Marketplace stock sync is something every store that sells on more than one channel runs into sooner or later. Your own site matters for your brand and your customer relationships; marketplaces, such as the Turkish marketplaces Trendyol and Hepsiburada, bring ready-made traffic and trust. Running both makes sense, but if stock, prices and orders are updated by hand in three different places, selling an item that has already been sold, and seeing cancelled orders drag down your store rating, become inevitable. In this article we explain how sync should be set up and the mistakes we see most often.
The single source of truth rule
The first and most important decision in sync is where stock and prices are really kept. If every channel keeps its own stock, nobody ever knows which one is right. In a healthy setup there is one source, and the other channels are fed from it. That source is usually either the ERP or the e-commerce platform itself:
- If the ERP is the source: Warehouse movements are recorded in the ERP; the online store and marketplaces take their stock from the ERP. This is the most consistent route for the physical warehouse and for accounting.
- If the e-commerce platform is the source: In companies without an ERP, or whose ERP doesn't keep up-to-date stock, the platform becomes the hub; the marketplaces and the ERP are fed from it.
Whichever you choose, the situation where "stock gets corrected by hand in both places" has to go.
Stock sync: speed and a safety margin
How often should stock be pushed? There are two approaches: batch updates at set intervals, or an instant update whenever something moves. Fast-moving products need instant updates; for a large catalog of slow movers, batch updates at short intervals may be enough.
Even with instant sync, it is wise to set a safety stock for orders that arrive on two channels at the same moment. For example, while the last two units are sold on your own site, marketplaces can show "out of stock." This significantly reduces the risk of cancellations and penalties.
Price sync: same price, or channel prices?
Marketplace commissions and service fees differ from those on your own site. That is why many stores charge different prices per channel. Two rules make this easier:
- Generate prices from one place, using rules. Instead of entering prices by hand for each channel, define channel rules based on the main price (such as adding a set percentage or amount).
- Plan campaigns per channel. A campaign on one marketplace should not automatically change the price on your own site; it should be clear which campaign applies where. We covered the effect of campaign design on margins in our article on campaigns that don't erode your margin.
Order flow: bringing it all onto one screen
Just as important as stock and price sync is collecting orders in one place. Logging into each marketplace panel separately to check orders and printing shipping labels one by one costs time and causes errors. In a good setup:
- Orders from all channels appear in one list, together with their source channel.
- The moment an order comes in, stock drops on every channel.
- The shipping label and tracking number are generated in one place and reported back to the relevant channel. For this part, see our shipping integration guide.
- The order is transferred to the ERP for invoicing.
Product matching: the overlooked foundation
The most common reason sync quietly breaks down is product matching. If the product code on your site, the product code on the marketplace and the stock code in the ERP aren't correctly linked to one another, stock gets written to the wrong product. Especially for products with variants (size, color), each variant needs its own permanent code. The barcode or stock code should be used as the single key and should never be changed afterwards.
Sync checklist
| Topic | Healthy state |
|---|---|
| Stock source | One system; the others are fed from it |
| Update frequency | Instant for fast-moving products |
| Safety stock | Defined for items running low |
| Price | Main price + channel rule |
| Orders | On one screen, with channel information |
| Product code | Unique and permanent for every variant |
| Error tracking | Failed transfers are reported and notified |
The last item is often skipped. Sync will fail at some point; what matters is that the failure is logged in a way that someone finds out about it.
How do we do it at Globya?
On the IMFLEXI platform, marketplace product, stock, price and order sync is built in; together with the ERP connection, we agree with you at the start of the project which system will be the source. If you use a different platform, we handle building a bridge between your existing systems as part of our integration service. For our general approach on the retail side, take a look at our retail and e-commerce page.
Frequently asked questions
If I sell on marketplaces, do I need my own site?
Marketplaces bring ready-made traffic, but the customer relationship, the brand and the rules belong to the marketplace. Your own site is the channel where you build a direct relationship with customers and set the rules yourself; the two are not alternatives but complements.
Does sending products via XML count as sync?
Partly. An XML feed transfers product and stock information at set intervals; for orders and instant stock deductions, you usually need a two-way connection through the channel's API (the door through which systems exchange data).
What happens if a sync error occurs?
In a well-built setup, a failed transfer is logged and retried, and if it keeps failing, the responsible person is notified. A sync that fails silently is more dangerous than no sync at all.
I have more than one warehouse. Does sync support that?
In the right setup, stock is kept per warehouse, and you can decide separately which warehouse's stock is made available to each channel.
The Globya assistant is online 24/7; it answers right away and passes your question to the team if needed.