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B20 is Base’s native token standard, introduced with the Beryl upgrade (Base mainnet activation June 25, 2026). It is an ERC-20 superset implemented as a native precompile rather than a smart contract: it keeps full ERC-20 compatibility while building roles, transfer policies, supply caps, pausing, memos, and permit directly into the chain. You create a B20 token by calling the singleton B20 factory precompile — there is no token contract to write, deploy, or audit.

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B20 vs. ERC-20

ERC-20B20
ImplementationSmart contract you write and deployNative precompile
CreationDeploy your own bytecodeOne createB20 call to the factory
Compliance featuresBuild them yourselfRoles, transfer policies, freeze-and-seize, pause, supply cap, and memos built in
Compatibility—Full ERC-20 selector parity — a drop-in for wallets, explorers, and indexers
Cost and throughputStandard EVM executionCheaper and higher-throughput (native)
Because B20 implements the full ERC-20 surface, existing wallets, explorers, and indexers treat a B20 token like any other ERC-20.

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How B20 works

All B20 tokens are created through the singleton B20 factory precompile. A single call configures and creates the token in one transaction: 
createB20(variant, salt, params, initCalls)
  • variant — ASSET or STABLECOIN.
  • salt — caller-chosen entropy that fixes the token’s deterministic address.
  • params — ABI-encoded name, symbol, initial admin, and decimals.
  • initCalls — an optional batch of configuration calls (grant roles, set the supply cap, bind policies) applied atomically at creation.

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Precompile addresses

PrecompileAddress
B20 factory0xB20f000000000000000000000000000000000000
Policy registry0x8453000000000000000000000000000000000002
Activation registry0x8453000000000000000000000000000000000001
Token addresses are deterministic and encode the variant in the address itself: [10-byte B20 prefix][1-byte variant][9-byte hash of deployer and salt]. Tokens created by the factory start with 0xB200…; the factory itself is 0xB20f…. You can predict a token’s address before creating it with getB20Address(variant, deployer, salt).

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Variants

VariantDecimalsAdds
Asset6–18, set at creationRebase multiplier, on-chain announcements, batched issuance, extra metadata
Stablecoin6, fixedImmutable ISO-style currency code (for example, USD)

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Built-in features

B20 ships a compliance and operations toolkit that an ERC-20 leaves you to build:
  • Role-based access control — DEFAULT_ADMIN_ROLE, MINT_ROLE, BURN_ROLE, BURN_BLOCKED_ROLE, PAUSE_ROLE, UNPAUSE_ROLE, and METADATA_ROLE. The Asset variant adds OPERATOR_ROLE. A token can be made permanently admin-less.
  • Transfer policies — each token binds allowlist or blocklist policies from the policy registry to per-actor scopes (transfer sender, transfer receiver, mint receiver).
    Every policy scope defaults to ALWAYS_ALLOW at creation. An unconfigured B20 is fully open — constrain it intentionally in initCalls.
  • Freeze-and-seize — burnBlocked burns from a policy-blocked account, the path regulated issuers need.
  • Supply cap — an optional cap enforced on every mint.
  • Granular pause — pause TRANSFER, MINT, or BURN independently, with separate pause and unpause roles.
  • Memos — attach a bytes32 reference (a payment ID or settlement tag) to transfers, mints, and burns. Each is emitted as a Memo event for off-chain reconciliation.
  • ERC-2612 permit and ERC-7572 contractURI are built in.

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Availability

B20 ships with the Beryl upgrade:
NetworkBeryl activation
Base SepoliaJune 18, 2026
Base mainnetJune 25, 2026, 18:00 UTC
Chainstack Base nodes serve the B20 precompiles, so you can create and query B20 tokens through your Chainstack Base endpoint.

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Use B20 on Chainstack

1

Deploy a Base node

Deploy a Base node on Chainstack and copy your endpoint.
2

Create a token

Call the B20 factory from a script or directly with cast. See the Deploy a B20 token tutorial for the full walkthrough.

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See also

Last modified on June 19, 2026