> ## Documentation Index
> Fetch the complete documentation index at: https://base-a060aa97-docs-devrel-859-eth-getproof-historical-proof.mintlify.site/llms.txt
> Use this file to discover all available pages before exploring further.

# Mint Supply

> Issue new stablecoin supply on Base as reserves grow, gated by a minter role and an optional supply cap.

When fiat lands in reserves, mint matching supply. Minting is gated by `MINT_ROLE`, and an optional supply cap keeps circulation from exceeding your reserves.

<Note>
  New to B20? See the [B20 Token Standard](/specifications/b20) for the concepts and a full launch walkthrough. These samples target `base-std@1505323`, `viem@2.55.11`, and Base Foundry `v1.1.1`.
</Note>

## Mint and Verify Supply

<CodeGroup>
  ```typescript TypeScript lines wrap expandable highlight={8} theme={null}
  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 mintAndVerify(token: Address, holder: Address) {
    const amount = parseUnits("1000", 6);
    await sendContract({ address: token, abi: b20Abi, functionName: "mint", args: [holder, amount] });
    const balance = await publicClient.readContract({ address: token, abi: b20Abi, functionName: "balanceOf", args: [holder] });
    if (balance < amount) throw new Error("Minted balance was not recorded");
    return balance;
  }
  ```

  ```solidity Solidity lines wrap expandable highlight={1} theme={null}
      function mintStablecoin(address token, address holder) public {
          IB20(token).mint(holder, 1_000e6);
          require(IB20(token).balanceOf(holder) >= 1_000e6, "mint not recorded");
      }
  ```

  ```bash CLI lines wrap expandable highlight={1} theme={null}
  base-cast send "$TOKEN_ADDRESS" "mint(address,uint256)" "$HOLDER" 1000000000 \
    --rpc-url "$RPC_URL" --private-key "$PRIVATE_KEY"
  base-cast call "$TOKEN_ADDRESS" "balanceOf(address)(uint256)" "$HOLDER" --rpc-url "$RPC_URL"
  ```
</CodeGroup>

See the [B20 token standard](/specifications/b20) for the complete interface, roles, and policies.

<Check>
  The holder balance increases by `1,000,000,000` base units, or 1,000 MUSD.
</Check>

<Warning>
  The caller needs `MINT_ROLE`, the recipient must pass `MINT_RECEIVER_POLICY`, and the mint must remain under the supply cap.
</Warning>

## See Also

<CardGroup cols={2}>
  <Card title="Burn Supply" icon="fire" href="/build-on-base/issue-stablecoins/burn-supply">
    Remove tokens from supply.
  </Card>

  <Card title="Supply Cap (B20 Standard)" icon="book" href="/specifications/b20/reference/interfaces/ib20/supply-cap">
    Supply cap in the B20 standard.
  </Card>
</CardGroup>