USDC and the Circle Stablecoin, Measured Onchain

The Circle stablecoin, USDC, is a fiat-backed digital dollar issued by Circle Internet Financial. One USDC is designed to be redeemable for one US dollar held in reserve, and it moves across more than a dozen blockchains as a bearer token. The interesting part is not the dollar peg, which holds. It is that the same USDC dollar can appear two or three times in a naive supply count, once as the native issuance and again as bridged copies on other chains, which is why two careful totals can differ by tens of billions.

According to Allium's stablecoins dataset (Allium data, October 12, 2026), USDC's adjusted onchain circulating supply is $69.62B, second only to USDT at $190.00B. Together those two tokens account for $259.62B of the $311.75B adjusted total, or 83.3% of all onchain stablecoin supply.

Key takeaways

• USDC is a fiat-backed stablecoin issued by Circle, redeemable one-for-one for US dollars held in reserve, and the second-largest stablecoin by onchain supply (Allium data, October 12, 2026: $69.62B adjusted).
• The headline number depends on methodology. Raw onchain supply across all stablecoins is $336.44B, but the adjusted figure that nets out double-counted bridged copies is $311.75B.
• Bridged USDC is a claim on collateral locked elsewhere, not an independent dollar. Across the market, native supply is $282.33B and bridged supply is $29.42B.
• USDC is fiat-backed. Of the $311.75B adjusted market, $270.84B is fiat_backed, the dominant peg mechanism by a wide margin.
• A yield-bearing wrapper trading above $1.00 is not a depeg. sUSDS at $1.1127 drifts up by design, while USDC sits at $1.0000.

Why the Circle stablecoin sits at the center of onchain dollars

Stablecoins are the settlement asset for most onchain activity, and two issuers dominate it. USDC is the larger of the two fully US-regulated, fiat-backed options that most institutions reach for first, because its reserve model and public reporting are straightforward to reason about. Per Circle's own USDC page, each token is backed by cash and short-dated US Treasuries, with reserves held in segregated accounts and reported through Circle's transparency program.

That matters because the use cases have moved past trading. Payment companies now settle merchant and cross-border flows in stablecoins, treasuries park idle cash in them, and fintechs embed them as a dollar rail. When Visa builds tooling to help banks and merchants understand stablecoin movement, and when institutions model the future size of the stablecoin economy, the asset they are modeling is overwhelmingly USDT and USDC. Getting the USDC number right is therefore not a trivia question. It changes the denominator for every downstream estimate.

How USDC is issued, moved, and redeemed

The mechanics are deliberately simple, which is part of the appeal.

• Mint. An approved institutional customer wires US dollars to Circle. Circle issues an equal amount of USDC to that customer's blockchain address. Reserve goes up, supply goes up, one-for-one.
• Transfer. The customer sends USDC to anyone, on whichever supported chain they are using. The token is a bearer asset, so possession is control. No bank sits in the middle of the transfer itself.
• Bridge. To move USDC to another chain, a holder either locks native USDC and mints a bridged representation, or uses Circle's native cross-chain mechanism. Per Circle's Cross-Chain Transfer Protocol documentation, CCTP burns USDC on the source chain and mints native USDC on the destination chain, which avoids leaving a wrapped copy behind.
• Redeem. An institutional holder returns USDC to Circle and receives US dollars back. The returned USDC is burned, supply goes down, reserve goes down.

The bridge step is where the counting problem is born. A third-party lock-and-mint bridge leaves native USDC frozen in a contract while a bridged token circulates elsewhere. If a data pipeline counts both, it has counted the same dollar twice.

Two totals, one asset: the number that gets double-counted

This is the tension worth remembering. There is no single USDC supply you can read off a block explorer without choosing a methodology, and the two defensible methodologies produce different numbers.

The raw approach sums every token that reports itself as USDC on every chain. The adjusted approach identifies which of those are native issuance and which are bridged claims on collateral locked elsewhere, flags the bridged supply, and reports it separately so it is not silently stacked on top of native dollars. Across the whole stablecoin market the gap between those two methods is the difference between $336.44B raw and $311.75B adjusted.

The adjusted figure does not subtract bridged supply. It includes it, flagged, so a reader can see both the independent native dollars and the dependent bridged claims without conflating them. Market-wide that split is $282.33B native against $29.42B bridged.

Allium data, October 12, 2026. Raw versus adjusted is the single most common source of inflated crosschain totals.

Where USDC sits against the rest of the market

USDC is fiat-backed, and fiat backing dominates onchain dollars. Of the $311.75B adjusted market, $270.84B is fiat_backed. Crypto-backed designs account for $15.87B, stablecoin-backed $13.43B, hybrid $8.69B, and RWA-backed $2.42B. Algorithmic designs, the category that drew the most attention after past failures, are now $0.13B, roughly 0.04% of the market.

Allium data, October 12, 2026, adjusted onchain circulating supply.

USDC's distribution across chains follows the broader pattern. Ethereum holds $149.74B of stablecoin supply and Tron $95.07B, with Solana at $15.51B, BSC at $14.57B, Base at $5.26B, and Arbitrum at $4.25B. USDC is a meaningful presence on most of these, which is exactly why a crosschain view has to resolve the same dollar consistently from chain to chain.

