Migrating from ERC20 tokens to a project’s native mainnet token is a critical phase in the lifecycle of most blockchain projects. Before launching their own mainnet, many teams issue ERC20-compliant tokens on the Ethereum network for fundraising and early distribution. Once the mainnet goes live, these tokens must be securely and accurately mapped to the new chain.
This article explores the three most common and effective approaches for executing a smooth token migration—ensuring user funds are protected, address mapping is accurate, and old tokens are properly retired. We'll also cover key technical steps, real-world implementations from major projects like EOS, TRON, and Qtum, and best practices for secure transitions.
Key Steps in Mainnet Token Migration
Before diving into the migration methods, it's essential to understand the core tasks involved in any ERC20-to-mainnet transition:
- Collect ETH Address to Mainnet Address Mappings
Users must link their Ethereum wallet address (holding the ERC20 token) with their new mainnet address. This process must prevent fraud, such as impersonation or incorrect submissions. - Verify ERC20 Token Balances
The system needs to audit how many tokens each Ethereum address holds at a specific block height—often called the "snapshot" point. - Distribute Native Tokens on the Mainnet
Based on the verified data, corresponding amounts of the native token are sent to users’ mainnet addresses. - Retire or Destroy the Old ERC20 Tokens
To avoid double-spending and maintain scarcity, the original ERC20 tokens must be permanently removed from circulation.
👉 Discover how top platforms manage large-scale token migrations with precision and security.
Method 1: Address Mapping via Smart Contract
One of the most secure and decentralized ways to collect address mappings is through an Ethereum-based smart contract. Only users who control the private key of an Ethereum address can interact with the contract, ensuring authenticity.
A prime example is EOS, which used a dedicated crowdsale contract (0xd0a6e6c5...) during its migration:
function register(string key) {
assert(today() <= numberOfDays + 1);
assert(bytes(key).length <= 64);
keys[msg.sender] = key;
LogRegister(msg.sender, key);
}In this model:
- Users call the
register()function, submitting their public key (formatted in base58, compatible with EOS). - The contract logs the Ethereum address (
msg.sender) and associates it with the provided mainnet public key. - Since only someone with access to the private key can send this transaction, spoofing is nearly impossible.
For broader accessibility, projects should provide tools that:
- Help users generate valid mainnet keys,
- Validate submitted addresses,
- Allow users to confirm successful registration.
While technically robust, this method requires users to have some familiarity with blockchain interactions—making user education crucial.
Method 2: Exchange-Facilitated Migration (Simplified User Flow)
To reduce complexity for non-technical users, some projects partner with centralized exchanges to handle the migration automatically.
TRON (TRX) adopted this approach:
- Users were instructed to deposit their TRX ERC20 tokens into supported exchanges before a cutoff date.
- Exchanges handled the snapshot and distribution of native TRON (TRX) tokens post-mainnet launch.
- No manual claiming or key registration was required by end-users.
Advantages:
- Minimal user effort.
- Lower risk of user error (e.g., sending to invalid addresses).
- High participation rates due to simplicity.
Drawbacks:
- Users must trust third-party platforms.
- Requires pre-existing exchange accounts.
- Centralization risk during a critical phase.
This method prioritizes convenience over decentralization but proves highly effective for mass adoption.
👉 See how leading exchanges support seamless token migrations for millions of users.
Method 3: Dedicated Wallet Integration
Another user-friendly solution involves using a specialized wallet that supports both Ethereum and the new mainnet.
Qtum implemented this strategy:
- A compatible wallet allowed users to hold both ERC20-QTUM and native QTUM.
- Inside the wallet interface, users could initiate a one-click swap.
- The wallet validated addresses, communicated with the Ethereum network, and ensured correct mainnet issuance.
Benefits:
- Eliminates need for exchange deposits.
- Maintains self-custody throughout the process.
- Reduces technical barriers while preserving decentralization.
However, success depends on wallet compatibility and widespread user adoption of that specific tool.
How ERC20 Tokens Are Retired
After migration, retiring old tokens prevents confusion and double-spending. Projects use several strategies:
Option A: Built-in stop() Function (Pre-programmed Destruction)
Forward-thinking teams embed a stop() or halt() function in their ERC20 contract from day one. EOS used this model via the DSStop mixin:
contract DSStop is DSAuth, DSNote {
bool public stopped;
modifier stoppable {
assert(!stopped);
_;
}
function stop() auth note {
stopped = true;
}
}Once activated, transfers are disabled—effectively freezing all tokens. While not burned immediately, they become unusable.
Option B: Token Burn via Transfer to Zero or Contract Address
For contracts without built-in controls, teams deploy a burn mechanism:
- Users or the project transfer remaining ERC20 tokens to an unspendable address (like
0x0) or a designated burn contract. - These tokens are irretrievable, achieving economic destruction.
Examples include:
- YOYOW, which encouraged users to send tokens to a null address.
- TRON, which publicly announced burn addresses and published transaction records.
Transparent communication and verifiable on-chain activity build trust during this phase.
Frequently Asked Questions
Q: What happens if I miss the migration deadline?
A: If no action is taken by the cutoff date, your ERC20 tokens may become worthless. Always follow official announcements and act early.
Q: Can I still use my ERC20 tokens after mainnet launch?
A: Typically not. Most projects disable or deprecate the old token after migration. Continued trading could indicate a scam or forked version.
Q: Is it safe to submit my mainnet address via a contract?
A: Yes—if done through an audited, official contract. Never enter private keys anywhere. Only sign transactions from trusted sources.
Q: Why do projects use ERC20 tokens initially?
A: It allows quick deployment for fundraising (e.g., ICOs) without building infrastructure first. Ethereum provides immediate liquidity and exchange support.
Q: How do I know my new tokens arrived?
A: Use a block explorer for the new chain to search your mainnet address. Wallets supporting the token will also display balances automatically.
Q: Should I trust exchange-led migrations?
A: Major exchanges like OKX have strong security and track records. However, always withdraw funds to self-custody after migration if long-term holding.
Conclusion
Token migration is more than a technical upgrade—it's a pivotal moment that tests a project’s operational maturity and community trust. Whether using smart contracts, exchange partnerships, or dedicated wallets, the goal remains the same: secure, accurate, and user-friendly transition.
Projects that combine clear communication, robust mechanisms, and multiple access points tend to achieve higher success rates. As blockchain ecosystems evolve, these lessons continue to shape best practices for future mainnet launches.
👉 Stay ahead of upcoming mainnet migrations with real-time updates and expert insights.