Amazon – What you need to know about the new Selling Partner API (SP-API)


Amazon recently announced the launch of its new Selling Partner API. To replace the outdated MWS, this new API is an important opportunity for all brands and vendors who are concerned about their presence on the marketplace. At Lengow, our teams are currently developing this new API to make it available to our clients. Let’s take a look at how this major upgrade can be an asset and the changes to get ready for.

What is the Amazon Marketplace Web Service (MWS)?

For more than 10 years, Amazon Marketplace Web Service or MWS has been the preferred interface to access Seller Central and monitor anything to do with your Amazon store: sending products, managing orders, stocks, automatic modification of prices, etc. It is a strong tool but it required some sprucing up: this XML API is a design that was largely abandoned as time went by and APIs’ based on JSON gained popularity. Speed and capacity are limited and error management is time-consuming.

Make room for Selling Partner API (SP-API)

Selling Partner API (SP-API) is a modernized upgrade, with standards that are expected by developers today while simplifying the migration as much as possible compared to former API Amazon MWS. This new API is up and running with all the features from MWS with a dozen new APIs’ for Vendor Central.

Modernized API REST design standards based on JSON

  • The evolution of API call quotas in a dynamic way according to merchant’s needs over time
  • Better management of authentication and authorizations: authentication takes place with LWA (Login with Amazon), their OAuth 2.0 implementation
  • An API sandbox version (the most sought-after feature in MWS) in order to test it out before going into production
  • The very first API for Vendor Central (this is a model where you sell your items directly to Amazon who become the distributor of your products)

SP-API is also deployed with the aim to further automate the flow of data, sell more efficiently, automate manual processes, access Insights and predictions in terms of consumers’ purchase intentions, optimize advertising expenses, etc.

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What do I need to do?

No need to panic! The transition isn’t going to take place overnight: SP-API is available in all stores where Amazon MWS is supported. In the future, all the new features will be integrated into SP-API, with MWS updates only for critical changes for vendors’ business.

Therefore, there’s no obligation to migrate to SP-API for the time being, but we encourage you to analyze your current integration, in order to begin scheduling your migration.

Amazon SP-API + Lengow

At Lengow, our teams are currently reviewing this new API to start development in a few weeks.

  • Do you already sell on Amazon via Seller or Vendor Central?
  • Do you wish to be self-sufficient with respect to your technical teams?
  • Are you planning on getting started on the marketplace soon?
  • Are you responsible for managing APIs’ for a retailer, brand, or agency?

Given these various scenarios, our platform can help you handle this transition smoothly and ensure continuity when selling your products on Amazon… Why not make the most of the opportunity and test out other marketplaces?!

Get in touch!

Naomi Botting

Field Marketing Specialist

Your e-commerce library

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