Definition
A stockout is the lack of availability of a SKU (stock-keeping unit) when demand exists. It impacts fill rate, the In Full part of OTIF, and — in retail/industry — lost sales or line downtime.
If your “fix” for stockouts is raising every min, you are funding freight uncertainty with pallets.
Related: safety stock · inventory · OTIF.
What it means in practice
An empty location can be real (replenishment never arrived) or false (phantom inventory, miscounted location, allocation never released). Both look the same on a board without root cause.
On MX corridors, stockouts often start upstream: missed appointment, return empty that delayed inbound, or a broken warehouse-transport handoff.
Why it matters by role
| Role | What they lose | If they only “order more stock” |
|---|---|---|
| Sales / service | Incomplete orders | Bloated inventory without OTIF |
| Warehouse | Failed picks / broken waves | Masks WMS error |
| Procurement | Expedites and premium freight | Pays for uncertainty |
| Accounts payable | Uncontrolled express freight | No evidence match |
What to measure and record
| Field | Question | Note |
|---|---|---|
| SKU / ABC | How critical? | Prioritize A |
| Cause | Demand, lead time, count? | Classify |
| Fill rate | Complete lines? | Service KPI |
| Real lead time | Promise vs arrival? | With freight |
| Action | Replenish, substitute, hold? | Clear owner |
How to attack a stockout in 5 steps
Detect
Fill-rate alert
Classify cause
Phantom vs real
Contain
Substitute / prioritize
Fix lead time
Freight + appointment
Recalibrate buffer
Only if needed
Expensive mistakes
1.Raising mins blindly
You fund bad lead time. See safety stock.
2.Ignoring phantom inventory
The WMS lies and the stockout “returns” tomorrow.
3.Not tying to the inbound shipment
Without a trip ID you cannot tell freight failure from demand spike.
4.Measuring only at month-end
OTIF damage already happened.
OCL and the trip file
OCL helps surface delays and trip evidence that feed replenishment. It does not run your WMS or guarantee fill rate. OCL can stamp invoices and Carta Porte.
Sources and further reading
Key takeaways5 points
- Stockout = lack of SKU availability when demand exists; it hits fill rate, OTIF In Full, and lost sales or line stops.
- It is not only “WMS shows zero”: it includes phantom inventory, bad soft allocation, and late replenishment/freight.
- On Mexico–US lanes, unstable freight lead time turns a tight buffer into recurring stockouts.
- Connect stockout alerts to safety stock, procurement, and transport — not another spreadsheet.
- OCL does not calculate your EOQ; it helps stabilize lead-time evidence in the trip file. OCL can stamp invoices and Carta Porte.
Do your stockouts come from freight or from Excel?
Frequently asked questions
Lack of an available SKU when demand exists; it hits fill rate and OTIF In Full.
No. Safety stock is the buffer; a stockout is the event when the buffer (or process) failed.
Typically fill rate (lines or units served / demanded) and stockout counts by SKU/period.
Yes: unstable lead time and appointments empty the buffer even when demand is predictable.
Classify cause (phantom, demand, lead time) before buying more inventory.
Lead-time evidence and transport exceptions that explain recurring stockouts.