Fiat / issuer reservesRank #2

USDCUSD Coin

Circle

Market cap: $77.2B
Circulating supply: 77.2B
Networks: 15

Full USDC profile: ERC-20, permit, proxy patterns, cross-chain, flash loans, and compliance EIPs — with implementation notes and verified contract context.

Overview

Most developer-friendly and compliance-forward stablecoin. Native on 32 blockchains as of early 2026 with Cross-Chain Transfer Protocol (CCTP) for native burns-and-mints across 21 chains. Circle began trading on the NYSE under ticker CRCL on 5 June 2025; the IPO closed on 6 June 2025.

Supply by chain

Market cap

$77.2B

Circulating supply

77.2B

Supply chains

151

Chain	Supply	Market cap	Share
Ethereum	51.0B	$51.0B	66.0%
Solana	7.8B	$7.8B	10.1%
Hyperliquid L1	5.0B	$5.0B	6.5%
Base	4.3B	$4.3B	5.6%
Arbitrum	2.2B	$2.2B	2.9%
Polygon	1.8B	$1.8B	2.3%
BSC	1.3B	$1.3B	1.7%
Avalanche	558.8M	$559M	0.72%
Sui	387.4M	$387M	0.50%
StarkNet	311.6M	$312M	0.40%
Stellar	274.7M	$275M	0.36%
Monad	237.2M	$237M	0.31%
Other tracked chains (127)	2.1B	$2.1B	2.7%
Current circulating supply by chain from DeFiLlama. Small supply footprints are grouped after the top 12 chains and may include bridged or non-curated deployments.

Features

Engineering-oriented breakdown of capabilities: standards, who they matter for, integration rationale, per-feature risks, and vetted external references (specs, docs, verified source).

Primary Ethereum verified source: Etherscan

Feature	Standards	Audience	Why it matters	Risk / caveat	References
EIP-2612 permit() authorization	EIP-2612 ERC-20	User	Enables gasless approvals via signature — critical for one-tx flows in DeFi; wallet must support typed data signing.	Permit replay/nonce bugs in your app can drain allowances; pin domain separator and deadline handling.	EIP-2612 Circle: multi-chain USDC Verified FiatToken (Ethereum)
EIP-3009 transferWithAuthorization authorization	EIP-3009 ERC-20	User	Supports meta-transfers and payment APIs with ephemeral nonces — used for gas abstraction and commerce patterns.	Nonce reuse and signature replay are catastrophic; centralize nonce tracking per authorizer.	EIP-3009 Circle developer docs
Permit2 compatible authorization	Permit2 (Uniswap)	User	Lets protocols unify allowance management across tokens — reduces approval UX friction when combined with Permit2 router patterns.	Permit2 contract allowances are powerful; verify spender contracts and expiries.	Permit2 repo
CCTP v2 cross-chain cross chain	CCTP	Both	Burn/mint native USDC across domains without liquidity pools — preferred vs bridged USDC.e for new integrations.	Must use correct TokenMessenger/MessageTransmitter addresses per domain; wrong domain config bricks flows.	CCTP developer docs
Blacklist and Pause compliance	—	Corporate	FiatToken admin can freeze addresses or pause globally — custody and DeFi protocols must surface failures to users.	Regulatory and operational freezes are opaque to pure smart-contract logic; plan for sudden illiquidity.	Verified proxy (Ethereum)
TransparentUpgradeableProxy compliance	ERC-1967 proxy pattern	Corporate	Implementation can be upgraded — monitor implementation changes and diff bytecode on upgrades for breaking behavior.	Governance/compromise of admin can alter token logic; dependency risk for deep integrations.	EIP-1967 OpenZeppelin proxies
SEC-registered reserve fund compliance	—	Corporate	Reserve composition is disclosed for regulatory and institutional users — informs treasury policy, not on-chain settlement guarantees.	Off-chain fund and banking risk remains; not convertible 1:1 on-chain without issuer rails.	Circle USDC
Gasless meta-transactions authorization	EIP-3009 EIP-712	User	Relayers submit signed `transferWithAuthorization` — enables sponsored gas for end users when relayer is trusted.	Relayer compromise or bad fee logic can censor or reorder; users must verify domain separation.	EIP-712 EIP-3009

EIP / ERC support matrix

Standards & compliance support for USDC. Click an EIP to jump to the global deep-dive section.

