A manufacturer storing its own stock has an inventory problem when its records are wrong.

A 3PL has an inventory problem and a customer problem.

That distinction is important.

Third-party logistics providers are trusted to hold, manage and account for inventory belonging to somebody else.

When the customer asks whether a pallet is present, where it is stored or why a discrepancy exists, a response of “that's what the WMS says” may not always be enough.

The strongest 3PL inventory control processes can provide evidence that system records have been physically verified.

Why inventory accuracy matters for a 3PL

For an owner-operated warehouse, an inventory discrepancy normally remains an internal operational issue.

For a 3PL, it can affect:

• customer confidence
• service-level performance
• claims and disputes
• account-management time
• financial write-offs
• contract renewal discussions
• operational reputation

The customer may not have direct visibility of the physical warehouse.. In this case, they are relying on the 3PL's systems and controls.

Inventory accuracy is therefore part of the service.

The WMS is essential, but the customer is really asking about physical reality

A WMS provides the digital record. It records receipts, moves, picks, replenishment and dispatch activity, but when a customer asks:

“Is pallet 123 actually there?”

they are asking a physical question.

The answer may be based on a system record.

A stronger answer is based on recent physical verification of that location.

That difference becomes especially important when there is disagreement between 3PL and customer.

What causes 3PL inventory disputes?

Inventory disputes can arise from many situations.

1. A customer expects stock that cannot be found.
2. A pallet is in the warehouse but stored in the wrong location.
3. A receipt quantity is challenged.
4. A pallet appears to have moved without a matching record.
5. An expected-empty location contains inventory.
6. A warehouse record and a customer's own ERP disagree.

At this point, historical evidence becomes extremely valuable. Without it, the investigation can become a reconstruction exercise.

Teams review transaction logs, speak with operators, check nearby locations and attempt to determine when reality moved away from the WMS record.

Physical verification changes the conversation

Suppose a customer challenges the location of a pallet.

If the last physical verification was six months ago, the investigation window is enormous. Conversely, if the location was independently checked recently, the situation is very different.

Recent evidence can tell the 3PL:

• whether the expected pallet was present
• whether another pallet was observed
• whether the location was empty
• when the discrepancy first appeared
• whether the issue is isolated or part of a pattern

The objective is not simply to win disputes; it is to resolve them faster and with greater levels of confidence and transparency.

Inventory accuracy should include coverage

A customer may be told that their warehouse inventory accuracy is 99.8%.

That sounds excellent.

But sophisticated customers can reasonably ask what the figure represents. The following questions are not uncommon:

Was all of our inventory checked?

How recently?

Were high-level pallets included?

Was the percentage based on quantities or locations?

What happened to the exceptions?

For a 3PL, reporting verification coverage alongside accuracy can create a much stronger proposition.

For example:

• percentage of customer locations physically verified
• date range of verification
• location accuracy
• exceptions found
• exceptions resolved
• outstanding investigations

This turns inventory accuracy from a "claimed figure" into an evidence-backed service metric.

Customer SLAs and physical stock-count obligations

Some 3PL contracts require a defined percentage of inventory to be counted or verified within a specific period.

Meeting that obligation manually can become a significant operational workload, particularly in high-bay warehouses.

The challenge is not merely completing the counts, it is being able to demonstrate that the required coverage was actually achieved.

A strong verification process should therefore make completed coverage visible and auditable. This is particularly valuable where customers have different service requirements within the same site.

High-level inventory can create an assurance gap

A common practical challenge is accessibility.

Lower rack levels can often be checked on foot.

Higher levels may require additional equipment, safety controls and time.

For a 3PL, that creates an uncomfortable question:

Should the customer have less confidence in stock simply because it is stored higher in the racking?

Ideally, no.

Verification coverage should reflect customer and operational risk rather than the convenience of manual access.

Earlier discrepancy detection improves customer service

A discrepancy discovered proactively is fundamentally different from one discovered by a customer order.

Consider two scenarios.

Scenario one

A picker cannot find a customer pallet.

The order is already waiting.

Stock control is called.

The customer is informed of a delay.

An investigation begins under significant time pressure.

Scenario two

A routine physical verification identifies the same misplaced pallet before it is needed.

The exception is reviewed.

The system is reconciled before the next order requires the stock.

The underlying discrepancy is identical. The customer experience is not!

This is why verification frequency matters commercially as well as operationally.

Evidence can strengthen customer relationships

For a 3PL, inventory assurance often becomes a differentiator.

Rather than merely reporting an accuracy percentage, the 3PL can demonstrate the process that supports it.

That may include:

• repeatable physical verification
• broad warehouse coverage
• evidence of completed checks
• direct WMS comparison
• exception reporting
• trend visibility
• clear discrepancy ownership

This gives the customer greater confidence that inventory problems are being found and addressed proactively rather than waiting to surface during a fulfilment event.

Inventory assurance in practice

RAWview customer PD Ports has discussed using regular automated inventory checks both to identify stock discrepancies and to provide customers with stronger evidence around inventory accuracy.

That distinction is important.

The inventory control process is not just about reducing internal warehouse effort; it can strengthen the evidence behind the service a 3PL provides to its customers.

From inventory accuracy to inventory assurance

For a 3PL, a reported accuracy figure answers:

“How many records were right when we checked them?”

Inventory assurance goes further.

It asks:

• How much customer inventory is physically verified?
• How frequently?
• Are difficult locations included?
• Is there evidence?
• How quickly are discrepancies identified?
• Who owns their resolution?
• Can performance be demonstrated over time?

Those questions align much more closely with what the customer really wants:

Confidence that their inventory is where the 3PL says it is.

Where autonomous inventory verification fits

Manually increasing verification coverage across a large high-bay 3PL operation can be costly.

The more customer locations that need checking, the greater the labour requirement.

Autonomous inventory verification separates physical data collection from that manual effort.

Locations can be checked routinely and compared against WMS expectations while stock control teams focus on the exceptions that actually require investigation.

For a 3PL, the outcome is not simply automation.

It is a more scalable way to provide inventory assurance.

Assess the strength of your customer inventory controls

RAWview's free Inventory Assurance Health Check helps 3PL and warehouse operators assess verification coverage, frequency, reconciliation, evidence, exception management and governance.

It can help identify where the current process is already strong and where greater physical verification could reduce operational or customer exposure.

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Frequently asked questions

What is a good inventory accuracy rate for a 3PL?

The target depends on the customer, contract and way inventory accuracy is measured. The percentage should be considered alongside physical verification coverage, frequency and the way exceptions are handled.

How can a 3PL prove inventory accuracy to customers?

A 3PL can strengthen evidence by retaining records of physical verification, showing what proportion of customer inventory was checked, comparing observations with WMS records and documenting the resolution of discrepancies.

Why is inventory verification important for 3PL customer service?

Earlier physical verification can expose misplaced or missing inventory before it causes a failed pick, replenishment delay or customer query. This allows problems to be resolved proactively rather than reactively.