Address Precompile

Address: 0x0000000000000000000000000000000000001004 The Sei Address precompile lets EVM applications interact directly with Sei’s address association system through standard smart contract calls. You can use it to query and create mappings between EVM addresses and their corresponding Cosmos addresses. You get cross-chain address management without a separate Cosmos SDK integration.

What is a precompile? A precompile is a special smart contract that the Sei protocol itself deploys at a fixed address. It exposes custom native chain logic to EVM-based applications. To the EVM, it behaves like a regular contract, but it executes privileged, low-level logic efficiently.

How does the Address precompile work?

The Address precompile at address 0x0000000000000000000000000000000000001004 exposes functions such as associate(), associatePubKey(), getSeiAddr(), and getEvmAddr().

EVM contracts and dApps can call address association functions directly, like any other smart contract method.
Operations run natively at the Cosmos SDK level for efficiency and security.
You do not need separate wallet integrations or complex cross-chain interactions.

Use cases

Cross-chain identity: Link EVM and Cosmos addresses for a unified user experience across both execution environments.
Address resolution: Build applications that can work with both EVM and Cosmos address formats.
Wallet integration: Let users associate their addresses once and then use both EVM and native Sei functionality.
DeFi applications: Create protocols that can interact with users regardless of their preferred address format.

What you’ll learn in this guide

After you finish this guide, you can:

Call association and lookup functions directly from your EVM contracts and dApps.
Handle signature verification and the signature format requirements for secure address association.
Query and validate address mappings between EVM and Cosmos formats.
Build cross-chain tools with unified address management for applications that span both execution environments.
Understand when and how address association happens automatically or manually.

Functions

The Address precompile exposes these functions:

Transaction functions

/// Associates an account given it's signature of any custom message.
/// @param v The v component of the signature.
/// @param r The r component of the signature.
/// @param s The s component of the signature.
/// @param customMessage A custom message that was signed by the address to be associated.
/// @return seiAddr The associated Sei address.
/// @return evmAddr The associated EVM address.
function associate(
    string memory v,
    string memory r,
    string memory s,
    string memory customMessage
) external returns (string memory seiAddr, address evmAddr);

/// Associates an account given it's compressed pubkey in hex format (excluding the '0x')
/// @param pubKeyHex The Hex-encoded compressed pubkey of the account to be associated, excluding the '0x'
/// @return seiAddr The associated Sei address.
/// @return evmAddr The associated EVM address.
function associatePubKey(
    string memory pubKeyHex
) external returns (string memory seiAddr, address evmAddr);

Query functions

/// Queries the corresponding Sei Address for some EVM address.
/// @param addr The EVM Address for which we want the corresponding Sei address.
/// @return response The corresponding Sei address.
function getSeiAddr(
    address addr
) external view returns (string memory response);

/// Queries the corresponding EVM Address for some Sei address.
/// @param addr The Sei Address for which we want the corresponding EVM address.
/// @return response The corresponding EVM address.
function getEvmAddr(
    string memory addr
) external view returns (address response);

Using the precompile

Setup

Prerequisites

Before you start, make sure that you have:

Node.js (v18 or higher)
The npm or yarn package manager
An EVM-compatible wallet
SEI tokens for gas
A Hardhat development environment set up

Install dependencies

Install the required packages to interact with Sei precompiles:

# Initiate a Hardhat 3 project (choose "Hardhat 3" and the Mocha + Ethers.js TypeScript setup)
npx hardhat --init

# Install ethers.js for smart contract interactions
npm install ethers

# Install @sei-js/precompiles for precompile addresses and ABIs
npm install @sei-js/precompiles@^3

Setup Hardhat environment

Create a hardhat.config.ts file with this content:

import { defineConfig, configVariable } from 'hardhat/config';
import hardhatToolboxMochaEthers from '@nomicfoundation/hardhat-toolbox-mocha-ethers';

export default defineConfig({
  solidity: '0.8.28',
  networks: {
    sei: {
      type: 'http',
      chainId: 1329,
      url: 'https://evm-rpc.sei-apis.com',
      accounts: [configVariable('PRIVATE_KEY')]
    }
  },
  plugins: [hardhatToolboxMochaEthers]
});

