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.

Recent Upgrades Show Focus on Payments

Earlier this month, Polygon implemented a hard fork dubbed Bhilai, increasing the chain’s throughput to over 1,000 transactions per second. The fork also introduced support for Ethereum’s upcoming Pectra upgrade and EIP-7702, which enables smart accounts and more flexible interactions.

Combined, these upgrades suggest Polygon is focused on becoming the blockchain of choice for high-throughput, payment-heavy applications. The chain now handles over $1 billion in payment volume in the first half of 2025 and supports a stablecoin supply of $2.7 billion — one of the highest among L1 and L2 chains.

What’s Next for Polygon

Polygon PoS is set to join the Agglayer by the end of the year. This move aims to unify liquidity and improve interoperability across chains in the Polygon ecosystem. Single-block instant finality is also on the roadmap, which could cut finality times even further while maintaining decentralization.

With Heimdall v2 live, Polygon is laying the technical groundwork to scale beyond crypto-native users, and potentially become the backend for global financial infrastructure.

Date	Event
Feb 2024	AggLayer launched; Napoli upgrade on PoS
June 2024	1 billion POL Grants Program initiated
Aug–Sep 2024	Token swap MATIC → POL; exchanges implement support
Nov–Dec 2024	Plonky3 proven fastest ZK; support for ERC‑7683; ISO 27001 certification
Dec 2024	WSPN stablecoin partnership with Polygon (WUSD)
Jan 2025	Jio Platforms partnership to bring Web3 to 450M+ users in India