What changes for a business that settles in USDC

The practical case for USDC is concrete, and it shows up as before-and-after differences in how money moves.

• Faster settlement. A cross-border payment that would sit in correspondent banking for one to two business days clears onchain in minutes, so working capital is not locked up waiting to settle.
• Weekend and holiday availability. USDC transfers do not stop on Saturdays or bank holidays, so a treasury can rebalance when it needs to rather than when the wires reopen.
• Programmable rails. Because USDC is a token, a payout can be released by a smart contract on a condition rather than by a manual bank instruction, which removes a human step from recurring flows.
• Auditable movement. Every mint, transfer, and burn is on a public ledger, so reconciliation can read the chain directly instead of waiting for a counterparty statement.

For a deeper look at where this adoption is moving fastest, see our write-up on B2B stablecoin payments.

Reading USDC consistently across every chain it lives on

To state a single USDC figure you can defend, each onchain record has to resolve to the same fields regardless of which chain it came from: the asset, the issuer, the sender, the recipient, the amount, the USD value, the transaction type, and critically whether that token is native issuance or a bridged representation. A mint on Ethereum, a CCTP transfer to Base, and a lock-and-mint copy on a third chain all look different at the raw log level, and a bridged copy that is silently added to native supply is the exact mechanism that inflates a crosschain total.

Allium normalizes those records across 150+ chains, applies an is_native flag so bridged supply is identified and reported separately rather than stacked on native dollars, and standardizes each transfer into a common schema. That is what lets the $311.75B adjusted figure be stated alongside the $336.44B raw figure as two measurements of the same market rather than a contradiction. The underlying tables are documented in Allium's stablecoin datasets. For the operational side of this, our note on crosschain stablecoin monitoring walks through what to track.

Risks and open questions

• Reserve and counterparty risk. USDC's peg depends on the quality and accessibility of its reserves. A fiat-backed stablecoin is only as sound as the assets behind it and the institutions holding them, which is why Circle's reserve composition and reporting are the thing to watch rather than the onchain price alone.
• Bridged supply fragility. Bridged USDC depends on the bridge contract and the locked collateral behind it. A bridge exploit can leave bridged tokens outstanding with no backing, which is a different failure mode from a reserve shortfall.
• Regulatory variation. Stablecoin rules differ by jurisdiction and are still settling in several of them. How USDC is treated for a given use case can depend on where the user and the counterparty sit.
• Counting discipline. Any total that mixes native and bridged supply without flagging the difference will overstate independent dollars. The question to ask of any USDC number is which methodology produced it.
• False depegs. A yield-bearing wrapper trading above par is not a broken peg. sUSDS at $1.1127 is drifting up by design, while USDC held $1.0000 in the same snapshot. Reading the two the same way produces a false alarm.

Frequently asked questions

What is the Circle stablecoin?

The Circle stablecoin is USDC, a fiat-backed digital dollar issued by Circle Internet Financial. Each USDC is designed to be redeemable for one US dollar held in reserve, backed by cash and short-dated US Treasuries per Circle's own disclosures, and it circulates as a bearer token across more than a dozen blockchains.

How large is USDC onchain?

USDC's adjusted onchain circulating supply is $69.62B (Allium data, October 12, 2026), making it the second-largest stablecoin after USDT at $190.00B. The two together account for 83.3% of the $311.75B adjusted onchain stablecoin market.

Why do USDC supply figures differ between sources?

Because of bridged tokens. A raw count sums every token reporting itself as USDC on every chain, including bridged copies. An adjusted count identifies which supply is native and which is a bridged claim on collateral locked elsewhere, and reports them separately. Market-wide the gap is $336.44B raw versus $311.75B adjusted.

What backs USDC?

USDC is fiat-backed. Per Circle's transparency reporting, reserves are held in cash and short-dated US Treasuries in segregated accounts. Fiat backing is the dominant model onchain: of the $311.75B adjusted stablecoin market, $270.84B is fiat_backed (Allium data, October 12, 2026).

Is USDC the same as USDT?

No. Both are large fiat-backed stablecoins, but they are issued by different companies under different reserve and reporting regimes, USDC by Circle and USDT by Tether. By onchain supply USDT is larger at $190.00B versus USDC at $69.62B (Allium data, October 12, 2026).

Does USDC trading above or below $1.00 mean it has depegged?

Not necessarily, and small deviations are normal. In the October 12, 2026 snapshot USDC held $1.0000. By contrast, a yield-bearing wrapper like sUSDS trading at $1.1127 is drifting above par by design and is not a depeg, so the two should not be read the same way.

Interested in learning more about Allium’s stablecoin data? Speak to someone on the team.

Allium provides onchain data infrastructure. Companies named in this article may be Allium customers, prospects or commercial counterparties. The authors and other Allium personnel may hold positions in the assets discussed. This article is informational only and is not investment, legal or tax advice. Data and information last reviewed: October 12, 2026.