Store your private key in Hardhat’s encrypted keystore, so that you do not need a plaintext .env file:

npx hardhat keystore set PRIVATE_KEY

Import precompile components

JavaScript
Solidity

// Import Address precompile address and ABI
// View the entire ABI here: https://github.com/sei-protocol/sei-chain/tree/main/precompiles/addr
import { ADDRESS_PRECOMPILE_ABI, ADDRESS_PRECOMPILE_ADDRESS } from '@sei-js/precompiles';
import { ethers } from 'ethers';

// SPDX-License-Identifier: MIT
pragma solidity ^0.8.0;

interface IAddrPrecompile {
function associate(
string memory v,
string memory r,
string memory s,
string memory customMessage
) external returns (string memory seiAddr, address evmAddr);

function associatePubKey(
string memory pubKeyHex
) external returns (string memory seiAddr, address evmAddr);

function getSeiAddr(address addr) external view returns (string memory response);

function getEvmAddr(string memory addr) external view returns (address response);

}

Precompile address: The Address precompile is deployed at 0x0000000000000000000000000000000000001004.

Contract initialization

JavaScript
Solidity

Set up your provider, signer, and contract instance:

// Using EVM-compatible wallet as the signer and provider
const provider = new ethers.BrowserProvider(window.ethereum);
await provider.send('eth_requestAccounts', []);
const signer = await provider.getSigner();

// Create a contract instance for the addr precompile
const addr = new ethers.Contract(ADDRESS_PRECOMPILE_ADDRESS, ADDRESS_PRECOMPILE_ABI, signer);

// Initialize the contract instance in your Solidity code
contract CrossChainAddressManager {
  IAddrPrecompile constant ADDR = IAddrPrecompile(0x0000000000000000000000000000000000001004);
}

When does association happen?

In most cases, the association between EVM and Cosmos addresses happens automatically:

Method	Trigger	Requirements
Automatic	First transaction broadcast	Wallet signs any transaction
Manual (Signature)	associate() function	Custom message signature
Manual (PubKey)	associatePubKey() function	Compressed public key

How association works

Automatic association:

The association happens when a wallet first signs and broadcasts any transaction on Sei.
Most users do not need to take any other steps.
The association is permanent after it is created.

Manual association:

Use associate() for signature-based association.
Use associatePubKey() for public-key-based association.
Manual association is useful for advanced applications, or when automatic association has not happened.

Address format requirements

EVM addresses:

Standard Ethereum format: 0x1234... (20 bytes, 40 hex characters)
Case-insensitive, but typically lowercase

Sei addresses:

Cosmos format, with the sei1... prefix for regular addresses
Validator addresses use the seivaloper1... prefix
Bech32 encoding format

Step-by-step guide: Using the Address precompile

Associate address with signature

JavaScript
Solidity

// Associate addresses using a custom message signature
const message = `Associate my addresses - ${Date.now()}`;

try {
  // Get signature from user's wallet
  const signature = await signer.signMessage(message);
  const sig = ethers.Signature.from(signature);

  // Reconstruct the EIP-191 prefixed message that signMessage() actually signed:
  // "\x19Ethereum Signed Message:\n" + message length + message
  const customMessage = `\x19Ethereum Signed Message:\n${message.length}${message}`;

  // Convert signature components to strings
  const v = (sig.v - 27).toString();
  const r = sig.r;
  const s = sig.s;

  // Call associate function
  const tx = await addr.associate(v, r, s, customMessage);
  const receipt = await tx.wait();

  console.log('Association successful:', receipt);
} catch (error) {
  console.error('Association failed:', error);
}

contract AddressManager {
    IAddrPrecompile constant ADDR = IAddrPrecompile(0x0000000000000000000000000000000000001004);

    event AddressAssociated(address indexed evmAddr, string seiAddr);

    function associateMyAddress(
        string memory v,
        string memory r,
        string memory s,
        string memory customMessage
    ) external {
        (string memory seiAddr, address evmAddr) = ADDR.associate(v, r, s, customMessage);

        // Verify the association is for the caller
        require(evmAddr == msg.sender, "Association mismatch");

        emit AddressAssociated(evmAddr, seiAddr);
    }
}

Associate address with public key

JavaScript
Solidity

// Associate addresses using a public key
try {
  // Create or get a wallet's public key
  const wallet = ethers.Wallet.createRandom();
  const pubKeyWithout0x = wallet.signingKey.compressedPublicKey.slice(2);

