ICRC-107: a standard for fee collection in ICRC ledgers

[bogwar]

Many ICRC-based ledgers (such as ckBTC) already implement partial fee collection, often charging fees for transfer transactions but not for approve transactions. However, there is currently no standardized way to:

1. Indicate and configure who should collect fees (or if fees are burned).
2. Record fee collection information on existing ledgers.
3. Provide clear semantics for wallets, explorers, and other integrations to interpret fee information.

ICRC-107 aims to address this gap by defining:

• A set of metadata entries that indicate how fees are collected.
• A minimal interface for setting and enabling fee collection.
• A backward-compatible standard for populating and understanding fee-collection fields in ICRC-3 blocks corresponding to ICRC-1 and ICRC-2 transactions.
• Guidance on how to interpret fee collection fields, as recorded in blocks, in a consistent way.