Solana’s Alpenglow upgrade cuts finality to about 150ms

Solana users can keep their existing wallets and send transactions as before, while apps gain a way to treat payments as settled much sooner: the network has activated its Alpenglow upgrade. The Solana Foundation says the new consensus protocol targets finality in roughly 150 milliseconds, down from about 12.8 seconds under the previous system. For people paying or trading on Solana, the change could shorten the wait for an app or exchange to treat a transaction as settled.

What does Alpenglow change about a Solana transaction?

Alpenglow changes how validators agree on transactions and when a block is considered final. According to the Solana Foundation’s Alpenglow upgrade page, it went live on mainnet at the start of epoch 1064 on October 21, 2026, at about 13:36 UTC.

Under the former TowerBFT system, validators submitted their votes as blockchain transactions, and finality took about 12.8 seconds. With Alpenglow, validators send votes directly to each other and combine them into certificates, allowing a block to become final after one or two rounds of voting.

Finality is the point at which an application can treat a payment as settled and no longer reversible. CoinDesk reported on the mainnet activation and described the practical use: an exchange could credit a deposit sooner, or a merchant could confirm a stablecoin payment without waiting through the former settlement period.

Do users need to change wallets or pay more?

No action is needed for ordinary users. The Solana Foundation says signing, sending and approving transactions work as before, and the upgrade does not change transaction formats, fees or how applications execute transactions.

The 150-millisecond figure is a target, not a guarantee that every payment will appear settled that quickly. CoinDesk reported that the time an app takes to show finality also depends on how quickly its service receives the relevant information; network conditions and the service itself matter to the user’s wait.

Why might Solana activity charts look different?

Validator votes no longer appear as transactions in blocks, so dashboards that counted them may show lower transaction totals after the switch. That accounting change does not by itself mean users are making fewer payments or trades.

The distinction matters when comparing activity before and after activation: older totals could include validator votes, while post-upgrade totals exclude them. The Solana Foundation says developers and indexers that count or parse block transactions need to re-baseline those metrics; users who simply send transactions or use apps do not need to migrate.

Source material

• Solana Foundation’s Alpenglow upgrade page — solana.com
• reported on the mainnet activation — coindesk.com