  // Call associatePubKey function
  const tx = await addr.associatePubKey(pubKeyWithout0x);
  const receipt = await tx.wait();

  console.log('Public key association successful:', receipt);
} catch (error) {
  console.error('Public key association failed:', error);
}

contract AddressManager {
    IAddrPrecompile constant ADDR = IAddrPrecompile(0x0000000000000000000000000000000000001004);

    event AddressAssociated(address indexed evmAddr, string seiAddr);

    function associateWithPubKey(string memory pubKeyHex) external {
        (string memory seiAddr, address evmAddr) = ADDR.associatePubKey(pubKeyHex);

        // Store or emit the association
        emit AddressAssociated(evmAddr, seiAddr);
    }
}

Query Sei address from EVM address

JavaScript
Solidity

// Query the Sei address for a given EVM address
const evmAddress = '0x1234567890123456789012345678901234567890';

try {
  const seiAddress = await addr.getSeiAddr(evmAddress);
  console.log('Corresponding Sei address:', seiAddress);
} catch (error) {
  if (error.message.includes('not found') || error.message.includes('no association')) {
    console.log('No association found for this EVM address');
  } else {
    console.error('Error querying Sei address:', error);
  }
}

contract AddressManager {
    IAddrPrecompile constant ADDR = IAddrPrecompile(0x0000000000000000000000000000000000001004);

    function getUserSeiAddress(address evmAddr) external view returns (string memory) {
        return ADDR.getSeiAddr(evmAddr);
    }

    // Safe version with error handling
    function tryGetUserSeiAddress(address evmAddr) external view returns (bool success, string memory seiAddr) {
        try ADDR.getSeiAddr(evmAddr) returns (string memory result) {
            return (true, result);
        } catch {
            return (false, "");
        }
    }
}

Query EVM address from Sei address

JavaScript
Solidity

// Query the EVM address for a given Sei address
const seiAddress = 'sei1qqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqq6s8dpw';

try {
  const evmAddress = await addr.getEvmAddr(seiAddress);
  console.log('Corresponding EVM address:', evmAddress);
} catch (error) {
  if (error.message.includes('not found') || error.message.includes('no association')) {
    console.log('No association found for this Sei address');
  } else {
    console.error('Error querying EVM address:', error);
  }
}

contract AddressManager {
    IAddrPrecompile constant ADDR = IAddrPrecompile(0x0000000000000000000000000000000000001004);

    function getEvmFromSei(string memory seiAddr) external view returns (address) {
        return ADDR.getEvmAddr(seiAddr);
    }

    // Safe version with error handling
    function tryGetEvmFromSei(string memory seiAddr) external view returns (bool success, address evmAddr) {
        try ADDR.getEvmAddr(seiAddr) returns (address result) {
            return (true, result);
        } catch {
            return (false, address(0));
        }
    }
}

Complete integration example

JavaScript
Solidity

import { ADDRESS_PRECOMPILE_ABI, ADDRESS_PRECOMPILE_ADDRESS } from '@sei-js/precompiles';
import { ethers } from 'ethers';

async function addrExample() {
  // Setup
  const provider = new ethers.BrowserProvider(window.ethereum);
  await provider.send('eth_requestAccounts', []);
  const signer = await provider.getSigner();
  const addr = new ethers.Contract(ADDRESS_PRECOMPILE_ADDRESS, ADDRESS_PRECOMPILE_ABI, signer);

  const evmAddress = await signer.getAddress();

  try {
    // 1. Check if current EVM address has an associated Sei address
    console.log('=== Checking Current Association ===');
    try {
      const associatedSei = await addr.getSeiAddr(evmAddress);
      console.log('EVM address:', evmAddress);
      console.log('Associated Sei address:', associatedSei);

      // Verify reverse lookup
      const reverseEvm = await addr.getEvmAddr(associatedSei);
      console.log('Reverse lookup EVM address:', reverseEvm);
    } catch (error) {
      if (error.message.includes('not found') || error.message.includes('no association')) {
        console.log('No association found. You may need to make a transaction first or associate manually.');

        // 2. Demonstrate manual association with public key
        console.log('=== Creating Manual Association ===');
        const wallet = ethers.Wallet.createRandom();
        const pubKeyWithout0x = wallet.signingKey.compressedPublicKey.slice(2);

        const associateTx = await addr.associatePubKey(pubKeyWithout0x);
        const receipt = await associateTx.wait();
        console.log('Manual association completed:', receipt.transactionHash);
      } else {
        throw error;
      }
    }

    // 3. Demonstrate address resolution for different formats
    console.log('=== Address Resolution Examples ===');

