InPost Pay API Implementation Checklist
To ensure a smooth onboarding process, we’ve prepared a list of key steps that will help you quickly integrate your store with InPost Pay.
Obtain sandbox access credentials
Fill in the form on the https://inpostpay.pl/kontakt page under the “For Business” -> “Sandbox” section and receive your access credentials.Review the API documentation
Go through our documentation available at InPost Pay – Developer Documentation – Confluence. There you’ll find detailed information about endpoints, methods, and response codes essential for the integration process.Read the implementation guide
The guide contains mandatory standards as well as optional placements where InPost Pay can be displayed. Choose those best suited for your store. Details can be found in InPost Pay implementation standards.Button on the product page (mandatory)
Button on the cart page (mandatory)
Thank-you page (mandatory)
Passing the parcel number (mandatory)
Configure all API functions and the widget
Set up and test all endpoints, including basket pairing, order submission, error handling, and exclusions. Start with the test environment to ensure everything works correctly.Authorization – implement authentication and authorization.
Frontend widget – integrate the InPost Pay Widget.
Backend widget – expose the endpoints described in the Merchant Backend API to support functionality according to sequence diagrams for InPost Pay and Widget 2.0.
Integration with InPost Pay (Basket App) – connect with the API methods described in the InPost Pay (Basket App) section.
Test the integration
Run end-to-end tests in the sandbox environment, verifying all features: payment flows, error handling, and notifications. Ensure that all required scenarios have been tested, as listed in InPost Pay Test Scenarios.Get access to the production environment
Once tests are complete, follow the link in Authorization and Technical Requirements to request production access.Submit your integration for audit
Agree on a date and time with us for the production launch. We’ll conduct two test transactions to confirm the correctness of the integration. If the audit is successful, your store will appear in the InPost Mobile app, and the integration will be considered complete.Integrate transactions and returns
Returns and transaction reviews can be managed via the Merchant Panel or integrated through the API. We recommend using the API. Details can be found in Returns and Transactions.Set up analytics tools (if applicable)
Frontend events generated in your store will continue to be recorded in your analytics tools as before.
If you want events emitted by the InPost Mobile app to also be included, use our prepared playbook. See InPost Pay – Analytics.Place InPost Pay banners in your online store
To let your customers know that InPost Pay is available, you can use our prepared assets: InPost Pay Store Materials.
InPost Pay Widget Visibility During Implementation and Testing
Important: While implementing and testing InPost Pay in the production store, the payment widget must remain hidden from regular customers. Visibility should be restricted only to testers and those involved in the rollout.
Goal:
Hiding the widget prevents potential customers from using an incomplete or non-functional version of InPost Pay. This minimizes the risk of negative user experiences and avoids issues caused by incorrect payment behavior.
How to achieve this:
Control widget visibility at the code or store configuration level. For example, implement an access authorization mechanism that allows the widget to be displayed only under a dedicated URL with a parameter, e.g.: https://shop.url?showInPostPay=true.
Restricted access: During testing, the InPost Pay widget should only be visible to selected users (e.g., filtered by IP address or test accounts).
Full activation: The widget should only be made available to all customers after successful completion of testing, audit approval, and full deployment of the service.