Recover Funds - Base Documentation

Occasionally you need to move a balance out of a blocked account: a holder who lost their keys, or a balance you must reissue. Reclaim it with burnBlocked, then mint the same amount to the correct address. It’s gated by its own BURN_BLOCKED_ROLE and only works on an account that is already blocked.

Demo

The demo above is mock only. If you want to see onchain demos on Vibenet, head to Base chain demos.

New to B20? See the B20 Token Standard for the concepts and a full launch walkthrough. These samples target base-std@v1.0.0, viem@2.55.11, and Base Foundry v1.1.1.

Burn and Reissue the Blocked Balance

import { parseUnits, type Address } from "viem";
import { publicClient } from "../../shared/clients.js";
import { b20Abi } from "../abi.js";
import { sendContract } from "../write.js";

export async function recoverBlockedFunds(token: Address, blocked: Address, replacement: Address) {
  const amount = parseUnits("50", 6);
  await sendContract({ address: token, abi: b20Abi, functionName: "burnBlocked", args: [blocked, amount] });
  await sendContract({ address: token, abi: b20Abi, functionName: "mint", args: [replacement, amount] });
  const balance = await publicClient.readContract({ address: token, abi: b20Abi, functionName: "balanceOf", args: [replacement] });
  if (balance < amount) throw new Error("Replacement balance was not issued");
}

    function recoverStablecoin(address token, address blocked, address replacement) public {
        IB20(token).burnBlocked(blocked, 50e6);
        IB20(token).mint(replacement, 50e6);
        require(IB20(token).balanceOf(replacement) >= 50e6, "replacement not funded");
    }

base-cast send "$TOKEN_ADDRESS" "burnBlocked(address,uint256)" "$BLOCKED" 50000000 \
  --rpc-url "$RPC_URL" --private-key "$PRIVATE_KEY"
base-cast send "$TOKEN_ADDRESS" "mint(address,uint256)" "$REPLACEMENT" 50000000 \
  --rpc-url "$RPC_URL" --private-key "$PRIVATE_KEY"
base-cast call "$TOKEN_ADDRESS" "balanceOf(address)(uint256)" "$REPLACEMENT" --rpc-url "$RPC_URL"

See the B20 token standard for the complete interface, roles, and policies.

The blocked balance falls and the replacement address receives the same amount, leaving circulating supply unchanged.

burnBlocked requires BURN_BLOCKED_ROLE and only succeeds while the source is denied by TRANSFER_SENDER_POLICY.

See Also

Block an Account

Deny a specific address.

Reconcile with Memos

Match payments using onchain memos.