Definition
An ERP system models a company's core commercial processes on a shared data foundation: article and customer master data, purchasing, inventory, order processing, shipping, invoicing and financial accounting. The point is that every department works from the same figures rather than maintaining separate islands. In e-commerce the ERP additionally holds the single truth about stock and pricing, from which all sales channels are supplied. It should be distinguished clearly from EDI: the ERP is where the data lives, EDI is the method by which it leaves the company in a standardised form.
Why it matters
As soon as more than one sales channel is in play, the ERP integration determines how far the business can scale. Without it, stock is maintained in several systems in parallel, which produces overselling and cancellations — on Amazon a direct risk to account health. With it, stock is maintained once and distributed outwards. The second lever is the order side: purchase orders that land in the ERP automatically need no data entry, and sales data flowing back makes replenishment planning and accounting possible without exported spreadsheets.
How it works
Connecting to Amazon works differently per model. In the vendor model (1P) it runs over EDI: Amazon sends purchase orders as X12 850 or EDIFACT ORDERS, and the supplier replies with acknowledgement, despatch advice and invoice. In the seller model (3P) there is no EDI — the SP-API applies, whether through a native ERP connector, a middleware provider or an in-house build. A third route is the broker or merchant-of-record model, in which a partner acts as the seller and absorbs the Amazon side, so the manufacturer's ERP serves a single interface rather than the requirements of each individual marketplace. Which route fits depends less on technology than on who can operate the marketplace processes on an ongoing basis.
Real-world examples
• A manufacturer maintains stock in JTL and distributes it to Seller Central through an SP-API connection; orders return automatically as sales orders. • A vendor receives Amazon purchase orders via EDIFACT straight into SAP and generates despatch advice and invoice from the same system. • A mid-sized company with no IT capacity for marketplace operations hands the Amazon channel to a broker and supplies only article data and stock over one interface. • Watch the ambiguity: when "ERP" appears in a compliance context it refers to Extended Producer Responsibility — packaging or WEEE registration — not to inventory management.
Common pitfalls
• **Equating ERP with EDI:** an ERP can be EDI-capable, but it is not itself EDI. A connection to a specific partner only exists once mapping and transport are in place. • **Maintaining stock twice:** the moment inventory lives in two systems, overselling is a question of when, not whether. • **Believing "Amazon connector included":** the scope of such connectors varies enormously. What matters is which transactions are actually supported — stock, prices, orders, returns, refunds — not whether a connector exists. • **Underestimating master data quality:** GTINs, packaging units and dimensions must be right before integration. Any integration multiplies existing master data errors rather than curing them.
Frequently asked
What does ERP stand for?+
ERP stands for Enterprise Resource Planning and refers to the central system for running core commercial processes — articles, inventory, orders, purchasing, shipping and accounting on a shared data foundation. In compliance contexts the same abbreviation means Extended Producer Responsibility and refers to something entirely different.
What is the difference between ERP and EDI?+
The ERP is the system where business data is held. EDI is the method by which documents are exchanged in a standardised form between two companies. Neither replaces the other: EDI draws data out of the ERP and delivers inbound documents back into it.
How do I connect my ERP to Amazon?+
It depends on the sales model. In the vendor model (1P) the connection runs over EDI using ORDERS, ORDRSP, DESADV and INVOIC — or their X12 equivalents 850, 855, 856 and 810. In the seller model (3P) it runs over the SP-API, via a native ERP connector, middleware or an in-house build. Alternatively, in a broker or merchant-of-record model a partner takes over the Amazon side, so the ERP only has to serve one interface.
Which ERP is best for Amazon?+
There is no universally best system. What matters is not whether a connector exists but which transactions it actually covers — stock, prices, orders, returns, refunds, VAT across multiple countries — and whether anyone in-house can run marketplace operations long term. Companies that can do neither are often better served by a partner model than by another software licence.