FIELD NOTES / Inventory
How to investigate Shopify low stock and overselling alerts
A low number is useful only when you know what it measures. Shopify distinguishes inventory states and locations. Before treating a variant as at risk, check available stock, recent sales, and whether a shortage belongs to one location or the whole included inventory pool.
Watchwick flags negative available stock at any included location, or a fast-selling variant whose total available stock across included locations reaches its safety-stock threshold.
Start with available inventory
Available inventory is the quantity Shopify reports as available to sell. It differs from on-hand, committed, and incoming quantities. A shipment expected next week does not necessarily solve an order that needs stock today. Compare the inventory states in Shopify before explaining the finding to your fulfillment team.
Check the exact variant and SKU, then inspect each included location. A store-wide total can hide a shortage at the warehouse assigned to an order. Conversely, a low count at one location may coexist with usable stock elsewhere, depending on your routing and transfer process.
Understand the two stock checks
The overselling check flags negative available stock at any included location as High severity. It does not require recent sales to pass a fast-seller threshold. A negative location still matters when another location has enough stock to make the combined total positive.
The low-stock check is different: Watchwick adds the variant’s available units across included locations and compares that total with safety stock. It applies only when no included location is negative and the variant meets the configured recent-sales threshold.
Defaults are five available units for safety stock and at least five units sold in the last seven days for a fast seller. You can change both values, define safety stock for individual SKUs, and exclude locations. The recent-sales calculation uses non-cancelled, non-test orders; it is not a demand forecast or a supplier lead-time model.
Investigate before changing the count
A finding tells you what Shopify reports. The cause may be a real shortage, an unrecorded receipt, an inaccurate count, or an inventory policy that permits continued sales. Confirm the cause before choosing a response.
- Open the affected variant in Shopify Admin and compare available stock at each relevant location with the incident evidence.
- Check whether incoming stock, committed orders, or a pending inventory update explains the difference between physical stock and the available quantity.
- Review the variant’s inventory tracking and ‘continue selling when out of stock’ setting against your intended backorder policy.
- Identify the person responsible for a stock count, replenishment decision, transfer, or fulfillment plan, and confirm the revised source data afterward.
Tune the rule to the operation you have
Choose a safety threshold that gives your team enough time to investigate. A universal threshold can be too noisy for slow variants and too late for fast ones. SKU overrides let you reflect known differences, but Watchwick does not automatically calculate reorder quantities or predict a guaranteed stockout date.
The stock monitor covers active products with tracked inventory. It checks Shopify’s current reported levels and does not offer a historical stock-level preview. The landing-page inventory example uses one warehouse for clarity; the real low-stock calculation aggregates all locations remaining after exclusions.
Watchwick links the evidence to your team’s workflow and remains read-only. Stock corrections, purchase orders, transfers, sales-policy changes, and customer communication remain decisions and actions in your existing systems.
Further reading
These guides describe Watchwick’s current monitor behavior. For Shopify’s own terminology and workflow details, refer to its official documentation.