Question 1

Why was 4,096 bytes chosen as the new limit?

Accepted Answer

The SIMD-0296 authors picked 4,096 bytes so a transaction fits inside a single standard 4 KiB memory page on validator hardware, keeping per-transaction memory handling cheap without spanning multiple pages.

Question 2

When does Transaction V1 go live on Solana mainnet?

Accepted Answer

Anza scheduled mainnet activation for September 9, 2026, confirming the date on August 29. The format has run on testnet since epoch 1025 on September 1.

Question 3

What breaks if RPC providers and indexers do not prepare?

Accepted Answer

Calls omitting maxSupportedTransactionVersion: 1 return error -32015, blockSubscribe can stall on a null block, and indexers scanning for ComputeBudgetProgram instructions silently report zero fees; Anza requires upgrading to Agave v4.2.

Anza

Solana sizes its new 4,096-byte transaction limit to one memory page

One sharp brief.
Every day.

Anza

Solana sizes its new 4,096-byte transaction limit to one memory page

One sharp brief.Every day.

One sharp brief.
Every day.