The credit-only model
A cardholder’s spending power equals the collateral backing their account. There is no stored prepaid balance: you deposit collateral to set a credit limit, and charges draw against that limit as the cardholder spends. Deposit more collateral to raise the limit. How you hold that collateral depends on your management model. In Rain-Managed programs, each user has their own smart contract. In Partner-Managed programs, you hold collateral at the account level. See Flow of funds for the difference.Fund a Rain-Managed program
In a Rain-Managed program, you deposit collateral into each user’s smart contract:1
Get the user's contract address
Call Get smart contract information
to retrieve the deposit address, chain, and accepted tokens.
2
Deposit supported tokens on-chain
Send supported tokens, for example USDC, to the deposit address on the
specified chain.
3
Confirm the credit limit
The credit limit updates automatically within minutes. Check it with
Get a user’s credit balances.
Fund a Partner-Managed program
In a Partner-Managed program, you hold collateral in your Rain account rather than per user. Add collateral from the dashboard with Add tokens, funding by wallet or Safe. Rain deploys a collateral contract per chain that serves as your reserve balance. As cardholders spend, charges post to your account, and you pay them off by ACH or crypto. For payment options and balance management, see Partner-Managed programs.Supported chains and tokens
Rain accepts USDC and USDT as collateral across supported chains, including Polygon, Base, Arbitrum, Optimism, Avalanche, Celo, BNB Smart Chain, ZKsync, Solana, Plasma, Monad, and Stellar. Token availability varies by chain. For the full matrix, chain IDs, and token contract addresses, see Supported chains and tokens.In the sandbox, mint
rUSD test tokens to simulate collateral. See
Mint test tokens for collateral.What’s next
Access card details
Decrypt a virtual card’s PAN and CVC on the client so the cardholder can
start spending.
Test with simulations
Simulate card transactions and collateral funding in the sandbox.