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Prove your first settlement on testnet

This walkthrough is pending subject-matter-expert review. The steps stitch together existing, individually maintained guides; the end-to-end sequence has not yet been verified by an engineering SME. Treat contract addresses and faucet sources as authoritative only at their linked sources.

This walkthrough is for the Settle on Arbitrum One path. It does not introduce new tooling. It connects the network setup, funding, transfer, and confirmation steps you already have into one payment-shaped flow, so you can prove a stablecoin settles end to end on testnet before you integrate it.

You run the whole flow on Arbitrum Sepolia, the public testnet, so no real funds are involved.

What you will prove​

By the end you will have sent a USDC transfer on Arbitrum Sepolia and confirmed that it settled. That is the smallest complete unit of a payment: value moved from one address to another and verified as final.

Prerequisites​

  • A wallet (such as MetaMask) you can point at a custom network.
  • Node.js and npm, if you follow the application-based transfer in step 3.

Step 1 — Point your wallet at Arbitrum Sepolia​

Add the Arbitrum Sepolia network to your wallet using the chain ID and RPC endpoint from the network reference. Do not copy these values from elsewhere — use the maintained reference:

Step 2 — Fund the account​

You need two things in the sending account:

  1. Testnet ETH to pay gas. Use a faucet for Arbitrum Sepolia listed in Chain info.
  2. Testnet USDC to transfer. Get it from Circle's faucet.

Confirm both balances appear in your wallet on Arbitrum Sepolia before continuing.

Step 3 — Send a USDC transfer​

Send the transfer one of two ways:

  • From a wallet: send a small USDC amount to a second address you control. This is enough to prove settlement.
  • From an application: follow the USDC quick start guide, which builds a small app that connects a wallet and sends a USDC transaction. Point it at Arbitrum Sepolia rather than mainnet.

Use the USDC contract address for Arbitrum Sepolia from Circle's official documentation. Do not hardcode an address taken from this page.

Step 4 — Confirm settlement​

Look up the transaction hash in the Arbitrum Sepolia block explorer (linked from Chain info) and confirm the recipient balance changed.

To understand when a transaction is final — and what finality means relative to the parent chain — read Transaction lifecycle. This is the difference between "the transfer was accepted" and "the transfer has settled," which matters once you reconcile payments in production.

Next steps​

  • Move from testnet to mainnet with USDC on Arbitrum One, which covers native versus bridged USDC.
  • Review Gas and fees so your cost model reflects mainnet conditions.
  • Return to the Payments page for the application and dedicated-chain paths.