How to Read Fulfillment Reports: Inventory Aging, Turnover & KPIs

Staring at fulfillment reports and feeling lost?
Seeing rows of numbers but not sure what matters?
Wondering why inventory looks “healthy” but cash feels tight?

I’ve been there.
And I’ve helped plenty of sellers work through this exact problem.

Fulfillment reports are not paperwork.
They’re decision tools.

Once you know how to read them,
they tell you what to restock,
what to cut,
and where money is leaking.

Let’s walk through this step by step.
Simple words.
No finance jargon overload.

Why Fulfillment Reports Matter More Than You Think

Fulfillment reports sit between operations and profit.

They answer questions like:

• Why is storage cost rising?

• Why are bestsellers still out of stock?

• Why does cash feel stuck?

If you ignore these reports:

• Inventory piles up

• Slow movers eat margin

• Fast sellers get understocked

Reading reports well = better cash flow and fewer surprises.

The Core Fulfillment Reports You Should Actually Care About

You don’t need every report.
You need the right ones.

Focus on:

• Inventory aging

• Inventory turnover

• Core fulfillment KPIs

These three tell 80% of the story.

Inventory Aging: Where Your Cash Is Sleeping

What Inventory Aging Means

Inventory aging shows how long products sit in storage.

Usually grouped like:

• 0–30 days

• 31–60 days

• 61–90 days

• 90+ days

The longer inventory sits, the more it costs you.

Not just storage fees.
Opportunity cost too.

How to Read Inventory Aging the Right Way

Don’t panic over older inventory.
Look for patterns.

Key things I check:

• What % is over 90 days?

• Are slow movers seasonal or permanent?

• Are top SKUs aging faster than expected?

Red flag:
More than 25–30% of stock in 90+ days.

That usually means:

• Over-ordering

• Poor forecasting

• Weak product-market fit

What to Do With Aging Inventory

Practical actions:

• Bundle slow movers with fast sellers

• Run clearance campaigns

• Pause reorders immediately

• Adjust future MOQ (minimum order quantity)

Aging inventory is not a failure.
Ignoring it is.

Inventory Turnover: Speed Beats Volume

What Inventory Turnover Is

Turnover shows how fast inventory sells and gets replaced.

Simple idea:

• Higher turnover = healthier business

• Lower turnover = cash tied up

Basic formula:

• Cost of goods sold ÷ average inventory value

You don’t need perfect math.
You need direction.

What Good Turnover Looks Like

This depends on your category.

Rough guidelines:

• Fast-moving consumer goods: higher turnover

• Branded or seasonal products: moderate turnover

• Custom or niche items: lower but stable turnover

What matters most:

• Consistency

• Improvement over time

If turnover is dropping quarter by quarter,
something’s wrong.

How Turnover Connects to Fulfillment Costs

Low turnover causes:

• Higher storage fees

• More aged inventory

• Slower cash recovery

High turnover gives you:

• Faster restock cycles

• Better negotiating power

• Cleaner fulfillment operations

This is why turnover is a KPI, not just a metric.

Fulfillment KPIs You Should Track Weekly

KPIs turn reports into decisions.

Here are the ones I actually use.

1. Order Fulfillment Rate

This tells you:

• How many orders ship without issues

Low rate usually means:

• Stockouts

• Poor inventory sync

• Picking errors

Target:

• As close to 100% as possible

2. Average Fulfillment Time

This is:

• Order placed → order shipped

Watch for:

• Spikes during holidays

• Delays during peak seasons

If time increases:

• Customer satisfaction drops

• Refund risk rises

3. Storage Cost per Unit

This one is often ignored.

Track:

• Monthly storage cost ÷ units stored

If this keeps rising:

• Inventory aging is hurting you

• SKU mix needs fixing

4. Inventory Accuracy Rate

This measures:

• System stock vs physical stock

Low accuracy causes:

• Overselling

• Emergency shipments

• Customer complaints

Accuracy issues compound fast.

5. Return Rate by SKU

Returns are expensive.
Especially internationally.

Track:

• Which SKUs get returned

• Why they’re returned

Then fix the root cause:

• Packaging

• Product description

• Quality control

  
  

A Quick Story From the Real World

One seller I worked with was confused.

Sales were stable.
But storage fees kept climbing.

We opened the inventory aging report.

Turns out:

• 20% of SKUs hadn’t sold in 4 months

• They were still reordering them automatically

We paused those SKUs.
Cleared old stock.
Reallocated cash to top sellers.

Three months later:

• Lower storage costs

• Faster turnover

• Same revenue, better margins

The data was there the whole time.

How Often You Should Review Fulfillment Reports

You don’t need daily obsession.

My rule:

• Weekly: KPIs

• Monthly: inventory aging & turnover

• Quarterly: SKU-level decisions

Consistency beats intensity.

Common Mistakes Sellers Make

I see these constantly.

Avoid them:

• Looking only at sales reports

• Ignoring aging inventory

• Tracking too many KPIs

• Reacting without context

Reports don’t tell you what to do.
They show you where to look.

FAQs: Real Questions Sellers Ask

1. How much aged inventory is too much?

If over 30% sits past 90 days,
you should act immediately.

2. Is low turnover always bad?

Not always.
Premium or seasonal products can turn slower.
The key is predictability.

3. Should I discount aging inventory fast?

Not blindly.
Test bundles or targeted offers first.

4. How accurate should fulfillment reports be?

Ideally above 98%.
Anything lower needs investigation.

5. Do small sellers really need KPIs?

Yes.
Even more than large sellers.
Mistakes cost more when margins are thin.

Final Thoughts

Fulfillment reports are not boring.
They’re powerful.

Inventory aging shows where cash is stuck.
Turnover shows how fast you recover it.
KPIs show where systems break.

You don’t need fancy tools.
You need attention and consistency.

Once you read these reports well,
you stop guessing
and start running fulfillment with confidence.