Compound Finance Tax Guide: cTokens, COMP Rewards, and Interest
Key Takeaways
- Depositing assets into Compound to receive cTokens is likely a taxable swap; your cost basis is the FMV of assets deposited.
- cTokens appreciate in value as interest accrues; the gain is taxable when you redeem cTokens for the underlying assets.
- COMP governance tokens distributed to lenders and borrowers are ordinary income at FMV when received.
- Borrowing on Compound is not a taxable event, but liquidation of collateral is a taxable sale.
- cToken appreciation is a capital gain or loss depending on holding period.
What Is Compound Finance?
Compound Finance is a decentralized lending protocol that allows users to deposit crypto to earn interest and borrow against collateral. Founded in 2018, Compound was one of the first yield-bearing DeFi protocols.
When you deposit assets into Compound, you receive cTokens. Unlike Aave's aTokens (which increase in quantity), cTokens work differently: your cToken balance stays the same, but each cToken becomes more valuable as interest accrues. It's like a traditional bond: you own the same number of cTokens, but they're worth more over time.
This different mechanism creates distinct tax treatment compared to Aave. Understanding cToken economics is essential for accurate tax reporting. For a broader overview of crypto tax obligations, see our complete guide to crypto taxes.
How cTokens Work and Appreciate
Here's the key difference between cTokens and aTokens:
When you deposit 10,000 DAI into Compound, you receive approximately 467 cDAI (the ratio depends on the exchange rate between DAI and cDAI at that moment). Over time, as interest accrues, your 467 cDAI become worth more. Each cDAI represents a larger claim on the underlying DAI.
After one year with interest accrual, your 467 cDAI might be redeemable for 10,500 DAI.
From a tax perspective, this is crucial: your cToken balance (467 cDAI) stays constant, but its value increases. This appreciation is a capital gain.
Depositing Into Compound
When you supply assets to Compound and receive cTokens, you're likely triggering a taxable event. Your cost basis in the cTokens equals the FMV of the assets you deposited.
If you deposit $10,000 of USDC and receive 467 cUSDC, your cost basis in cUSDC is $10,000. This establishes the baseline for calculating future gains and losses.
Most tax professionals treat cToken deposits as taxable swaps (you exchanged USDC for cUSDC), establishing cost basis but not typically recognizing an immediate gain or loss (since the FMV of cUSDC equals what you deposited).
cToken Appreciation and Interest Income
As interest accrues on your Compound deposit, the value of each cToken increases. If each cUSDC was worth $21.42 when you deposited and is now worth $22.86 after one year, your 467 cUSDC have appreciated from $10,000 to $10,671.
This appreciation represents accrued interest. The tax question: when do you owe tax on it?
Similar to Aave, the IRS view is that interest is taxable when you have dominion and control over it. With Compound, that means annually as it accrues, though many taxpayers report it upon redemption.
At redemption, the calculation is:
Interest Income = FMV of Assets Redeemed - Cost Basis of cTokens
If your cost basis is $10,000 and you redeem for $10,671 worth of USDC, you have $671 of ordinary income from interest.
Redeeming cTokens and Capital Gains
When you redeem cTokens for the underlying assets, you're triggering a taxable disposition. Calculate your gain or loss:
Gain/Loss = FMV of Assets Received - Cost Basis of cTokens
The holding period determines the character: if you held the cTokens less than a year, it's short-term capital gain (taxed as ordinary income). Over a year, it's long-term capital gain (preferential rates).
For many Compound users, the gain is primarily from interest accrual (ordinary income) plus potentially some cToken appreciation (capital gain). The distinction matters for tax rate purposes.
Receiving COMP Governance Tokens
COMP is Compound's governance token. The protocol distributes COMP to lenders and borrowers as an incentive to use the protocol. When you deposit or borrow on Compound, you accrue COMP tokens.
When you claim your COMP (which you must do manually; it doesn't accrue automatically to your wallet), the COMP is ordinary income at FMV when received. This is consistent with the IRS treatment of crypto staking taxes (Rev. Rul. 2023-14).
The FMV at receipt becomes your cost basis in COMP. Any future appreciation is a capital gain or loss depending on when you sell.
Example: You claim 10 COMP when COMP is worth $75 each. You have $750 of ordinary income. Your cost basis in the 10 COMP is $750. If you sell it later for $800, you have a $50 capital gain.
Borrowing on Compound
Borrowing on Compound is not a taxable event. When you deposit collateral and borrow against it, you're not selling the collateral; you're using it as security for a loan.
This remains true regardless of the interest rate you pay or the amount you borrow.
Interest on borrowed funds: If you borrowed cUSDC and used it for investment purposes, the interest paid is potentially deductible as an investment expense. If borrowed for personal use, it's not deductible. Consult your CPA about your specific situation.
Liquidation and Forced Closure
If your collateral value falls below Compound's required ratio, your collateral can be liquidated. Someone else repays your debt and takes your collateral at a discount, keeping the liquidation bonus.
Liquidation is a taxable sale. You must report a capital gain or loss based on the FMV of collateral when liquidated versus its cost basis.
This is an involuntary transaction, but the IRS taxes it like any other sale. