Circle's cirBTC is live. Read what changes in wrapped Bitcoin.

Circle launched cirBTC on June 8 with real-time Chainlink reserves. The fight with WBTC and cbBTC is about the trust model, not the backing.

The Editors · 6 min read · Jun 15, 2026

Circle's cirBTC is live. Read what changes in wrapped Bitcoin.

Circle launched cirBTC on Ethereum mainnet on June 8, 2026, an institutional-only ERC-20 backed 1:1 by Bitcoin in segregated custody, with real-time reserve attestation via Chainlink. It is the fourth credible US-regulated wrapped BTC in the market, behind WBTC, cbBTC, and tBTC. Every credible wrapper is 1:1, so backing is settled. What differs is the trust model around it.

Read this if you want to know what cirBTC actually does that the others do not, where the differentiation matters, and where it is marketing.

What cirBTC is, in one paragraph

cirBTC is an ERC-20 token issued by Circle, redeemable by KYB-verified institutions through Circle Mint. The mint flow takes native BTC into Circle custody and issues cirBTC at one-to-one. Redemption reverses that. Retail buyers cannot mint or redeem directly; they trade cirBTC on DEX and CEX venues once market makers seed liquidity. Reserve attestation runs through Chainlink Proof of Reserve, which reads custodian balances onchain and updates the attestation when reserves change, instead of a monthly cycle from an accounting firm.

The wrapped BTC market it walked into

The wrapped BTC market is bigger and more crowded than a year ago.

WBTC, run by BitGo since 2019, still holds between 65% and 85% of the wrapped BTC supply by market cap, around $9 billion (Binance Research via Bitget; Cryptonews coverage of the cirBTC launch). The two readings use different denominators; either way WBTC is the incumbent.
cbBTC, Coinbase's wrapper, sits between $2 billion and $5.9 billion in supply across Ethereum, Base, Solana and Arbitrum depending on the source (DefiLlama range as reported by Eco; Yahoo Finance figure on the cirBTC launch). That gap matters: $2B vs $5.9B is the difference between cbBTC as a clear number two and cbBTC closing on WBTC.
tBTC, Threshold Network's decentralized wrap, runs about $500 million (Eco research). It is the only wrap with permissionless redemption from any holder back to native BTC via a distributed signer set.

Behind those three sit FBTC and a long tail of bridged variants on individual L2s. Ethereum L2 TVL crossed $40 billion in May 2026 (L2Beat data cited in OAK Research), and most of that DeFi growth treats BTC as collateral, so the wrapper that sits closest to the protocols collecting that collateral wins the float.

Where cirBTC differs

Three things separate cirBTC from its US-regulated peers. Two of them matter.

Real-time on-chain attestation

WBTC publishes a reserve dashboard. cbBTC publishes attestations. cirBTC routes attestation through Chainlink oracles that read custodian wallets and update the contract automatically. If reserves and supply diverge, applications consuming the feed can pause minting on their side (Chainlink documentation on automated circuit breakers).

This matters most for protocols that mint stablecoins or loans against wrapped BTC. They can wire a circuit breaker into their own smart contract and stop fresh issuance the moment the attestation drops. It does not matter for a retail holder swapping cirBTC for ETH on Uniswap, who is reading the same DEX price as everyone else.

Compliance brand sits with the issuer

WBTC's biggest story in 2024 was the Justin Sun-linked custody expansion, which pushed MakerDAO to debate dropping it as collateral. cbBTC inherits Coinbase's compliance brand. cirBTC inherits Circle's. For institutions whose risk teams already approved USDC under the new stablecoin rules, the marginal review to approve cirBTC is small. That is the moat. It is also the ceiling: it does nothing for protocols that wanted WBTC out for being centralized in the first place.

Mint is institutional-only

What gets marketed as a feature is closer to a constraint. cirBTC mint and redemption is restricted to KYB-verified institutions. There is no retail redemption right. In normal conditions that is fine, because authorized participants arb the secondary price back to one. Under stress, when the secondary price decouples and arbs lose appetite, retail cannot drive the price back themselves. WBTC and cbBTC carry the same structural risk; tBTC does not.

What is unverified

A few things were not published before launch and matter for the call to use cirBTC as collateral.

Fees. Circle has not disclosed mint and redeem fees. The USDC analogue is fee-free above Circle Mint thresholds with bank costs separate, but that is not a guarantee.
Redemption windows. Same gap. WBTC and cbBTC publish theirs.
Arc readiness. Circle announced cirBTC for Ethereum and its own L1, Arc. Arc is not the trading venue on day one; Ethereum is.

Until these get filled in, treat headline parity claims with the same skepticism you would treat a stablecoin pegging itself off-chain.

What to watch over the next 90 days

If you want to know whether cirBTC is taking share from WBTC or building a new buyer base, watch three numbers:

cirBTC supply growth on Ethereum, tracked on DefiLlama. A slow build below $200M means the institutional pipeline is real but small. A vertical curve means a single fund parked size; do not project that line.
WBTC and cbBTC supply trend in the same window. Net wrapped BTC supply rising while cirBTC grows tells you Circle pulled new BTC into DeFi. Supply rotating from one wrapper to another tells you nothing changed; the same float moved.
DeFi protocol integrations. Aave, Morpho, MakerDAO governance threads. Whether protocols list cirBTC as collateral, at what loan-to-value, and whether they wire the Chainlink PoR feed into a circuit breaker is the test of whether the on-chain attestation pitch is a real product or a logo on a slide.

If you size institutional crypto stories, this is the one to keep open in a tab. Stablecoins were the first US-regulated crypto product category that mattered. Wrapped BTC is the second, and it is just becoming a real fight.

Sources

This is not financial advice.