A customer orders a product online that was just sold in the store. Yet the website still shows it as available. The result: the retailer has to cancel the order, let the customer know and fix the catalog by hand.
This problem often comes up when in-store and online sales don't share the same information. Inventory sync lets you track availability across your different sales channels from a single shared database. Here's how it works, and why it becomes essential as soon as a business sells on more than one channel.
What is inventory sync?
Syncing inventory means sharing availability data across several tools or sales channels, for example:
- a POS system;
- an online store;
- inventory management software;
- several locations;
- an order picking tool.
The goal is to keep each of them from working with different quantities. When a sale, a return or a goods receipt changes stock levels, the information needs to be updated in every system involved.
Why do stock discrepancies happen?
Sales recorded in separate tools
If your register and your e-commerce site use separate catalogs, each sale sometimes has to be entered again by hand. That double entry makes it easy to miss things.
Online orders accounted for too late
An item can still show as available when it has already been reserved for an order that's being prepared.
Unrecorded stock movements
Sales aren't the only operations that change quantities: supplier deliveries, returns, losses, breakage and inventory adjustments need to be taken into account too.
To understand where these differences come from, see also our article on inventory variance.
How does automatic inventory sync work?
Take a grocery store with ten bottles of the same product. All ten units are available in the store and visible on its website.
- A sale at the registerA customer buys two bottles in the store. The system records the sale and updates availability: eight units are left in stock.
- An online orderA few minutes later, another customer orders three bottles online. Depending on the business rules you've set up, those three units are reserved or deducted for the order.
- One shared, up-to-date inventoryThe quantity available for sale then drops to five, on both channels.
Shared information helps limit the gap between theoretical stock and the products actually available. This example assumes that both channels really do share the same inventory and that movements are passed on correctly.
Five conditions for reliable inventory sync
- Use consistent product referencesThe same product must be identifiable in each system: item codes, variants and units need to match.
- Define a source of truthYou need to decide which system is authoritative for available quantities. Without a clear rule, two tools can send conflicting information.
- Account for open ordersAn order that's confirmed but not yet picked up must be factored into your availability rules, especially for click & collect.
- Record every movementDeliveries, losses, returns and stock counts must all feed the same database.
- Check for discrepancies regularlyEven with automatic sync, errors can still slip through. Regular stock counts are still needed to compare system quantities with physical ones.
Can you manage several locations with synced inventory?
Yes, but you need to distinguish between two concepts. Total inventory is the full quantity a business holds. Inventory by location shows the quantities actually available in each store or warehouse.
A retailer with several stores needs to be able to keep a product that's in stock in Lyon from being shown as immediately available in Marseille. Multi-store management therefore calls for the right availability and allocation rules.
How does Gillia sync inventory and sales?
Gillia lets you connect your online store to your catalog, pricing and inventory data. When a sale is recorded on a connected channel, availability can be updated across the shared environment. You can also manage your online catalog's visibility from the same tool.
The AI agent can also help you check quantities, spot items at risk or prepare certain inventory tasks:
“Which online store items are almost sold out in my physical store?”
This approach brings together two complementary capabilities: inventory management with Gillia and the Gillia online store. Exactly how it works depends on which modules and integrations you've activated.
Key takeaways
Syncing inventory isn't just about showing the same number on two screens. You also need to centralize stock movements and set reliable availability rules. See how Gillia connects inventory management and online sales.
