Solana Reduces Block Time to 350 Milliseconds in First-Ever Slot-Time Cut

Solana speeds up transactions with first block-time reduction

Solana has activated a major upgrade on its main network, reducing the time it takes to produce new blocks from 400 milliseconds to 350 milliseconds. This is the first time Solana has shortened its block production time since the network launched. The change aims to make transactions confirm faster for users.

The upgrade, called SIMD-0525, went live on August 21, 2026, at a specific point in the network’s schedule known as slot 440,208,000 during epoch 1019. A slot is a fixed period during which a validator (a computer that helps run the network) can produce a block. By making slots shorter, Solana hopes to process transactions more quickly.

This change is part of a larger plan to eventually reduce block times to 200 milliseconds, but the network will proceed carefully, one step at a time.

How the upgrade works

• Solana’s block time has been reduced from 400ms to 350ms, the first such change since the network started.
• The upgrade is designed to give users faster transaction confirmations.
• Solana plans to reduce block time further to 200ms in stages: 350ms → 300ms → 250ms → 200ms.
• Each reduction will only happen if the network remains stable, with low rates of missed blocks.
• The number of slots in an epoch (a fixed period in Solana’s schedule) remains the same, but epochs will now complete faster.

What the Solana Foundation says

Jacob Creech, vice president of technology at the Solana Foundation, confirmed the upgrade and said the next target is 300 milliseconds. The foundation stated that the network will pause further reductions if too many blocks are skipped, which could indicate instability.

Improvements in how validators communicate and process blocks made this upgrade possible. However, Solana’s official documentation still lists the default slot duration as 400 milliseconds, even though the new 350-millisecond feature is now active.

What is confirmed

• The 350-millisecond slot time is now active on Solana’s mainnet.
• The upgrade was activated at slot 440,208,000 during epoch 1019.
• This is the first block-time reduction since Solana launched.
• The Solana Foundation plans further reductions to 200ms in stages, but only if the network remains stable.
• Jacob Creech of the Solana Foundation confirmed the change and the next target of 300ms.

What is still unclear

• The exact timeline for the next reduction to 300 milliseconds has not been announced.
• It is not yet known what indexing changes will be required to support the upgrade.
• The network’s stability after this change will determine whether further reductions proceed as planned.

Why faster block times matter

Block time is the average time it takes for a blockchain to create a new block of transactions. Shorter block times can lead to faster transaction confirmations, which may improve the experience for users and applications built on Solana. However, reducing block time too quickly could risk network stability, which is why Solana is proceeding in stages.

Sources

• The Defiant