> ## Documentation Index
> Fetch the complete documentation index at: https://docs.lead.bank/llms.txt
> Use this file to discover all available pages before exploring further.

# Environments and Testing

> Understand Lead's sandbox and production environments.

Lead operates two environments — sandbox and production — with different behaviors around transaction auto-advance, settlement simulation, and daily processing windows. Understanding both helps you build against realistic conditions and avoid surprises at go-live.

## **Environments**

### **Sandbox**

The sandbox environment is available at [api.sandbox.lead.bank](http://api.sandbox.lead.bank). It is isolated from production and shares no data with it. Use sandbox to build and test your integration before requesting production credentials.

Key differences from production:

* **No auto-advance.** Transactions do not progress through statuses automatically. Use the /simulations endpoints to advance them manually. See [Sandbox](/get-started/sandbox) for the full list of simulation endpoints by rail.
* **KYC and OFAC not enforced.** Entity data is accepted without identity verification or sanctions screening.
* **International wires reach accepted only.** Full settlement simulation is not available for international wires in sandbox.
* **/simulations endpoints return 404 in production.** Do not call simulation endpoints from production code.

### **Production**

The production environment is available at [api.lead.bank](http://api.lead.bank). Credentials are provisioned by your Technical Account Manager after you complete sandbox testing and production go-live. [See Program Launch](/get-started/program-launch) for the milestone sequence.