Transaction V1 Mainnet Activation
Solana (SOL) · Releases & Updates · Sep 15, 2026
Solana Transaction V1 (max tx size 4,096 bytes) activated on mainnet-beta at epoch 1035 on September 15, 2026.
Solana's Transaction V1 upgrade raises the maximum transaction size by 3.3x, from 1,232 to 4,096 bytes, enabling larger and more complex transactions on the network. Mainnet activation was rescheduled to epoch 1035 after ecosystem teams requested additional testing time, and Transaction V1 went live on mainnet-beta on September 15, 2026. This is a network-level Solana (SOL) protocol change affecting validators, developers and infrastructure providers. Category: Layer-1 protocol upgrade.