# Circle's cirBTC Supply Reaches 4,300 Tokens Backed by 4,448 Bitcoin

By John Kim

Canonical URL: https://www.tokenpost.com/news/business/24283
Published: 2026-09-25T22:44:13.000Z
Updated: 2026-09-25T22:44:13.000Z
Section: Business

> Reserves exceed circulating cirBTC by about 147.518 BTC. Supply is split between the Arc and Ethereum networks, with most of it on Arc.

Circle's cirBTC wrapped Bitcoin token has a total supply of 4,300.67531386 across the Arc and Ethereum networks, with 4,448.19333037 Bitcoin (BTC) held in reserve.

Reserves exceed cirBTC supply by approximately 147.518 BTC on a one-to-one backing basis. Each cirBTC is backed one-to-one by native BTC.

Most of the supply sits on Arc, which holds 3,577.5618468 cirBTC. Ethereum accounts for the remaining 723.11346706 cirBTC.

## How cirBTC works

Circle launched cirBTC on Ethereum on June 8, 2026. The token is designed to let native Bitcoin be used in smart-contract applications such as lending, borrowing, trading and settlement, without the holder selling the underlying BTC.

Eligible institutional customers can mint and redeem cirBTC through Circle Mint. They can also use the token as collateral to obtain USDC liquidity.

Circle International Bermuda Limited issues the token. The underlying BTC is held exclusively for the benefit of cirBTC holders and is segregated from Circle's corporate assets.

## Custody and reserve checks

Custody is provided through Circle National Trust, the trade name of First National Digital Currency Bank, N.A. The national trust bank is supervised by the Office of the Comptroller of the Currency. The arrangement was covered in an earlier story on OCC-regulated custody for wrapped Bitcoin.

The reserve structure relies on disclosed Bitcoin reserve addresses and Chainlink Proof of Reserve. Together they let market participants compare the BTC held in reserve with the token's outstanding supply.

Bitcoin does not run natively in Ethereum smart-contract applications. Wrapped tokens such as cirBTC represent the asset on another blockchain while the native BTC stays with a custodian.

## Links in this article

- [OCC-regulated custody for wrapped Bitcoin](https://www.tokenpost.com/news/regulation/23558)