*Source: Marketplace Ad Pros — canonical version at https://marketplaceadpros.com/guides/how-to-build-amazon-client-app-without-sp-api/*

# How to build an Amazon client app without the SP-API back end

## Can I build my own Amazon software without building the back end?

Yes. Build your screens on an Amazon data provider that already holds the Amazon Ads and Selling Partner API access,
and rent the plumbing. With Marketplace Ad Pros [Partner Connect](/amazon-partner-connect/), your clients connect
their Amazon accounts through links your product creates, come back to your product when they finish, and your
server hears about it by webhook. Your app reads their data through a REST API, with a separate key per client if
you want one. It costs $19 a month on top of a paid plan.

*Published by Marketplace Ad Pros, which sells Partner Connect. Where building it yourself is the better choice, this
guide says so.*

*Last updated: October 31, 2026*

## What "the back end" actually is

You want to give clients your own software, not run a data-infrastructure company. The screens are the easy part.
Behind them, an Amazon app needs:

- **API access.** Register as an Amazon Ads API developer and as an SP-API developer, accept Amazon's Data Protection
  Policy and Acceptable Use Policy, and get your apps reviewed.
- **Two OAuth flows.** Login with Amazon for Amazon Ads, and the Seller Central / Vendor Central authorization for
  SP-API, each by region.
- **Token storage and refresh.** Every client's refresh tokens, encrypted, refreshed on time, and a way to notice
  when a client revokes access or an authorization expires.
- **Report jobs.** Request reports, poll until they're ready, download, retry on rate limits, and backfill history.
- **A data model.** Reshape dozens of report types into something your app can query by client and date.
- **Upkeep.** Amazon changes report versions, endpoints and policies. Someone has to keep up.

That's months of engineering before your first client sees a screen, and it never stops needing attention.

## Build it yourself or build on a provider?

| | Build it yourself | Build on Partner Connect |
|---|---|---|
| Amazon developer registration and app review | You | Already done |
| OAuth, token storage, revoked-access handling | You | Done for you |
| Report scheduling, retries, backfills | You | Done for you |
| Name on Amazon's consent screen | Yours | Marketplace Ad Pros |
| Client connects from your product and returns to it | Yes | Yes |
| Webhooks when a client connects or access breaks | You build them | Included |
| A key that only reaches one client's data | You build it | Included on every paid plan |
| Cost | Engineering time plus hosting | $19/month add-on on a paid plan |

If your clients must see your name on Amazon's consent screen, or you need data Marketplace Ad Pros doesn't sync,
build it yourself. For most agencies the consent screen is a few seconds of a client's onboarding, and the rest of
the back end is the expensive part.

## How to build it, step by step

### 1. Decide what you build and what you rent

Build what clients pay you for: your dashboards, your workflows, your recommendations, your reports. Rent the
Amazon connections, token refreshes and report syncs. If a feature is "get the data from Amazon", it's on the rent
side.

### 2. Add Partner Connect to a paid plan

[Sign up](https://app.marketplaceadpros.com/signup), connect one Amazon account of your own to test with, and add
Partner Connect from Billing & Plans. It's $19/month ($5/week or
$190/year to match your plan's billing) on a paid AI Connect or optimization plan, and isn't
available during the two-week Launch period.

### 3. Set your return URL and webhook

Set the URL clients land on after connecting, and choose whether to skip our confirmation page so clients go from
your product straight to Amazon and back. Then add a webhook endpoint and store its signing secret; it's shown once.
Both can be done in the app or through the API:

```
PUT  /api/v1/connect-settings/
POST /api/v1/webhooks/
```

### 4. Create a connect link per client

Create a link with your own `state` (your client's ID, for example) and send the client its `url`:

```
POST /api/v1/connect-links/
{"name": "Client 42", "platform": "amazon_ads", "region": "NA", "state": "client-42"}
```

For Seller Central, send `country` (the marketplace, such as `US` or `DE`) instead of `region`. For Vendor Central,
also add `"account_type": "vendor"`:

```
POST /api/v1/connect-links/
{"name": "Client 42", "platform": "selling_partner", "country": "US", "state": "client-42"}
```

`name` is required and becomes the connection's name. When the client finishes, their browser
goes to your return URL with `link_id`, `state`, `success` and `error`, and your webhook receives
`connect_link.completed` or `connect_link.failed`. Treat the redirect as a signal, not proof: confirm with
`GET /api/v1/connect-links/{link_id}/` or the webhook. Webhook deliveries can arrive more than once or out of order.

