According to the latest reports, there are now around 2 million small businesses across the globe selling through the Amazon eCommerce platform, making it one of the biggest online sales platforms in the world.
There are many reasons why companies choose to sell through Amazon, with one of the top reasons being that Amazon offers a broad range of features and selling tools that can help smaller brands to do more with less.
There’s no denying that Amazon offers everything that businesses need to sell successfully in the digital space and reach out to potential customers. However, it’s important to remember that no two organisations are the same.
Every business will always have its own needs and requirements, and it’s not always possible for Amazon to meet these needs at such an individual level. Sometimes, small brands need more.
The good news is that, while Amazon itself may not be able to tick every single box, it has a network of partners that can. So if you have ever wished you had access to more data, more insights, and more tailored support, the Seller Central API is just what you need.
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What is the Seller Central API?
Known as the Selling Partner-API (or SP-API for short), the Seller Central API was launched in September 2021 to replace the original Amazon Marketplace Web Service (MWS) API. The SP-API is an interface that allows approved selling partners to create tools to help them – or to help other sellers – manage their online sales efforts more easily.
A ‘selling partner’ can be any seller or vendor approved as a partner by Amazon. For the purposes of this guide, we’re going to focus on sellers, those who sell directly to customers through the Amazon platform.
The same interface is used for vendors – those who supply products to Amazon – although the process for setting up and using the API is a little different and is accessed through a Vendor Central account.
The API injects an additional layer of automation into selling on Amazon with a range of tools that are designed to free up more time for business owners to grow their brand.
For example, tools have already been developed to automatically price products according to pricing for similar ASINs, to alert brands when a competitor updates their ASINs, or to automatically engage in cross-selling opportunities as they arise.
The idea behind the SP-API is to enhance Amazon’s selling features to help businesses improve efficiency and boost customer service without hiring large teams.
Amazon charges a small fee depending on how many API calls are received and how much data is transferred out of the API gateway.
If you’re new to using the API, you can get a certain number of calls free per month for 12 months. After that, rates for REST APIs (representational state transfer) are typically between $1.51 and $3.50 (or currency equivalent) per million calls, depending on the number of requests received each month.
What Happened to MWS?

The former API, MWS, was discontinued in 2021 and replaced with SP-API. Much of the existing functionality was moved over to the new API, with a few additions:
- JSON-based REST API design standards
- OAuth2.0 selling partner authorisation (enabling login through Seller Central)
- Test endpoint
- Support for vendor API
If you previously used MWS, don’t panic! An application developed through the older system should still work as expected with SP-API, with no additional action required.
How to Use the Seller Central API
There are two types of developers who create valuable tools for Amazon:
- Private developers: These developers build tools to use for their own business
- Public developers: These developers build tools that other sellers can utilise
To start creating either private or public applications to support your efforts, you’ll need to register as a developer and have your dev account approved by Amazon.
The first step to using the SP-API is to sign in to your Seller Central account. If you already sell to customers directly through Amazon, you’ll already have this type of account. If you’re new to Amazon, don’t worry – setting up an account is very easy.
Visit the Seller Central registration page for the market you want to sell in (e.g. sellercentral.amazon.co.uk for Amazon UK or sellercentral.amazon.com for Amazon US) and follow the instructions for creating an account. But, first, you’ll need some information:
- Business address
- Payment option for monthly fees (typically a credit card)
- Valid ID (such as a passport)
- Company details, including VAT/tax information
When you’ve created your account, and you’re all signed in, you can register for a developer account right there through the Seller Central interface. It’s found at:
Seller Central > Partner Network > Develop Apps > Proceed to Developer Profile
You’ll now need to complete a form, which requires your contact details, data access, and use cases for the application you’re planning to develop. Everything is the same until this point in the process, whether you want to build public or private tools.
After completing the form, you can select the appropriate option:
- My organisation builds and offers publicly available applications (for public tools)
- I want to integrate to manage my own business only (for private tools)
Applications won’t be approved right away, so there may be a slight wait until you get started. But you can keep an eye on the status of your application on your Developer Central page, which you can access via the Partner Network menu.
If an application is denied, you can reapply by making the necessary changes and then re-submitting to Amazon.
Once approved, all that’s left to do is register your application. To do this, you’ll need to create an Amazon Web Services (AWS) account.
You can create a free account here. You’ll then need to add an Identity & Access Management (IAM) user within your AWS account, which is very quick and straightforward to do.
Just navigate to Users > Add User.
Distributing Public Applications
If you’re developing private applications to help grow your own business, you can start using them as soon as they are registered. But if you’re developing public applications that you’re opening up to others to use, you’ll need to distribute them.
You can do this by listing them in the Amazon Seller Central Partner Network (SCPN), a marketplace where Amazon sellers can find and install valuable tools to help them out.
Seller Central > Partner Network > Develop Apps > Add New App Client
Complete the form and decide who can access your tool: sellers, vendors, or both.
And that’s pretty much all there is to it. And if you decide to edit your application at a later date, you can navigate to Develop Apps > Edit app (don’t forget to click ‘save’!).
What’s great about the SP-API is that you only need to register once as a developer, regardless of how many applications you want to create or how many markets you want to offer them in; you won’t need to go through that initial form more than once.
When your tools are published in the SCPN, they’re available to whoever you’ve made them available to. Users can leave reviews or ratings for your applications – just like buyers can leave reviews and ratings for your products – to help others make the right decisions and select tools that can help them achieve their own sales objectives.
What If You Want to Use Applications Not Design Them?

Suppose you want to access useful applications to improve your Amazon selling process, but you don’t want to develop tools through the API. In that case, you don’t need to worry about registering as a developer. You will only need a Developer Central account if you plan to build your own tools or create tools for other sellers to use.
If you want to enhance the functionality of Amazon’s selling platform and find ways to automate your processes and meet your brand’s individual selling needs, all you need to do is head over to the Amazon app store and start browsing:
Seller Central > Partner Network > Find Apps & Services
Here, you can search directly for any applications that you’ve already heard positive things about, or you can browse the categories and look through individual tools.
What Can I Develop Through the API?
It’s entirely up to you. Currently, the Amazon SCPN covers eight distinct categories:
- Product launches
- Product listings
- Inventory management
- Order prep
- Customer engagement
- Branding
- Finances
- eCommerce management
And within these categories, a wide selection of sub-categories cover everything from feedback and reviews to A+ content, analytics & reporting, translations, and product scouting. As long as you remain compliant with the SCPN and SP-API regulations, there’s almost no limit as to what type of tools you can build and publish.
Ultimately, while Amazon is arguably the best platform for online sellers, every business needs tools to help them grow. By developing apps that can fill gaps in Amazon’s existing toolbox, you can support small businesses in reaching their goals.