B20 token standard

Build with Base-native B20 tokens: ERC-20 compatible precompile tokens with roles, policy scopes, memos, supply caps, pausing, and variants.

B20 is Base’s native token standard: an ERC-20 superset implemented as Rust precompiles. Standard ERC-20 calls such as transfer, transferFrom, approve, balanceOf, and allowance work unchanged, so existing wallets, indexers, and app integrations can treat a B20 token like an ERC-20 token.

B20 adds issuer-grade controls at the chain level: policy-gated transfers and mints, role-based administration, granular pausing, supply caps, memos, ERC-2612 permit, and variant-specific features for assets and stablecoins.

Choose your path

Launch a token

Create a B20 token with the factory and mint the first supply.

Understand policies

Learn how token policy scopes point to PolicyRegistry entries.

Variants

Variant	Decimals	Address byte	Use when
Asset	6-18, configured at creation	0x00	You need asset features such as scaled balances, announcements, batch minting, or extra metadata.
Stablecoin	Fixed 6	0x01	You need a fixed-decimal token with a self-declared currency code.

Learn the model

• Architecture & precompiles: why B20 is configured through fixed precompile surfaces instead of deployed bytecode.
• Policies & scopes: how token scopes point to registry policies and gate operations.
• Roles & access control: who can mint, pause, seize, change metadata, and renounce administration.
• Token lifecycle: how creation, initCalls, operation, and admin renunciation fit together.
• Variants: Asset vs Stablecoin: how to choose a token variant.