How do I keep stock in sync across Shopify and Amazon?
Most Shopify-Amazon apps push a number outward well and pull sales back in slowly, which is exactly the gap that causes an oversell on one side or the other. Fixing it properly means both platforms reading live from one owned stock number, not two systems occasionally checking in on each other.
Why two-channel sync breaks down
Two platforms, two opinions on stock
Shopify knows what your storefront sold. Amazon knows what Amazon sold. Neither one has visibility into the other, so both are guessing at the true remaining count.
Inventory apps sync one direction well, not both
Most Shopify-Amazon apps are built to push Shopify stock outward. Pulling Amazon sales back in fast enough to stop a Shopify oversell is the part they tend to get wrong.
Amazon penalises the mistake, Shopify does not warn you
Amazon can suppress a listing or dent your account health for overselling. Shopify will happily let the order through with no idea Amazon already sold the last one.
FBA and merchant-fulfilled stock live in different places
If some stock sits in Amazon fulfilment centres and some sits in your own warehouse for Shopify, a simple one-number sync cannot represent both correctly.
Shopify and Amazon both read from the same number.
Neither platform holds its own copy of stock. A sale on either one deducts from a single owned figure, both storefronts see it immediately, and FBA versus merchant-fulfilled stock is represented correctly instead of blended into one misleading total. Amazon account health stops being a monthly worry.
Odoo owns the number, Shopify and Amazon just read it
We build the stock backend on Odoo, the open-source commerce ERP, and connect Shopify with our own connector and Amazon with a dedicated marketplace integration. Both platforms write to and read from the same Odoo stock figure in real time, so a sale on one is reflected on the other before the next customer can buy the same unit.
We build and maintain these connectors ourselves rather than reselling someone else's app, the same approach behind our own bol.com connector and the open-source bol.com API client we maintain for UK and NL sellers. When Amazon or Shopify changes an API behind your back, we are the ones who fix it, not a support ticket queue.
See how the pieces fit
Multichannel inventory & stock sync
The same problem across Shopify, Amazon, eBay, bol.com and a 3PL.
Odoo vs Linnworks
A full owned system versus a multichannel ops layer bolted onto separate accounting.
Shopify overselling
Why the oversell keeps happening, and what actually stops it.
Selling on more than two channels? See multichannel inventory and stock sync →
Ready to fix your ops?
Book a free discovery call. We'll look at your current setup and tell you honestly whether Odoo is the right move and what it would involve.