USDC on Ethereum: contract, finality, fees and monitoring
USDC on Ethereum is the largest deployment of Circle's dollar token, holding 47.26 billion USDC (66.5% of all USDC) on 27 October 2026. Ethereum runs 12-second slots and finalises checkpoints once two-thirds of staked ETH votes, which Circle treats as about 65 blocks (15 to 19 minutes); fees are gas priced as a burned base fee plus a priority fee, and balances can be read with balanceOf at the 'finalized' block tag or through indexed APIs such as Etherscan's tokenbalance.
| Token | USDC |
| Chain | Ethereum |
| Issuer | Circle |
| Contract (ERC-20) | 0xA0b86991c6218b36c1d19D4a2e9Eb0cE3606eB48 source |
The token
- USDC is a digital dollar issued by Circle, and Circle publishes monthly attestation reports on USDC reserve holdings. source
- As of 27 October 2026, Circle's public supply API shows 47,264,025,641 USDC on Ethereum, 66.5% of the 71.11 billion USDC across all chains. source
- Circle publishes a monthly third-party assurance report on USDC reserves from a Big Four accounting firm, prepared under AICPA attestation standards, and discloses reserve holdings weekly. source
- Most of the USDC reserve is held in the Circle Reserve Fund (USDXX), an SEC-registered 2a-7 government money market fund managed by BlackRock; the remainder is held in cash, mostly at large banks. source
- Only holders of a Circle Mint account can redeem USDC directly with Circle, at 1 USD per 1 USDC less any applicable fees, after completing Circle's KYC. source
- Circle does not charge Circle Mint users to tokenize USD into USDC or to receive USDC, but does charge fees for sending USDC on chain out of a Circle Mint account. source
- Ethereum is CCTP domain 0 in Circle's Cross-Chain Transfer Protocol, which moves USDC between supported chains by burning on the source chain and minting on the destination. source
The chain: finality and fees
- Ethereum proof of stake divides time into 12-second slots and 32-slot epochs. source
- The first block of each epoch is a checkpoint; when a pair of checkpoints gets votes from at least two-thirds of staked ETH, the later one is justified and the earlier one is finalised. source
- Reverting a finalised Ethereum block would cost an attacker at least one-third of all staked ETH. source
- An Ethereum transaction fee is gas used multiplied by the base fee plus a priority fee; the base fee is burned when the block is created. source
- Each Ethereum block targets half the current gas limit and can grow to the full limit (twice the target). source
- Ethereum's default gas limit is 60 million, standardised by EIP-7935 in the Fusaka upgrade, which activated on 3 December 2025. source
- On 5 May 2026 Etherscan's gas tracker showed standard gas around 0.15 gwei; ethereum.org's illustration put an ERC-20 transfer at about US$0.076 at 0.5 gwei with ETH near US$2,350. source
- The Glamsterdam upgrade, which changes gas accounting for state creation and state access, was scheduled for the Sepolia testnet on 6 October 2026; the Ethereum Foundation's 17 September 2026 announcement set no date for Hoodi or mainnet. source
Issuer controls
- In Circle's EVM token design, the blacklister role can stop all transfers to or from an address, the pauser role can pause the whole contract (stopping all transfers, minting and burning), and the owner can reassign these roles. source
- The verified USDC implementation on Ethereum (FiatTokenV2_2) exposes blacklist, unBlacklist, isBlacklisted, pause, unpause and rescueERC20 functions, and emits Blacklisted, UnBlacklisted, Pause and Unpause events that anyone can read on chain. source
- Circle's USDC Terms (updated 15 October 2026) reserve the right to block USDC transfers to and from an on-chain address under its blocklisting policy, and to freeze USDC sent to or received from a blocked address. source
- Circle states it can be required to freeze USDC and surrender the associated US dollars if it receives a legal order from a valid government authority, and holders of affected USDC can lose the ability to redeem it. source
- Circle states that on-chain USDC transactions are irreversible and that it cannot reverse or recall a transaction once initiated. source
Monitoring float on this rail
