Our Sandbox environment is designed to make it easy for you to test API calls in a safe, simulated version of Mercury — no real money involved.

Step 1: Sign up for a Sandbox account

First things first: you'll need a sandbox account.

Signing up skips the normal onboarding process. Your Sandbox account will come pre-loaded with dummy data including organizations, accounts, transactions, and account balances to allow testing.

Step 2: Create an API token (in the Sandbox)

Next, you’ll need an API token created specifically in the Sandbox environment. Go to the Sandbox dashboard after signing up.

Create a new API token from the UI.

Important: Tokens created outside of the Sandbox (like in production) won't work here.

Step 3: Direct your API requests correctly

When making API requests, make sure they’re pointed to our Sandbox base URL: https://api-sandbox.mercury.com/api/v1/

Any requests (like creating recipients, sending transactions, etc.) will show up in the Sandbox UI, so you can visually confirm what’s happening.

Quick Recap

  1. Use only Sandbox-created tokens
  2. Direct API calls to https://api-sandbox.mercury.com/api/v1/
  3. See your test data reflected in the Sandbox UI