ERC-3643 and ERC-1400 are the two leading token standards for compliant security tokens, and they take different approaches. ERC-3643 is built around on-chain identity: it checks a verified identity registry on every transfer, so eligibility is enforced automatically. ERC-1400 is a broader framework for security tokens - partitioned balances, transfer rules with reason codes, and document handling - that is more flexible but less prescriptive about identity. Both are ERC-20-compatible. The right one depends on how you want compliance enforced.

What each standard is

ERC-3643 (often called T-REX) is a complete, opinionated standard for permissioned tokens. It pairs the token with an on-chain identity system and compliance rules, so only verified identities can hold it, enforced at the contract level.

ERC-1400 is a family of standards defining how a security token should behave - partitions (tranches), controlled transfers with transfer restriction reason codes, and document references. It specifies the behavior but leaves more of the compliance implementation to you.

The lineage helps explain the difference. ERC-1400 grew out of Polymath's early security-token work and is really a bundle: ERC-1410 for partitioned (tranche) balances, ERC-1594 for core transfers with a canTransfer pre-check that returns a reason code, ERC-1643 for attaching legal documents, and ERC-1644 for a controller that can force transfers. ERC-3643 came from the Tokeny/T-REX ecosystem and leans on ONCHAINID for the identity layer, which is why it feels like a complete product rather than a toolkit.

The core difference

The clearest distinction is identity. ERC-3643 makes verified on-chain identity central - transfers check an identity registry, so compliance is baked in and standardized. ERC-1400 focuses on the token's structure and transfer-control mechanics, leaving how you verify and track eligibility more open.

In short: ERC-3643 is identity-first and prescriptive; ERC-1400 is structure-first and flexible. ERC-3643 is also a finalized, published standard with a sizeable live footprint - billions of dollars of tokenized assets have been issued on T-REX implementations - which matters when you want battle-tested code rather than a bespoke build.

Strengths of each

ERC-3643's strength is turnkey compliance: the identity and rules framework is defined, interoperable, and widely used for regulated tokens, which reduces what you build and audit. It suits issuers who want a proven, standardized compliance path.

ERC-1400's strength is flexibility: partitions let you represent different share classes or lock-up tranches in one token, and the framework adapts to varied structures. It suits complex offerings that need that expressiveness.

How to choose

Match the standard to your needs. If you want standardized, identity-based compliance with less custom work, ERC-3643 is often the pragmatic choice - and its ecosystem is mature. If your deal needs multiple partitions, share classes, or bespoke transfer logic, ERC-1400's flexibility may fit better.

One feature both camps grapple with is the controller, or forced-transfer, power - ERC-1644 in the ERC-1400 family, and a comparable agent role in ERC-3643. It exists for good reasons: recovering tokens from a holder who has lost their keys, or complying with a court order to seize or reassign a security. But it is also exactly the centralization that auditors and sophisticated investors flag, because the same power that recovers lost keys can move anyone's tokens. The honest answer is to keep it, since regulated securities genuinely need it, but gate it behind a multisig and timelock and disclose it plainly.

Many real deals blend ideas from both, and some platforms implement one or the other for you. Whichever you pick, it must be audited and match your legal structure. If token standards are new to you, start with what a token standard is.

Where to go next

• Next: whitelisting and transfer restrictions in code.
• The basics: what a token standard is.
• Glossary: ERC-3643.

Sources: token-standard specifications (EIPs); rwa.xyz, as of 2026.