- Circle Mint credits Ethereum USDC deposits after 12 confirmations, which Circle puts at around 3 minutes. source
- For CCTP standard transfers, Circle waits about 65 Ethereum blocks (around 15 to 19 minutes) for finality; fast transfers proceed after 2 confirmations (around 20 seconds). source
- Ethereum JSON-RPC defines 'safe' as the latest safe head block and 'finalized' as the latest finalised block, so a balance read at 'finalized' reflects only finalised blocks. source
- Circle lists 0xA0b86991c6218b36c1d19D4a2e9Eb0cE3606eB48 as the only mainnet USDC contract on Ethereum; match transfers against this address rather than the token name or symbol. source
Explorers
Reading balances by API
| Provider | What it does | Source |
|---|---|---|
| Etherscan API V2 tokenbalance | Returns the balance of one ERC-20 contract for one address per call (chainid=1, action=tokenbalance); loop over each treasury address. Ethereum mainnet is available on Etherscan's free tier. | source |
| Alchemy Portfolio API, token balances by wallet | Returns native and ERC-20 balances for each wallet and network combination in one request, across Ethereum, Solana and 30+ EVM chains. | source |
| Coinbase Developer Platform, list EVM token balances | GET /v2/evm/token-balances/ethereum/{address} returns ERC-20 and ETH balances for one address, 20 per page by default. | source |
| Ethereum JSON-RPC (eth_call balanceOf) | Any Ethereum node can return a USDC balance via eth_call to balanceOf; the block parameter accepts 'latest', 'safe' and 'finalized'. | source |
Custody options
| Provider | What it offers | Source |
|---|---|---|
| Coinbase Prime | Supports USDC deposits and withdrawals on the Ethereum network in the Prime trading wallet. | source |
Seeing USDC on Ethereum float in Polynopsis
Polynopsis reads USDC balances on Ethereum directly from your public wallet addresses and from read-only custody connections, and shows them next to your bank and payout partner balances in one live position.
Frequently asked questions
How many confirmations should we wait for on Ethereum?
Circle Mint credits USDC deposits on Ethereum after 12 confirmations, around 3 minutes. Full finality, which Circle uses for CCTP standard transfers, is about 65 blocks or 15 to 19 minutes, and can be read directly with the 'finalized' block tag.
How are Ethereum fees set?
Each transaction pays gas used multiplied by the base fee plus a priority fee, and the base fee is burned. Blocks target half the gas limit, which defaults to 60 million gas since Fusaka. On 5 May 2026 standard gas was around 0.15 gwei.
Can Circle freeze USDC in our Ethereum wallet?
Yes. The USDC contract has a blacklister role that can stop all transfers to or from an address and a pauser role that can pause the contract, and Circle's terms reserve the right to block addresses under its blocklisting policy. Blacklisted and UnBlacklisted events are public on chain.
Who can redeem USDC for dollars?
Only Circle Mint account holders, at 1 USD per USDC less any applicable fees, after Circle's KYC. Circle does not charge to mint or receive USDC in Circle Mint but does charge to send USDC on chain out of the account.
Other stablecoin rails
Sources
- USDC overview · Circle
- Stablecoin supply by chain (public API) · Circle
- Transparency and stability · Circle
- USDC Terms (last updated 15 October 2026) · Circle
- CCTP supported blockchains and domains · Circle
- USDC contract addresses · Circle
- Proof-of-stake (PoS) · ethereum.org
- Gas and fees: technical overview · ethereum.org
- Building on Ethereum in 2026: what has changed · ethereum.org
- Glamsterdam testnet announcement (17 September 2026) · Ethereum Foundation Blog
- Get ERC20-token account balance · Etherscan
- Token balances by wallet (Portfolio API) · Alchemy
- List EVM token balances · Coinbase Developer Platform
- JSON-RPC API · ethereum.org
- Multi-chain support on Prime · Coinbase
- stablecoin-evm token design · Circle (GitHub)
- USDC implementation contract FiatTokenV2_2 (verified source) · Blockscout
- USDC risk factors · Circle
- Circle Mint blockchain confirmations · Circle
- CCTP finality and block confirmations · Circle
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