The Solana Alpenglow upgrade will be activated on October 21, 2026, reducing finality from 12.8 seconds to 150 milliseconds

Solana ecosystem R&D company Anza announced that the Alpenglow mainnet test version will be activated on October 21, 2026, at 14:50 (UTC). After the upgrade is completed, transaction finality is expected to shorten from approximately 12.8 seconds to 150 milliseconds.

Alpenglow will replace the existing TowerBFT voting mechanism with Votor, allowing validators to not write every vote to the chain but instead confirm consensus through direct communication and summarizing into smaller records. The network is expected to maintain the existing system for about 18 minutes, switching to Votor after staking SOL reaches 82% of the validator set. Another component of Alpenglow, Rotor, will adjust the distribution method of new blocks among validators, but the activation date has not yet been announced. This upgrade only includes Votor, and Solana will temporarily focus on the replacement of the consensus mechanism.