### 5. Give each client its own API key and read the data

Create a REST API key on the Integrations page and limit it to that client's brands. That key only sees that
client's brands and profiles, so a bug or a leaked key in one client's pipeline can't reach another client. Keep
one key without a brand limit on your own backend for account-wide work: connect links, webhooks, connect settings,
integrations and changesets.

Then read the data:

```
GET  /api/v1/brands/
GET  /api/v1/profiles/
GET  /api/v1/profiles/{profile_id}/report-types/
POST /api/v1/reports/export/
```

Exports return up to 100,000 rows per call as CSV or JSON. Seller Central reports that cover a whole seller account
(orders, settlements, FBA fees) need a key that covers every brand on that Seller Central connection, which is the
normal case when each client connects their own.

## What your client sees

1. A "Connect Amazon" button in your product.
2. Amazon's sign-in and consent screen, naming Marketplace Ad Pros as the app they're authorizing.
3. Your product again, showing the connection.

Tell clients in your onboarding copy that Amazon will ask them to authorize Marketplace Ad Pros, your data partner.
Clients never need a Marketplace Ad Pros login.

## When this is the wrong approach

- **Your name has to be on Amazon's consent screen.** Partner Connect can't do that today; register your own Amazon
  apps and build the back end.
- **You want a ready-made branded portal, not an app you build.** Partner Connect has no branded copy of our web app.
  See [which Amazon agency software allows custom branding](/guides/amazon-agency-software-custom-branding/) for tools
  that ship branded reports or portals.
- **You need retailers other than Amazon.** Marketplace Ad Pros is generally available for Amazon only.

## Frequently asked questions

### Can I build my own Amazon app without getting SP-API approval?

Yes, if you build on a provider that already has it. With Marketplace Ad Pros Partner Connect, your clients authorize the Marketplace Ad Pros app on Amazon, and your product reads their data through its REST API. You build the screens; you don't register your own Amazon Ads or SP-API app, store tokens or schedule reports. The trade-off is that Amazon's consent screen names Marketplace Ad Pros, not you.

### Will my client see my brand when they connect their Amazon account?

Before and after Amazon, yes: the connect link starts in your product and returns to your URL, and you can skip the Marketplace Ad Pros confirmation page. Amazon's own consent screen shows Marketplace Ad Pros as the app being authorized, so tell clients to expect it.

### How much does it cost?

Partner Connect is $19 per month ($5 per week or $190 per year to match your billing), added to a paid AI Connect or optimization subscription. It isn't available during the two-week Launch period. Brand-limited API keys are included on every paid plan.

### Can each client's integration use its own API key?

Yes. When you create a REST API key you can limit it to specific brands, so a key only reaches that client's profiles and data. Account-wide endpoints such as connect links, webhooks, integrations and changesets need a key without a brand limit, so keep one of those on your own backend.

### Which Amazon data can my app read?

Amazon Ads (Sponsored Products, Sponsored Brands, Sponsored Display and DSP) and Seller Central or Vendor Central data, through report listings, freshness checks and bulk exports of up to 100,000 rows per call, plus campaign reads and updates with a read-write key.

## Related guides

- [Partner Connect](/amazon-partner-connect/)
- [Which Amazon agency software allows custom branding?](/guides/amazon-agency-software-custom-branding/)
- [Amazon Selling Partner API (SP-API) explained](/guides/amazon-selling-partner-api-sp-api-explained/)
- [How to get access to a client's Amazon Ads and Seller Central accounts](/guides/how-to-get-access-to-client-amazon-accounts/)
- [Developer REST API](/developer-api/)

## Sources

1. [Amazon Selling Partner API -- registration overview (developer profile, policies, app registration)](https://developer-docs.amazon.com/sp-api/docs/sp-api-registration-overview)
2. [Amazon Selling Partner API -- roles](https://developer-docs.amazon.com/sp-api/docs/roles-in-the-selling-partner-api)
3. [Amazon Ads API documentation](https://advertising.amazon.com/API/docs/en-us)

Partner Connect details were checked against the Marketplace Ad Pros API documentation on October 31, 2026.

---

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