Polygon Slashes Transaction Finality to 5 Seconds with Heimdall v2 Upgrade

Polygon has rolled out Heimdall v2, a major upgrade that brings finality times on its proof-of-stake (PoS) chain down to just five seconds – a significant improvement from the previous 1–2 minutes. The upgrade marks a milestone on Polygon’s “gigagas roadmap” and strengthens the chain’s push into fast, low-cost payments and real-world asset (RWA) settlement.

The overhaul includes a rebuilt consensus client and upgraded infrastructure aimed at improving stability, speed, and compatibility with Ethereum’s upcoming changes.

Faster Finality, Stronger Guarantees

Heimdall v2 dramatically reduces the time it takes for a transaction to become irreversible — a crucial feature for financial applications. Institutions and users alike need confirmation that once a transaction is completed, it can’t be undone. Finality in ~5 seconds brings Polygon’s performance closer to mainstream fintech services like Venmo, but with the added benefits of decentralization and programmability.

Centralized exchanges can now process deposits and withdrawals on Polygon twelve times faster. Developers, meanwhile, get more predictable execution for payment apps and tokenized financial instruments. Faster finality also reduces the risk of chain reorganizations, which can cause issues in high-volume or sensitive use cases.

A Rebuilt Core for Modern Demands

The Heimdall v2 upgrade replaces Polygon’s original consensus engine based on Tendermint with CometBFT, a modern implementation designed for better performance and flexibility. This change, implemented via PIP-43, lays the groundwork for future upgrades like single-block instant finality and higher throughput.

PIP-44, another component of the upgrade, brings Heimdall up to date with the latest Cosmos SDK, removing years of technical debt and aligning the client with modern development standards. Polygon has officially deprecated the old Heimdall version with PIP-62 and fully migrated to the new system.

The upgrade positions Polygon to offer real-time transaction guarantees — a necessity for institutional-grade payment rails, tokenized T-bills, and other regulated RWA applications.