Solana activated its Transaction V1 format on mainnet, raising the maximum size of a single transaction from 1,232 bytes to 4,096 bytes. The upgrade went live at the start of epoch 1,035 on September 15 at about 01:20 UTC. It gives developers more space to include instructions, signatures, and other transaction data in one operation.
The change does not increase Solana’s transactions per second. Instead, it expands how much information one transaction can carry.
The Solana Foundation says the larger format can support workloads such as zero-knowledge proofs, large multisignature setups and some on-chain signature schemes that developers could not easily fit under the previous limit.
Solana’s old 1,232-byte ceiling came from early network design choices tied to packet-size limits. This restriction remained even after the network moved to QUIC for transaction traffic. Under the new design, V1 transactions can reach 4,096 bytes, or about 3.3 times the previous maximum.
https://x.com/SolanaFloor/status/2099674029850497119?s=20
The larger space can reduce the need to split complex actions across several transactions. Developers can place more instructions and signatures inside one atomic transaction. For example, the extra room can support company wallets that require several approvals, privacy tools that use large cryptographic proofs, and DeFi operations that need several steps to either succeed together or fail together.
Before the upgrade, developers often worked around the size limit by using several transactions or other methods to fit larger operations on-chain. Solana’s SIMD-0296 proposal said the old cap restricted use cases with large proof sizes and multiple signatures. The proposal set the new maximum at 4,096 bytes, while SIMD-0385 introduced the V1 transaction format.
Solana continues to support Legacy and V0 transactions, so applications do not have to switch immediately. However, developers who want the larger transaction capacity must use V1. Infrastructure services also need to recognize the new format.
RPC providers, indexers, wallets, explorers and analytics tools may fail to process V1 transactions correctly until they update their systems.
The upgrade narrows one technical gap between Solana and Ethereum. Solana previously imposed a fixed 1,232-byte transaction limit, while Ethereum does not use the same fixed byte ceiling. Ethereum instead controls transaction execution and data through gas rules. Following EIP-7825, Ethereum also enforces a protocol-level per-transaction gas cap of 16,777,216 gas.
As a result, the two networks still use different approaches. Solana now allows much larger transaction payloads than before but keeps a fixed 4,096-byte cap for V1 transactions. Ethereum can support larger data-heavy operations when they remain within gas rules and the transaction gas cap. Therefore, the Solana change gives developers more room than they had before, but it does not remove every structural difference between the networks.
Meanwhile, Solana has continued changing other network parameters. In August, the network reduced slot time from 400 milliseconds to 350 milliseconds, with plans for a further reduction to 200 milliseconds.
Transaction V1 remains separate from those speed changes because it focuses on how much data developers can place inside a single transaction rather than how quickly the network produces slots across the Solana network.
Also Read: How Does Real-World Asset Tokenization Work on Solana?