Verified contract: 0xA0b8…eB48

Standard	Status	Notes
Core
ERC-20 Fungible token standard	Implemented	Foundation interface. Every EVM wallet, DEX, and DeFi protocol interacts with USDC via this interface.
Signatures & typed data
EIP-712 Typed structured data signing	Implemented	Prerequisite for all signature-based flows. Binds signatures to a specific contract address and chain ID — prevents signatures from being replayed on other chains or against other contracts.
EIP-2612 Permit — gasless ERC-20 approval	Implemented	Collapses the two-transaction approve + action DeFi flow into a single transaction. User signs off-chain, dApp or relayer submits permit() + the DeFi action in one call. Required for ERC-4337 paymaster flows and gasless onboarding.
EIP-3009 transferWithAuthorization	Implemented	Preferred over EIP-2612 for payment use cases: (1) atomic — the transfer happens in one call, no separate transferFrom needed; (2) random nonces allow concurrent payment authorizations from the same address; (3) validAfter/validBefore enables scheduled and time-bounded payments; (4) cancelAuthorization enables refund and reversal patterns.
EIP-1271 Signature validation for smart contracts	Implemented	Institutional flows where the USDC holder is a Safe or AA wallet can now use signature-based permit flows directly. Previously required Permit2 or EOA co-signer workarounds.
Upgradeability & proxies
EIP-1967 Standard proxy storage slots	Implemented	Allows Circle to patch bugs and add features without requiring a token migration. The EIP-1967 standard means block explorers, risk tools (Tenderly, Forta), and monitoring systems automatically detect the proxy and show the correct ABI.
EIP-1822 UUPS — universal upgradeable proxy	Not implemented	No behavioral impact for token users. Relevant for forks: if you deploy a USDC-compatible token using UUPS, the upgrade mechanism differs from Circle's production deployment.
Vaults & yield
ERC-4626 Tokenized yield vault standard	Not implemented	To build yield-bearing USDC products, integrate with Aave, Compound, or other ERC-4626 yield wrappers — do not expect deposit/withdraw/convertToAssets on the canonical USDC address.
Compliance
Freeze Address freezing / blacklisting	Implemented	Always check isBlacklisted() before building payment pipelines that depend on USDC. Blacklisting is immediate and affects both sending and receiving. Etherscan shows blacklist events — monitor for operational awareness.
Seize Fund seizure / clawback	Not implemented	Frozen USDC remains in totalSupply() and balanceOf() — supply tracking is unaffected by freezes. No surprise supply changes from seizure events.
Pause Global transfer pause	Implemented	DeFi protocols that hold USDC should account for the possibility of a global pause in their risk models. A pause would freeze all USDC-dependent operations including DEX swaps, lending, and collateral liquidations.
Cross-chain
ERC-7802 Crosschain token interface	Alternative	Via CCTP v2: Circle Cross-Chain Transfer Protocol — proprietary burn-and-mint with off-chain attestation. Achieves the same cross-chain fungibility goal as ERC-7802 through a different mechanism.
Flash Loans
ERC-3156 Flash loans	Not implemented	Use Aave or Balancer flash loan pools for single-transaction USDC borrowing.
Data sourced from verified Etherscan contract source code. Implementations may differ across networks — always verify on the specific chain you integrate with.

Technical notes

6 decimals.
FiatToken v2.2 uses bit-packing: single storage slot per address (bit 255 = blacklist, bits 0-254 = balance) — saves ~6-7% gas.
Five-role admin: admin (upgrades), owner (roles), masterMinter (mint allowances), pauser (global pause), blacklister (freeze), plus rescuer (rescueERC20 for stuck tokens).
EIP-1271 added in v2.2 — smart contract wallets can sign permits.
CCTP v2: fast finality (~20s ETH, ~8s L2), hooks for atomic post-transfer actions, TokenMessengerV2 + MessageTransmitterV2.
Critical: native USDC vs bridged USDC.e — always confirm native address per chain.

