Polkadot Asset Hub Migration: A Developer's Guide to the Relay Chain Transition

What Is the Polkadot Asset Hub Migration?

The Polkadot Asset Hub migration is a major network upgrade that transfers core user-facing functionality—including balance management, staking, and governance—from the Relay Chain to the Asset Hub system parachain. This transition, part of the broader Plaza project, aims to reduce Relay Chain state bloat, enable faster and safer network upgrades, and pave the way for the JAM (Join-Accumulate Machine) architecture.

The migration occurred on November 4, 2025, for Polkadot (and earlier on October 7, 2025, for Kusama). It was executed seamlessly in the background, requiring no action from end users. Funds and staking positions were automatically moved to Asset Hub without any loss or interruption.

For developers, the key change is that operations previously targeting the Relay Chain—such as balance transfers, staking actions, and governance votes—now occur on Asset Hub. This means RPC endpoints and transaction construction must be updated accordingly.

• Balances, staking, and governance moved to Asset Hub.
• Relay Chain now focuses solely on consensus and interoperability.
• No user action required; automatic migration of funds and positions.
• Part of Polkadot's evolution toward JAM for modular scalability.

How the Migration Affects RPC Endpoints and dApp Development

The most immediate impact for developers is the need to update RPC endpoints. Previously, balance queries and transfer transactions were sent to the Relay Chain. Now, these must be directed to the Asset Hub parachain. The Asset Hub's chain ID and endpoint differ from the Relay Chain.

For example, to query a user's DOT balance, you must now call the `system.account` storage on Asset Hub instead of the Relay Chain. Similarly, staking operations (bond, nominate, withdraw) are now handled by Asset Hub's staking pallet, not the Relay Chain's.

Governance actions, including voting on referenda, also moved to Asset Hub. The governance pallets are now deployed on Asset Hub, so your dApp's governance features must target the correct chain.

Relay Chain RPC endpoints remain essential for consensus-related queries (e.g., validators, era info) and cross-chain messaging (XCMP). You will likely need to maintain connections to both chains.

• Update RPC endpoints: use Asset Hub for balances, transfers, staking, governance.
• Relay Chain endpoints still needed for consensus and XCMP.
• Transaction construction must target Asset Hub's chain ID.
• Test your dApp against Asset Hub testnet before deploying to mainnet.

Key Benefits for Developers and Users

The migration brings several improvements that enhance the developer and user experience on Polkadot:

Lower existential deposit: reduced from 1 DOT to 0.01 DOT, making accounts more accessible.

Significantly reduced transaction fees on Asset Hub compared to the Relay Chain.

Expanded asset support: Asset Hub natively supports stablecoins like USDT and USDC, as well as other ecosystem tokens.

Fee flexibility: users can pay transaction fees in any supported asset, not just DOT.

Direct access to trustless Ethereum bridges, enabling seamless cross-chain asset transfers.

For developers, these changes mean lower barriers for users and more flexible dApp designs. You can now build applications that allow fee payment in stablecoins, reducing user friction.

• Existential deposit reduced from 1 DOT to 0.01 DOT.
• Lower transaction fees on Asset Hub.
• Support for stablecoins and multi-asset fee payment.
• Direct Ethereum bridge access.
• Faster network upgrades due to reduced Relay Chain complexity.

Updating Your Infrastructure: Node and RPC Configuration

If you run your own node, you must ensure it is configured to sync both the Relay Chain and Asset Hub. The Asset Hub is a parachain, so your node needs to be set up as a full node for the Polkadot Relay Chain with parachain syncing enabled. Alternatively, you can run a dedicated Asset Hub node.

For those using RPC providers, verify that your provider offers dedicated endpoints for Asset Hub. OnFinality, for example, provides separate RPC endpoints for Polkadot Relay Chain and Polkadot Asset Hub, ensuring you can target the correct chain with minimal latency.

When constructing transactions, ensure you use the correct chain ID and spec version. The Asset Hub's chain ID is different from the Relay Chain's. Always check the latest chain specifications from official sources.

Consider implementing a fallback strategy: if your primary RPC endpoint fails, switch to a backup provider. OnFinality's multi-region infrastructure offers high availability for both Relay Chain and Asset Hub endpoints.

• Run a full Relay Chain node with parachain syncing or a dedicated Asset Hub node.
• Use separate RPC endpoints for Relay Chain and Asset Hub.
• Verify chain IDs and spec versions in your transaction construction.
• Implement RPC provider redundancy for high availability.

Testing and Validation: Asset Hub Testnet

Before deploying updates to mainnet, thoroughly test your dApp on the Polkadot Asset Hub testnet (also known as Westend Asset Hub). The testnet mirrors mainnet functionality and allows you to validate endpoint changes, transaction construction, and user flows without risking real funds.

Key test scenarios include: balance queries, DOT transfers, staking operations (bond, nominate, withdraw), governance voting, and fee payment with alternative assets. Ensure your dApp correctly handles errors from Asset Hub, such as insufficient balance or invalid nonce.

OnFinality provides RPC endpoints for Westend Asset Hub, enabling developers to test with realistic network conditions. Use these endpoints to simulate mainnet traffic and verify your application's resilience.

• Test on Westend Asset Hub (testnet) before mainnet deployment.
• Validate balance queries, transfers, staking, and governance flows.
• Test fee payment with USDT and other supported assets.
• Use OnFinality's testnet RPC endpoints for reliable testing.

Common Pitfalls and How to Avoid Them

Developers may encounter several issues when adapting to the migration. Here are common pitfalls and solutions:

Using Relay Chain endpoints for balance queries: This will return outdated or incorrect data. Always use Asset Hub endpoints for user balances.

Incorrect chain ID in transactions: Ensure your transaction construction uses Asset Hub's chain ID. Check the latest chain specifications.

Assuming staking operations remain on Relay Chain: Staking pallets have moved. Update your dApp's staking logic to target Asset Hub.

Ignoring fee changes: With lower fees and multi-asset fee payment, you may need to adjust fee estimation logic in your dApp.

Not updating governance integration: Governance actions now occur on Asset Hub. Update your governance UI and backend accordingly.

• Always use Asset Hub endpoints for user-facing operations.
• Verify chain IDs and spec versions regularly.
• Update staking and governance logic to target Asset Hub.
• Adjust fee estimation for lower fees and multi-asset support.

Conclusion: Embracing the Modular Future of Polkadot

The Polkadot Asset Hub migration marks a significant step toward a more modular, scalable, and user-friendly network. By offloading user-facing functions to a dedicated system parachain, the Relay Chain can focus on its core roles of consensus and interoperability, while Asset Hub provides a richer, more flexible experience for users and developers.

For developers, the migration requires updating RPC endpoints, transaction construction, and testing workflows. However, the benefits—lower fees, multi-asset support, and faster upgrades—make the effort worthwhile.

OnFinality is committed to supporting the Polkadot ecosystem with reliable, high-performance RPC infrastructure for both the Relay Chain and Asset Hub. Whether you need public endpoints or dedicated nodes, OnFinality provides the tools and reliability you need to build on Polkadot with confidence.

• Migration completed November 4, 2025, with no user action required.
• Developers must update RPC endpoints and transaction logic.
• Benefits include lower fees, multi-asset support, and faster upgrades.
• OnFinality offers reliable RPC endpoints for Polkadot Relay Chain and Asset Hub.

Frequently Asked Questions