defines the measure as orders shipped at the planned time, meaning off the dock and in transit.

Example: Of 2,000 orders due to ship in the month, 1,968 shipped by the cutoff. On-time rate = 1,968 ÷ 2,000 × 100 = 98.4%.

Dock-to-stock time

Dock-to-stock time = time stock is available to sell − time it was delivered

Average it across all receipts in the month, or report the share of receipts completed within your contract's window. Dock-to-stock matters because stock sitting at the dock cannot be sold, and slow receiving often shows up later as backorders.

Example: A shipment arrives at 8:00 a.m. Monday and shows as available in the warehouse system at 11:00 a.m. Tuesday. That is 24 hours to 8:00 a.m. Tuesday plus 3 hours, so 27 hours.

The WERC 2026 best-in-class figure of under 3.1 hours reflects large distribution centers. Many 3PL contracts state receiving windows in business days instead, so set a target that matches your agreement.

Inventory accuracy

Inventory accuracy = locations (or SKUs) where the physical count matches the system ÷ locations (or SKUs) counted × 100

Track the unit variance too: total units over or short ÷ total units the system expected. A warehouse can have most locations right and still lose many units in a few.

Example: A cycle count checks 400 locations. 388 match the system. Inventory accuracy = 388 ÷ 400 × 100 = 97%.

We did not find a published inventory accuracy benchmark we could verify, so we have left one out. The Fulfillment Advisor's 2026 survey does report average inventory shrinkage of 0.12% among responding warehouses, again self-reported. Inventory count accuracy is in WERC's 2026 top 12 measures, but the summary we read gives no best-in-class figure for it.

Billing accuracy

Billing accuracy is rarely on a 3PL scorecard, but it is the KPI that shows up directly in your costs. Track two numbers:

Billing accuracy = invoice lines billed correctly ÷ invoice lines checked × 100

Credits as % of spend = credits owed for billing errors ÷ total 3PL spend for the period × 100

A line is billed correctly when the quantity matches the activity, the rate matches the rate card in effect on that date, and quantity times rate equals the amount.

Example: Juniper & Pine checks the fulfillment and storage lines of a made-up month: 1,180 lines, 23 of them wrong. Billing accuracy = (1,180 − 23) ÷ 1,180 × 100 = 1,157 ÷ 1,180 × 100 = 98.05%. The 23 lines were overbilled by $186.40 on a $9,320.00 bill, so credits owed as a share of spend = $186.40 ÷ $9,320.00 × 100 = 2.00%.

The two numbers tell you different things. Many wrong lines can be worth a few cents each, while a single wrong setting can be worth a lot. A shipping markup billed at 12% instead of 8%, for example, makes every shipping line wrong at once. Our cost per order guide shows that error adding $560.00 to one made-up month. Warehouse software vendor Extensiv suggests that 3PLs themselves track their dispute rate and the share of invoices needing adjustment, which is the same idea from the warehouse's side.

We found no published benchmark for billing accuracy, so use your own trend. Our guide to 3PL billing errors lists what to look for, and how to audit a 3PL invoice shows how to check lines.

Fill rate

Fill rate, sometimes called order fulfillment rate, is the share of orders shipped complete from stock on the first attempt. Red Stag Fulfillment's KPI guide gives the formula as orders shipped on the first attempt ÷ total orders × 100. It depends on your forecasting as much as on the warehouse, so use it alongside inventory accuracy rather than as a pure 3PL measure.

Building a 3PL KPI scorecard

Pick five or six KPIs from this page and write each formula down so both sides calculate it the same way.
Put targets in the contract or service level agreement, with the data source for each. Our 3PL contract checklist covers the billing clauses that sit next to them.
Agree the data feed. Ask for monthly exports of orders with ship times, receipts with arrival and available times, cycle count results and line-item billing detail.
Review monthly, with the trend over the last six months, not just the latest result.
Agree consequences. Credits per error, a root-cause review after a missed target, or a right to exit after repeated misses.

KPI	Target	This month	Notes
Order accuracy	From contract	99.55%	9 errors
On-time shipment rate	From contract	98.4%	32 late
Dock-to-stock time	From contract	27 hours	1 receipt
Inventory accuracy	From contract	97%	400 locations counted
Billing accuracy	From contract	98.05%	23 of 1,180 lines
Credits as % of spend	Track trend	2.00%	$186.40

Measure billing accuracy without the spreadsheet work

Billing accuracy is the hardest KPI to measure yourself, because it means checking every invoice line. 3PL Checker's free audit does that against your signed rate card and your Shopify orders, with a person reviewing every finding, so you get a starting figure for your scorecard.

Questions

What are examples of 3PL KPIs?

The core five are order accuracy, on-time shipment rate, dock-to-stock time, inventory accuracy and billing accuracy. Many brands also track fill rate, return processing time and cost per order.

What should a 3PL KPI scorecard include?

Each KPI with its formula, the target written into your contract, this month's result and the trend. Review it monthly with your 3PL and agree what happens when a target is missed.

What is order fulfillment rate?

Usually called fill rate, it is the share of orders shipped complete from stock on the first attempt. The formula is orders shipped complete on the first attempt ÷ total orders × 100.

What KPIs matter for a 3PL warehouse?

For a brand, the ones that affect customers and costs: order accuracy, on-time shipment, dock-to-stock time and inventory accuracy, plus billing accuracy, because invoice errors are a cost of working with a 3PL too.