Reserves & peg

Reserves: Cash and Circle Reserve Fund (US Treasuries via BlackRock/BNY Mellon)
Collateral: Fiat and equivalents (off-chain)
Peg mechanism: Hard 1:1 — redeem via Circle Mint (institutional) or exchanges
Auditor: Deloitte (monthly attestation)

Ecosystem

DeFi integration: #1 or #2 liquidity on Aave, Compound, Curve, Uniswap, MakerDAO across all chains
Yield: None native; earnable via DeFi lending

Risk factors

mediumCentralizationlowBanking dependency — SVB depeg March 2023

Technical references

Issuer compliance docs

www.circle.com/en/legal/usdc-terms

Verified contract · Ethereum

FiatToken v2.2

0xA0b8…eB48· block 6,082,465

Block explorers

Ethereumprimary Solanaprimary Baseprimary Arbitrumprimary Polygonprimary Avalancheprimary Optimismprimary Sui Stellar Aptos NEAR Hedera ZKsync Era Starknet XRP Ledger

Networks & contracts

Deployments by chain — primary rows are highlighted. Always verify addresses against issuer docs before mainnet integrations.

Network	Standard	Contract	Explorer
EthereumPrimary	ERC-20	`0xA0b86991c6218b36c1d19D4a2e9Eb0cE3606eB48` FiatToken v2.2	View
SolanaPrimary	SPL	`EPjFWdd5AufqSSqeM2qN1xzybapC8G4wEGGkZwyTDt1v`	View
BasePrimary	ERC-20	`0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913` Native, not bridged	View
ArbitrumPrimary	ERC-20	`0xaf88d065e77c8cC2239327C5EDb3A432268e5831` Native USDC, not USDC.e	View
PolygonPrimary	ERC-20	`0x3c499c542cEF5E3811e1192ce70d8cC03d5c3359` Native (0x2791 is bridged)	View
AvalanchePrimary	ERC-20	`0xB97EF9Ef8734C71904D8002F8b6Bc66Dd9c48a6E`	View
OptimismPrimary	ERC-20	`0x0b2C639c533813f4Aa9D7837CAf62653d097Ff85`	View
SuiSecondary	RegulatedCoin	`0xdba34672e30cb065b1f93e3ab55318768fd6fef66c15942c9f7cb846e2f900e7::usdc::USDC` Circle mainnet coin type (suiscan)	View
StellarSecondary	Stellar asset	`USDC:GA5ZSEJYB37JRC5AVCIA5MOP4RHTM335X2KGX3IHOJAPP5RE34K4KZVN` Circle-issued USDC on Stellar (stellar.expert)	View
AptosSecondary	Fungible asset	`0xbae207659db88bea0cbead6da0ed00aac12edcdda169e591cd41c94180b46f3b` Circle mainnet fungible asset (explorer.aptoslabs.com)	View
NEARSecondary	NEP-141	`17208628f84f5d6ad33f0da3bbbeb27ffcb398eac501a31bd6ad2011e36133a1` Native USDC token ID on NEAR (nearblocks.io)	View
HederaSecondary	HTS	`0.0.456858`	View
ZKsync EraSecondary	ERC-20	`0x1d17CBcF0D6D143135aE902365D2E5e2A16538D4`	View
StarknetSecondary	ERC-20	`0x033068F6539f8e6e6b131e6B2B814e6c34A5224bC66947c47DaB9dFeE93b35fb` Circle mainnet deployment (Voyager)	View
XRP LedgerSecondary	IOU	`5553444300000000000000000000000000000000.rGm7WCVp9gb4jZHWTEtGUr4dd74z2XuWhE` Circle native USDC on XRPL (livenet.xrpl.org)	View

Engineering deep dive

Integration notes

Always distinguish native USDC from legacy USDC.e bridged variants per chain—addresses differ and integrations break silently. Prefer CCTP for cross-chain movement when you need native mint semantics.

Developer UX

permit and transferWithAuthorization unlock gasless and one-shot payment flows; ensure your relayer or wallet stack supports the same EIP stack you deploy on.