There is a particular sinking feeling that comes from accepting an online order for the last jacket on the rail, only to discover a walk-in customer bought it an hour earlier. You now have to apologise, refund and hope the online buyer comes back. As businesses sell through more channels, keeping one accurate stock number becomes a real operational challenge.
Decide on one source of truth
The most important decision is which system holds the master stock count. Options typically include:
- Your point-of-sale system, if it has strong inventory features and the shop is your main channel
- Your ecommerce platform, if online is the larger channel and the POS is a connected add-on
- A dedicated inventory or ERP system, sitting between all channels and updating each one
Problems start when two systems each believe they are in charge. Pick one and make every other system read from it and report sales back to it.
Unified platforms versus integrations
Some platforms offer both online store and point-of-sale in one product, which makes synchronisation simple because there is only one database. This works well for many small retailers.
If you already have separate systems you are happy with, you will need an integration. That might be a ready-made connector, a middleware service or a custom-built link. When comparing approaches, ask:
- How quickly does a sale in one channel reduce stock in the other?
- What happens if the connection fails for a few minutes?
- Are variants such as size and colour matched correctly?
- How are returns, exchanges and damaged items handled?
- Can staff see a log of every change for troubleshooting?
Product identifiers must match
Sync fails most often because the same product is described differently in each system. Every sellable item, including each variant, needs a unique SKU or barcode used consistently everywhere. Before connecting systems, clean up duplicates, retire old codes and agree naming rules. This tidy-up is tedious but prevents a long tail of mysterious mismatches.
Use safety buffers wisely
Even with fast syncing, there can be brief gaps between a shop sale and the online count updating. A buffer, where the website shows fewer units than you actually hold, reduces the risk of overselling popular or low-stock items. You might hold back a small number for the shop or mark items as unavailable online when only one remains. Adjust buffers by product: a fast seller needs more margin than a slow one.
Handle the awkward cases
Real retail is messy. Plan for:
- Click and collect: reserve stock at the chosen location as soon as the order is placed.
- Returns: decide whether returned goods go straight back into sellable stock or into an inspection status first.
- Multiple locations: track stock per shop and per warehouse, and decide which locations fulfil online orders.
- Transfers: record moves between locations so counts stay correct during transit.
- Shrinkage and damage: give staff a quick way to adjust counts with a reason.
Keep counts honest
No sync is better than the numbers going into it. Regular cycle counts, where you check a portion of your range each week, catch drift before it causes problems. Train shop staff to scan every sale, including discounted and staff purchases, and to log breakages immediately.
Build or buy?
Off-the-shelf connectors suit common platform pairings and straightforward catalogues. Custom integration makes sense when you have an older POS, an ERP, several warehouses or unusual business rules. A custom link can also add alerts, such as notifying a manager when sync fails or stock drops below a reorder point. Our software development and automation teams build these connections regularly.
FAQ
Is real-time sync essential?
For fast-moving or low-stock items, near-instant updates matter. For slower ranges, syncing every few minutes is often enough, especially with sensible buffers.
What if my POS has no API?
You may need a scheduled file export, a middleware tool or, eventually, a POS upgrade. A developer can advise on the most reliable option.
Should online orders come from shop stock or a warehouse?
It depends on your volumes and staffing. Many retailers start with shop stock and move to a separate fulfilment location as online sales grow.
Next step
If overselling or manual stock updates are costing you time, Export Apps can connect your shop and online store properly. Contact us to explain your setup.