cBTC Earn Vault on Citrea: earn yield on your BTC

Citrea's cBTC Earn Vault lets Bitcoin holders earn yield while their position stays priced in BTC. Clearstar Labs curates it, Noon Capital runs the base strategy, and Upshift runs the vault and the interface depositors use.

A holder who deposits 1 cBTC into the cBTC Earn Vault on Citrea gets back vault shares priced in cBTC, and the share price rises as the strategy earns. Behind the deposit, the curator borrows dollars against the cBTC. Noon Capital puts them to work, and the spread comes back as BTC. CTR incentives are paid on top through Merkl. The vault opened on 1 October 2026, and Upshift provides the vault infrastructure and the deposit interface.

Deposit cBTC: app.upshift.finance/vaults/citrea-mainnet/cbtc-earn-vault

What cBTC is

cBTC is Bitcoin on Citrea, a ZK rollup that settles to Bitcoin. BTC moves onto Citrea through Clementine, a bridge built on BitVM, and Citrea describes cBTC as the first trust-minimized BTC on a fully programmable platform. According to Citrea's launch announcement, cBTC had processed over $65M in volume by 1 October 2026, and Clementine had bridged more than 190 BTC.

Citrea built the vault so holders earn on BTC without converting into stablecoins or other assets, and your position stays in cBTC from deposit to withdrawal. How to earn yield on Bitcoin compares the other routes, and wrapped Bitcoin explained covers how the different BTC tokens are backed.

Step 1: you deposit cBTC and receive vault shares

You deposit cBTC on the Upshift vault page and receive shares in your own wallet. The vault's net asset value is kept in cBTC. The number of cBTC each share redeems for goes up as yield comes in. Withdrawals follow the terms shown on the vault page. The contract is public on the Citrea explorer.

Step 2: Clearstar borrows dollars against the cBTC

Clearstar Labs, a Swiss risk curation firm, runs the vault as its curator. It posts the vault's cBTC as collateral on the Citrea Morpho ctUSD market and borrows ctUSD, Citrea's dollar stablecoin. This is a carry trade, the same basic move a lot of BTC treasuries and funds run by hand, except here the curator handles the borrow, the allocation and the conversion back to BTC inside one vault. It works the way a homeowner might borrow against a house and put the cash in an account paying more than the mortgage rate: the house stays theirs, and the profit is the gap between the two rates.

The curator sets the size of the borrow against the cBTC. If BTC falls sharply, it has to cut the loan before the lending market liquidates any collateral.

Step 3: Noon Capital earns on the dollars

Clearstar allocates the borrowed dollars to Noon Capital, the vault's main strategy partner. Noon runs looping strategies with sUSN, its staked stablecoin. sUSN earns from Noon's reserve, which Noon's documentation lists as tokenized T-bills, CLOs, private credit, DeFi lending, principal tokens and funding-rate trades, with a mix that shifts as markets move. Noon already manages over 80 cBTC in its own cBTC vault, per Citrea's announcement. sUSN holders receive 80% of the protocol's distributable returns. Clearstar can resize the allocation as Noon's rate and the borrow rate move.

Step 4: the spread comes back as BTC

Clearstar converts the dollar yield above the borrow cost back into BTC. That keeps the vault's accounting in cBTC, and the gain shows up as a higher share price. Citrea says the strategy will change as its ecosystem grows. The curator can add or swap venues within the mandate.

CTR incentives run alongside the strategy. Citrea has committed them for the vault's first 6 months, though the amount can change with the vault's TVL. They accrue on Merkl and you claim them there. The Upshift vault page shows one combined APY and splits it into strategy yield and annualized CTR incentives.

Risks to size first

• BTC price: a sharp fall in BTC pushes the borrow closer to its collateral limit, and the curator has to cut the loan in time.
• Spread: if the ctUSD borrow rate rises above what sUSN earns, the base strategy earns less or loses money until it's resized.
• Strategy and exit timing: sUSN carries Noon's own strategy risk, and unstaking sUSN back to USN takes a 7-day cooldown, per Noon's docs.
• Smart contracts and the bridge: the position relies on the vault, the lending market, Noon's contracts and the Clementine bridge.
• Incentives: CTR rewards vary with TVL and with the CTR price.

Always make sure to do your own research and be aware of the above and any other risks before depositing.

Why the vault runs on Upshift

Upshift is onchain yield infrastructure that lets fintechs and asset managers offer yield inside their own products. Partners start with 24/7 tokenized money market funds and add higher-yield strategies, from lending to basis trades, on the same integration. A professional curator runs each stablecoin, BTC or ETH vault within risk limits set in advance, and depositors keep custody of their vault shares throughout.

Every Upshift vault is priced and settled by Upshift, which validates the curator's net asset value before it reaches depositors. The vault owner is a multisig, and the contracts have been through 11 smart contract audits by 6 independent firms. Citrea plans to bring the cBTC Earn Vault into neobanks next, which a vault on Upshift supports through the Upshift SDK. A fintech can list the same vault in its own app, and its users earn on BTC without leaving it. How exchanges build an Earn product covers how that works.

Keep reading

• How to earn yield on Bitcoin. The main routes compared, from lending to basis trades.
• How onchain yield vaults are secured. Contract, oracle and operator controls.
• Upshift is live on Base with Clearstar's cbXRP yield vault. Another Clearstar-curated vault on Upshift.