Tezos Completes 20th Protocol Upgrade, Cuts Block Time to 6 Seconds

Tallinn upgrade activation and scope

Tezos activated the Tallinn protocol upgrade on 24 January 2026 at 16:06:56 UTC on mainnet block #11,640,289. This upgrade is the network’s 20th protocol revision since launch in 2018 and uses the same on-chain voting process as earlier Tezos changes. Developers from Nomadic Labs, Trilitech, and Functori prepared the proposal, while bakers, the network’s validators, voted through the Tezos governance system. Tallinn continues Tezos’ self-amending design, where users adopt new protocol versions without hard forks or chain splits.

Block time reduction and finality

The Tallinn upgrade reduces Tezos layer 1 block time from 8 seconds to 6 seconds per block. Finality, the point where transactions become practically irreversible on layer 1, now arrives after two blocks, so in about 12 seconds instead of 16 seconds. This change lowers latency for applications and users, who now see confirmed transactions faster on the base chain. Tezos technical documents state that the new block time does not increase hardware requirements for bakers that validate blocks.

All-baker attestations and BLS signatures

Tallinn reshapes how bakers attest to blocks, which is the process where validators confirm and secure each new block. Once at least 50% of bakers use tz4 addresses, every baker will attest to every block instead of a selected subset. This design uses Boneh–Lynn–Shacham (BLS) cryptographic signatures, which aggregate hundreds of signatures into a single signature per block. The aggregated signatures reduce data size and processing overhead on nodes, which strengthens network security and makes consensus leaner than in previous protocol versions.

Address indexing and storage efficiency

The Tallinn upgrade introduces an Address Indexing Registry designed to compress how the protocol stores addresses on-chain. The new mechanism replaces repeated full addresses with references, so applications store short identifiers instead of entire address strings. Official Tezos communications describe storage efficiency gains of up to 100x for some Michelson applications, especially non-fungible token (NFT) ledgers and enterprise-scale smart contracts. This reduction in storage needs lowers the amount of address data written to the chain and reduces disk space usage for nodes that store the ledger.

Impact on layer 2 and broader context

Shorter layer 1 block times also affect Etherlink, the Tezos ecosystem’s Ethereum Virtual Machine (EVM) compatible layer 2 network. Etherlink publishes its data to Tezos layer 1, so 6-second blocks reduce the time required to secure layer 2 activity on the base chain. Official materials describe this as part of the Tezos X roadmap, which focuses on faster settlement and lower costs for applications built on Tezos. Tallinn fits this roadmap by combining base-layer performance changes, support for layer 2 scaling, and governance-driven upgrades within Tezos’ forkless, self-amending model.