Overview

Amazon will deactivate the final Marketplace Web Service (MWS) endpoints in early 2024, ending support for the legacy API that many sellers still use for private integrations. Any custom‑built tool that relies on MWS will stop working once the shutdown occurs, threatening inventory syncs, order processing, and reporting. Sellers must migrate those applications to the Selling Partner API (SP‑API) or replace them with an Amazon‑approved third‑party solution immediately.

Key Points

• MWS shutdown date announced — Amazon has set a firm cut‑off for the remaining MWS endpoints, after a multi‑year deprecation schedule.
• Private apps will fail — Custom scripts that pull orders, update stock, or generate dashboards will return authentication errors once MWS is disabled.
• Two migration routes — Sellers can either rebuild their integration on SP‑API or adopt a ready‑made app from the Amazon Appstore that already uses SP‑API.
• Third‑party apps are safe — Vendors such as Helium 10, Jungle Scout and SellerBoard completed their migrations, so users of those platforms face no interruption.
• High‑volume sellers at greatest risk – Those who depend on bespoke automation to handle thousands of SKUs or daily order spikes will experience the most severe disruption if they do not act.

How SP‑API Migration Works

1. Register as a developer — Log into Seller Central, navigate to the “Developer Profile” page, and create a new developer account. Example: A seller who previously used a freelance developer registers themselves, receives a developer ID, and can now create SP‑API applications.
2. Create a new SP‑API application — Within the developer console, click “Add a new application,” provide a name (e.g., “MyInventorySync”), and generate the required OAuth 2.0 client credentials. Example: The generated client ID and client secret replace the old MWS access key and secret key in the code base.
3. Configure OAuth 2.0 permissions — Select the specific scopes needed for your workflow, such as , , or .