Solana has published an analysis of the proposed Transaction V1 format, focusing on the trade-off between a larger transaction envelope and the removal of Address Lookup Tables, or ALTs. The Aug. 17 report links the work to proposed Solana Improvement Documents SIMD-0296 and SIMD-0385.
The proposal would increase the transaction envelope to 4,096 bytes while changing how referenced accounts are represented. The article is an analysis of a proposed format, not an announcement that all Solana transactions have already moved to V1.
Why ALT removal matters
Under the current v0 format, an address can be represented through a lookup-table index. The report says V1 would instead include referenced accounts in an inline address array, which can increase serialized size because each full public key uses 32 bytes.
Solana’s analysis says around 62% of observed v0 transactions in its sample referenced at least one ALT. It estimates that dense ALT transactions can add more than 1,500 bytes when represented in V1, though half of the sampled transactions showed less than 420 bytes of excess.
Capacity is not uniform
The report says the current workload appears broadly compatible with the 4,096-byte envelope, while noting that the unchanged 64-account limit can remain a constraint for account-heavy applications. It also describes potential validator benefits from making fee and resource requests available earlier in transaction metadata.
Wallets, SDKs, RPC providers and application teams would need serialization and transaction-building support if the proposal advances. The analysis should not be interpreted as a production activation notice.
