# Immutable Targets Mid-2027 OP Stack Upgrade for Its Chain

By Simon Yoon

Canonical URL: https://www.tokenpost.com/news/technology/51153
Published: 2026-11-07T22:48:56.000Z
Updated: 2026-11-07T22:48:56.000Z
Section: Technology

> The move would cut block time from two seconds to one second. Transaction costs are expected to rise slightly, and block production will pause for several hours during migration.

Immutable is targeting the middle of 2027 to move Immutable Chain from a custom Geth fork to OP Stack, a change that would make it an Ethereum rollup and halve block time.

Under the planned design, Immutable Chain would use proof-based bridging and put data availability on Ethereum. Block time is expected to fall from two seconds to one second, while OP Stack would allow the chain to adopt security patches faster.

The migration is expected to carry accounts, balances, contracts and approvals over unchanged. In almost all cases, users and developers will not need to take action. Transaction costs are expected to rise slightly, and native withdrawals could take about seven days.

Block production will pause for several hours during the migration. Immutable is targeting the middle of 2027 for the move.