    // Test with known Sei address format
    const testSeiAddr = 'sei1qqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqq6s8dpw';
    try {
      const correspondingEvm = await addr.getEvmAddr(testSeiAddr);
      console.log('Test Sei address:', testSeiAddr);
      console.log('Corresponding EVM address:', correspondingEvm);
    } catch (error) {
      console.log('Test address not associated:', testSeiAddr);
    }
  } catch (error) {
    console.error('Operation failed:', error);
  }
}

Contract example

// SPDX-License-Identifier: MIT
pragma solidity ^0.8.0;

interface IAddrPrecompile {
    function associate(
        string memory v,
        string memory r,
        string memory s,
        string memory customMessage
    ) external returns (string memory seiAddr, address evmAddr);

    function associatePubKey(
        string memory pubKeyHex
    ) external returns (string memory seiAddr, address evmAddr);

    function getSeiAddr(address addr) external view returns (string memory response);

    function getEvmAddr(string memory addr) external view returns (address response);
}

contract CrossChainAddressManager {
    IAddrPrecompile constant ADDR = IAddrPrecompile(0x0000000000000000000000000000000000001004);

    struct UserProfile {
        address evmAddress;
        string seiAddress;
        bool isVerified;
    }

    mapping(address => UserProfile) public userProfiles;
    mapping(string => address) public seiToEvm;

    event UserRegistered(address indexed evmAddr, string seiAddr);
    event AddressAssociated(address indexed evmAddr, string seiAddr);

    /**
     * @dev Register user with automatic address association lookup
     */
    function registerUser() external {
        address userEvm = msg.sender;

        // Try to get associated Sei address
        try ADDR.getSeiAddr(userEvm) returns (string memory seiAddr) {
            // Association exists
            userProfiles[userEvm] = UserProfile({
                evmAddress: userEvm,
                seiAddress: seiAddr,
                isVerified: true
            });

            seiToEvm[seiAddr] = userEvm;
            emit UserRegistered(userEvm, seiAddr);

        } catch {
            // No association found
            revert("Address not associated. Please associate your addresses first.");
        }
    }

    /**
     * @dev Batch query multiple EVM addresses
     */
    function batchGetSeiAddresses(
        address[] memory evmAddresses
    ) external view returns (string[] memory seiAddresses) {
        seiAddresses = new string[](evmAddresses.length);

        for (uint256 i = 0; i < evmAddresses.length; i++) {
            try ADDR.getSeiAddr(evmAddresses[i]) returns (string memory seiAddr) {
                seiAddresses[i] = seiAddr;
            } catch {
                seiAddresses[i] = ""; // Empty string if not associated
            }
        }
    }

    /**
     * @dev Check if an address pair is associated
     */
    function areAddressesAssociated(
        address evmAddr,
        string memory seiAddr
    ) external view returns (bool) {
        try ADDR.getSeiAddr(evmAddr) returns (string memory result) {
            return keccak256(bytes(result)) == keccak256(bytes(seiAddr));
        } catch {
            return false;
        }
    }
}

Client integration exampleDeploy the contract:

import { network } from 'hardhat';

// Hardhat 3 exposes ethers through a network connection rather than a global import
const { ethers } = await network.create();

async function main() {
  // The signer comes from the network config (encrypted keystore)
  const [deployer] = await ethers.getSigners();
  console.log('Deploying contracts with the account:', deployer.address);

  const balance = await deployer.provider.getBalance(deployer.address);
  console.log('Account balance:', ethers.formatEther(balance));

  const AddressManager = await ethers.getContractFactory('CrossChainAddressManager');
  console.log('Deploying AddressManager...', AddressManager);
  const addressManager = await AddressManager.deploy({
    gasLimit: 5000000n // Set a reasonable gas limit
  });
  await addressManager.waitForDeployment();

  console.log('AddressManager deployed to:', await addressManager.getAddress());
}

main().catch((error) => {
  console.error(error);
  process.exitCode = 1;
});

Then run:

npx hardhat run scripts/deploy.js --network sei

import { network } from 'hardhat';
// Path is relative to this file in scripts/ — Hardhat writes artifacts to the project root
import addressManagerAbi from '../artifacts/contracts/CrossChainAddressManager.sol/CrossChainAddressManager.json' with { type: 'json' };

