Polkadot Migration: What Developers Need to Know About the Relay Chain to Asset Hub Transition

What Is the Polkadot Migration?

The Polkadot migration refers to the transfer of core network functions—balances, staking, and governance—from the Relay Chain to the Asset Hub system parachain. This was executed on Kusama on October 7, 2025, and on Polkadot on November 4, 2025. The Asset Hub is a specialized parachain designed to manage user-facing operations, while the Relay Chain now focuses solely on consensus, security, and cross-chain interoperability.

This architectural change reduces state bloat on the Relay Chain, enables faster runtime upgrades, and prepares the network for the JAM (Join-Accumulate Machine) protocol. For developers, it means that certain RPC endpoints and runtime APIs have moved. Applications that previously queried the Relay Chain for balance, staking, or governance data must now target Asset Hub.

• Balances, staking, and governance migrated to Asset Hub.
• Relay Chain now handles only consensus and interoperability.
• Migration completed on November 4, 2025 for Polkadot.
• No action required for end users; developers must update RPC targets.

Technical Impact on RPC Endpoints

The most immediate impact for developers is the change in which chain handles specific RPC calls. Previously, queries like system.account, staking.*, and democracy.* were served by the Relay Chain. After migration, these calls must be directed to the Asset Hub's RPC endpoint.

For example, to get a user's DOT balance, you should now query the Asset Hub's system.account storage. Similarly, staking operations (bond, nominate, etc.) and governance proposals are now processed on Asset Hub. The Relay Chain's RPC will still work for consensus-related queries (e.g., chain.getBlock, chain.getHeader) and parachain information.

If you are using Substrate API Sidecar or similar tools, ensure you are pointing to the correct chain for each endpoint. OnFinality provides separate RPC endpoints for Polkadot Relay Chain and Polkadot Asset Hub, making it easy to route requests appropriately.

What Developers Need to Update

To ensure your dApps and services continue to function correctly after the migration, review the following areas:

1. **RPC Endpoint Configuration**: Update your application to use Asset Hub RPC endpoints for balance, staking, and governance queries. If you use a provider like OnFinality, you can switch to the Asset Hub-specific endpoint or use a unified gateway that routes requests appropriately.

2. **Runtime API Calls**: Any code that calls runtime APIs related to balances, staking, or governance should be updated to target Asset Hub. This includes custom scripts, bots, and monitoring tools.

3. **Testing**: Run a full test suite against Asset Hub's RPC to verify that all expected data is returned correctly. Pay special attention to edge cases like multisig accounts, proxy accounts, and vesting schedules.

4. **Infrastructure**: If you run your own nodes, ensure you are syncing both the Relay Chain and Asset Hub. For production, consider using a managed provider to avoid synchronization issues.

• Update RPC endpoints to Asset Hub for balance, staking, governance.
• Review and update runtime API calls in your codebase.
• Test thoroughly against Asset Hub testnet or mainnet.
• Ensure your node infrastructure syncs both chains.

Migration and Ledger Hardware Wallets

For users with Ledger hardware wallets, the migration also involves moving from legacy parachain-specific apps to the new Polkadot Generic app. This is a separate process from the Asset Hub migration but equally important. The Polkadot Migration app and the Polkadot Migration Assistant (by Zondax) help users transfer assets from old Kusama and parachain accounts to new Generic accounts.

Developers building wallet integrations should ensure their software supports the new Polkadot Generic app and the migration process. This includes updating account derivation paths and signing logic. The migration does not affect DOT held directly on the Relay Chain via the old Polkadot app—only assets on parachains using legacy apps need migration.

• Legacy parachain Ledger apps are deprecated; use Polkadot Generic app.
• Polkadot Migration app assists in transferring assets to Generic accounts.
• DOT on Relay Chain via old Polkadot app does not require migration.
• Wallet developers must support new Generic app derivation paths.

Testing and Validation Best Practices

Before deploying changes to production, follow these steps to validate your application's compatibility with the post-migration Polkadot network:

1. **Use a Testnet**: Polkadot's testnet (Westend) and Asset Hub testnet are available for testing. OnFinality provides RPC endpoints for both. Simulate balance transfers, staking operations, and governance votes to confirm correct behavior.

2. **Monitor RPC Responses**: Compare responses from Relay Chain and Asset Hub for the same queries. Ensure that data consistency is maintained and that no fields are missing.

3. **Check Documentation**: Refer to the official Polkadot Asset Hub migration FAQ and developer guides for any additional changes to runtime APIs or storage items.

4. **Engage with Community**: Join the Asset Hub Migration Support Telegram channel or Polkadot Forum to stay updated on any post-migration issues or patches.

• Test on Westend testnet before mainnet.
• Compare RPC responses between Relay Chain and Asset Hub.
• Review official migration documentation for API changes.
• Join community channels for real-time support.

How OnFinality Supports Your Migration

OnFinality offers a robust infrastructure platform that simplifies the transition. Our Polkadot RPC API provides dedicated endpoints for both the Relay Chain and Asset Hub, allowing you to route requests with minimal configuration changes. We also support dedicated nodes for teams that require guaranteed performance and custom configurations.

Our network coverage includes Polkadot, Asset Hub, and all major parachains, ensuring you have access to the data you need. Whether you are testing migration scenarios or running production applications, OnFinality's infrastructure is designed for reliability and ease of use.

For developers looking to migrate their RPC calls, our documentation provides clear examples and best practices. Visit our Polkadot network page to get started.

• Separate RPC endpoints for Relay Chain and Asset Hub.
• Dedicated node options for production workloads.
• Comprehensive documentation and support.
• Over 50 networks supported, including all Polkadot parachains.

Frequently Asked Questions