GrowthBnk Developer Portal

One API to accept payments across every aggregator and gateway. GrowthBnk orchestrates routing, retries and reconciliation server-side — you integrate once and stay gateway-agnostic.

Quick Start → API Reference

Introduction

The GrowthBnk API is organised around predictable, resource-oriented URLs and returns JSON responses. You create a payment, redirect the customer to a hosted checkout, then confirm the outcome server-side via the status endpoint or a signed webhook. Refunds follow the same request-signing model.

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Authentication

API key + per-request SHA-256 hash. Learn how requests are signed.

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Quick Start

Make your first payment in a few lines, in your language.

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Sandbox & Production

Test with UAT gateways and test cards — no real money.

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Webhooks

Receive signed, real-time payment events and verify them.

Base URLs

All API requests are made over HTTPS to one of two environments:

Environment	Base URL	Use
Production	https://api.growthbnk.com	Live traffic and real settlements.
Sandbox	https://sandbox.growthbnk.com	Integration testing with UAT gateways.

API Keys

Each merchant account is issued an API key and a secret salt. The key identifies your account and travels in the X-API-Key header; the salt is used to compute the request Hash and must never leave your server.

Keep your salt secret

Treat the salt like a password. Never embed it in browser, mobile or client-side code, and rotate it if it is ever exposed.

API Reference

Five core endpoints cover the payment lifecycle:

Endpoint	Method	Path
Initiate Payment	POST	/v1/route/initiate_payment
Transaction Status	POST	/v1/route/transaction-status
Cancel Transaction	POST	/v1/route/transaction-cancel
Refund Initiate	POST	/v1/route/refund-initiate/
Refund Status	POST	/v1/route/refund-status/

SDKs

Official SDKs wrap authentication, request signing, retries and webhook verification for you.

🐍 Python

pip install growthbnk

🐘 PHP

composer require growthbnk/sdk

🟢 Node.js

npm i @growthbnk/sdk

Error Codes

Errors use standard HTTP status codes and a JSON body with a human-readable message. See the full Error Codes reference.

Rate Limits

API traffic is rate-limited per API key to protect platform stability. If you exceed your limit the API responds with 429 Too Many Requests; back off and retry with jitter.

Need a higher limit?

Default limits suit most integrations. If you expect sustained high throughput, contact developers@growthbnk.com to raise your quota.

Webhooks

GrowthBnk posts a signed webhook to your configured URL when a payment reaches a terminal state. Verify the hash header before trusting the payload — see Webhooks.

Support

Questions or issues? Email developers@growthbnk.com or talk to our team.