Overview

The Bank precompile provides ERC20-style access to native Cosmos SDK tokens, enabling smart contracts to query balances and token supplies through standardized interfaces. It serves as a Solidity wrapper around the Cosmos SDK x/bank module.

Address: 0x0000000000000000000000000000000000000804

Related Module: x/bank

Primary Methods

balances

Signature: balances(address account) → Balance[] memory

Description: Queries all native token balances for a specific account address and returns an array of Balance (ERC-20 contract address & amount) structures.

import { ethers } from "ethers";

// Connect to the network
const provider = new ethers.JsonRpcProvider("<RPC_URL>");

// Precompile address and ABI
const precompileAddress = "0x0000000000000000000000000000000000000804";
const precompileAbi = [
  "function balances(address account) view returns (tuple(address contractAddress, uint256 amount)[])"
];

// Create a contract instance
const contract = new ethers.Contract(precompileAddress, precompileAbi, provider);

// Address to query
const accountAddress = "0xd8dA6BF26964aF9D7eEd9e03E53415D37aA96045"; // Placeholder

async function getBalances() {
  try {
    const balances = await contract.balances(accountAddress);
    console.log("Balances:", balances);
  } catch (error) {
    console.error("Error fetching balances:", error);
  }
}

getBalances();

Parameters:

  • account (address): The account address to query balances for

Returns: Array of Balance structures with contractAddress and amount fields

totalSupply

Signature: totalSupply() → Balance[] memory

Description: Queries the total supply of all native tokens in the system. Returns comprehensive supply information for every token registered in the system.

import { ethers } from "ethers";

// Connect to the network
const provider = new ethers.JsonRpcProvider("<RPC_URL>");

// Precompile address and ABI
const precompileAddress = "0x0000000000000000000000000000000000000804";
const precompileAbi = [
  "function totalSupply() view returns (tuple(address contractAddress, uint256 amount)[])"
];

// Create a contract instance
const contract = new ethers.Contract(precompileAddress, precompileAbi, provider);

async function getTotalSupply() {
  try {
    const supply = await contract.totalSupply();
    console.log("Total Supply:", supply);
  } catch (error) {
    console.error("Error fetching total supply:", error);
  }
}

getTotalSupply();

Parameters: None

Returns: Array of Balance structures showing total supply for each token

supplyOf

Signature: supplyOf(address erc20Address) → uint256

Description: Queries the total supply of a specific token by providing its ERC20 contract address. More efficient when you need supply information for a single token.

import { ethers } from "ethers";

// Connect to the network
const provider = new ethers.JsonRpcProvider("<RPC_URL>");

// Precompile address and ABI
const precompileAddress = "0x0000000000000000000000000000000000000804";
const precompileAbi = [
  "function supplyOf(address erc20Address) view returns (uint256)"
];

// Create a contract instance
const contract = new ethers.Contract(precompileAddress, precompileAbi, provider);

// ERC20 address to query
const erc20Address = "0xdAC17F958D2ee523a2206206994597C13D831ec7"; // Placeholder for a token contract

async function getSupplyOf() {
  try {
    const supply = await contract.supplyOf(erc20Address);
    console.log("Supply of", erc20Address, ":", supply.toString());
  } catch (error) {
    console.error("Error fetching supply:", error);
  }
}

getSupplyOf();

Parameters:

  • erc20Address (address): The ERC20 contract address of the token

Returns: Total supply of the specified token as uint256

Data Structures ->

Balance

The Balance struct represents a token balance with its associated ERC20 contract address:

  • contractAddress (address): The ERC20 contract address representing the native token
  • amount (uint256): Token amount in the smallest denomination

Full Interface & ABI

Bank Solidity Interface
// SPDX-License-Identifier: LGPL-3.0-only
pragma solidity >=0.8.18;

/// @dev The IBank contract's address.
address constant IBANK_PRECOMPILE_ADDRESS = 0x0000000000000000000000000000000000000804;

/// @dev The IBank contract's instance.
IBank constant IBANK_CONTRACT = IBank(IBANK_PRECOMPILE_ADDRESS);

/// @dev Balance specifies the ERC20 contract address and the amount of tokens.
struct Balance {
    /// contractAddress defines the ERC20 contract address.
    address contractAddress;
    /// amount of tokens
    uint256 amount;
}

/**
 * @author Evmos Team
 * @title Bank Interface
 * @dev Interface for querying balances and supply from the Bank module.
 */
interface IBank {
    /// @dev balances defines a method for retrieving all the native token balances
    /// for a given account.
    /// @param account the address of the account to query balances for.
    /// @return balances the array of native token balances.
    function balances(
        address account
    ) external view returns (Balance[] memory balances);

    /// @dev totalSupply defines a method for retrieving the total supply of all
    /// native tokens.
    /// @return totalSupply the supply as an array of native token balances
    function totalSupply() external view returns (Balance[] memory totalSupply);

    /// @dev supplyOf defines a method for retrieving the total supply of a particular native coin.
    /// @return totalSupply the supply as a uint256
    function supplyOf(
        address erc20Address
    ) external view returns (uint256 totalSupply);
}
Bank ABI
{
  "_format": "hh-sol-artifact-1",
  "contractName": "IBank",
  "sourceName": "solidity/precompiles/bank/IBank.sol",
  "abi": [
    {
      "inputs": [
        {
          "internalType": "address",
          "name": "account",
          "type": "address"
        }
      ],
      "name": "balances",
      "outputs": [
        {
          "components": [
            {
              "internalType": "address",
              "name": "contractAddress",
              "type": "address"
            },
            {
              "internalType": "uint256",
              "name": "amount",
              "type": "uint256"
            }
          ],
          "internalType": "struct Balance[]",
          "name": "balances",
          "type": "tuple[]"
        }
      ],
      "stateMutability": "view",
      "type": "function"
    },
    {
      "inputs": [
        {
          "internalType": "address",
          "name": "erc20Address",
          "type": "address"
        }
      ],
      "name": "supplyOf",
      "outputs": [
        {
          "internalType": "uint256",
          "name": "totalSupply",
          "type": "uint256"
        }
      ],
      "stateMutability": "view",
      "type": "function"
    },
    {
      "inputs": [],
      "name": "totalSupply",
      "outputs": [
        {
          "components": [
            {
              "internalType": "address",
              "name": "contractAddress",
              "type": "address"
            },
            {
              "internalType": "uint256",
              "name": "amount",
              "type": "uint256"
            }
          ],
          "internalType": "struct Balance[]",
          "name": "totalSupply",
          "type": "tuple[]"
        }
      ],
      "stateMutability": "view",
      "type": "function"
    }
  ],
  "bytecode": "0x",
  "deployedBytecode": "0x",
  "linkReferences": {},
  "deployedLinkReferences": {}
}