Making a test payment

The Sandbox settles deposits on public test networks, so you can run the full payment flow end to end without moving real funds. This guide shows how to fund a test wallet and pay a Sandbox invoice or channel.

We recommend testing with TRON — TRX (ttrx) and USDT on TRON (ttrx:usdt). Both run on the TRON Shasta testnet: confirmations are fast, fees are negligible, and test tokens are easy to obtain. ttrx:usdt also mirrors the most common production integration — stablecoin deposits.

Sandbox network codes are testnet-prefixed. ttrx and ttrx:usdt both map to the TRON Shasta testnet. See Supported currencies for the full list.

1. Install a TronLink wallet

TronLink is the most widely used TRON wallet and supports the Shasta testnet. It is available as a browser extension and a desktop app — choose whichever suits your workflow.

Browser extension

1. Open the TronLink website and choose your browser, or install directly from the Chrome Web Store or Firefox Add-ons.

2. Open the extension and select Create Wallet (or Import Wallet if you already have a test seed phrase).

3. Set a password and securely store your recovery phrase.

Desktop app

1. Download the desktop app for macOS or Windows from the TronLink website.

2. Install it, then create or import a wallet as above.

Use a dedicated wallet for testing. Never import a seed phrase that controls real funds into a test setup.

Switch to the Shasta testnet

1. Open TronLink and click the network selector at the top of the window.

2. Select Shasta (Shasta Testnet). Your balances and transactions now refer to the testnet rather than mainnet.

2. Get test tokens

You need a small amount of test TRX to cover network fees. For USDT tests you also need test ttrx:usdt.

• Public faucets. Follow TRON's Getting testnet tokens guide to claim Shasta TRX. Set your wallet to Shasta, then paste your address into the faucet.

• TRON Discord. Join the official TRON developer Discord (linked from the guide above) and request Shasta tokens in the faucet channel.

• From Txn. We can also send you test tokens directly — including ttrx:usdt. Contact your integration manager or email [e-mail] with your Shasta wallet address.

TRC-20 transfers (including ttrx:usdt) consume network fees paid in TRX, so keep some ttrx in the wallet even when testing USDT.

The Sandbox recognises a specific test USDT token (ttrx:usdt, contract TG3XXyExBkPp9nzdajDZsozEu4BkaSJozs). USDT from an unrelated test faucet may use a different contract and will not be detected — request ttrx:usdt from Txn if you are unsure.

3. Make the payment

1. Create a test invoice or channel via the API, using ttrx:usdt (or ttrx) as the payment network.

2. Copy the receiving address from the response. For invoices, also note the exact amountCharged — send that amount so the invoice completes as a full payment.

3. In TronLink (on Shasta), send the token and amount to the address.

4. Within a minute or two the deposit is detected: the invoice moves through its status flow, or the channel deposit appears in List channel deposits. If you have configured webhooks, you also receive the corresponding events.

Troubleshooting

• Payment not detected. Confirm the wallet is on Shasta (not mainnet or Nile), that you sent the correct token to the correct address, and that you are querying the Sandbox base URL (https://api.sandbox.txn.io). Testnet confirmations can take a minute or two.

• Transfer fails or "out of energy". Ensure the wallet holds some ttrx to cover the network fee.

• USDT sent but not credited. Check the token contract matches the Sandbox ttrx:usdt token above; tokens from unofficial faucets can differ.