// Hardhat 3 exposes ethers through a network connection rather than a global import
const { ethers } = await network.create();

async function main() {
  // The signer comes from the network config (encrypted keystore)
  const [deployer] = await ethers.getSigners();
  console.log('Interacting with the account:', deployer.address);

  const balance = await deployer.provider.getBalance(deployer.address);
  console.log('Account balance:', ethers.formatEther(balance));

  const addressManagerAddress = '0xYourAddressManagerContractAddress'; // Replace with your deployed contract address
  const addressManager = new ethers.Contract(addressManagerAddress, addressManagerAbi.abi, deployer);
  console.log('AddressManager deployed to:', await addressManager.getAddress());

  // Register user (requires existing address association)
  try {
    const registerTx = await addressManager.registerUser();
    await registerTx.wait();
    console.log('User registered successfully');

    // Get user's profile
    const userProfile = await addressManager.userProfiles(deployer.address);
    console.log('User profile:', userProfile);
  } catch (error) {
    console.error('Registration failed:', error);
  }
}

main().catch((error) => {
  console.error(error);
  process.exitCode = 1;
});

Then run the interaction script:

npx hardhat run scripts/interact.js --network sei

Security considerations & risks

Association permanence

Permanent mapping: After addresses are associated, the mapping cannot be changed or removed.
Single association: Each address can be associated with only one counterpart.
Verification: Always verify associations before you depend on them in critical operations.

Signature security

Custom messages: Use unique, timestamped messages to prevent replay attacks.
Message format: Follow the exact Ethereum Signed Message format for compatibility.

Troubleshooting

Common issues and solutions

// Set appropriate gas limits for different operations
const associateTx = await addr.associate(v, r, s, customMessage, {
  gasLimit: 200000 // Association operations
});

const pubKeyTx = await addr.associatePubKey(pubKeyHex, {
  gasLimit: 150000 // Public key association
});

Error code reference

Error	Cause	Solution
`invalid signature`	Malformed v, r, s components	Verify the signature parsing and format
`already associated`	The address already has an association	Check the existing association instead
`not found`	No association exists	Create an association first
`invalid public key`	Malformed public key format	Use the compressed format without the 0x prefix
`invalid address format`	Wrong address format	Use the correct EVM (0x…) or Sei (sei1…) format

Important notes

Address associations are permanent and cannot be changed after they are created.

Address formats

EVM addresses: Use the standard Ethereum format with the 0x prefix.
Sei addresses: Use the Cosmos format with the sei1 prefix for regular addresses.
Case sensitivity: EVM addresses are case-insensitive. Sei addresses are case-sensitive.

Association timing

Automatic: For most users, association happens automatically on their first transaction.
Manual: Use the precompile functions for programmatic association, or when automatic association has not happened.
Verification: Always verify that associations exist before you depend on them.

Signature requirements

Message format: For the associate() function, the message must include the Ethereum Signed Message prefix.
Component format: v, r, and s must be correctly formatted hex strings.
Replay protection: Use unique messages to prevent signature replay attacks.

Gas considerations

Association operations: Use a gas limit of approximately 200,000.
Query operations: These use the standard gas for a view function.
Batch operations: Scale gas limits based on the array size.

View the Address precompile source code and contract ABI.

​How does the Address precompile work?

​Use cases

​What you’ll learn in this guide

​Functions

​Transaction functions

​Query functions

​Using the precompile

​Setup

​Prerequisites

​Install dependencies

​Setup Hardhat environment

​Import precompile components

​Contract initialization

​When does association happen?

​How association works

​Address format requirements

​Step-by-step guide: Using the Address precompile

​Associate address with signature

​Associate address with public key

​Query Sei address from EVM address

​Query EVM address from Sei address

​Complete integration example

​Security considerations & risks

​Association permanence

​Signature security

​Troubleshooting

​Common issues and solutions

​Gas-related issues

​Error code reference

​Important notes

​Address formats

​Association timing

​Signature requirements

​Gas considerations

How does the Address precompile work?

Use cases

What you’ll learn in this guide

Functions

Transaction functions

Query functions

Using the precompile

Setup

Prerequisites

Install dependencies

Setup Hardhat environment

Import precompile components

Contract initialization

When does association happen?

How association works

Address format requirements

Step-by-step guide: Using the Address precompile

Associate address with signature

Associate address with public key

Query Sei address from EVM address

Query EVM address from Sei address

Complete integration example

Security considerations & risks

Association permanence

Signature security

Troubleshooting

Common issues and solutions

Gas-related issues

Error code reference

Important notes

Address formats

Association timing

Signature requirements

Gas considerations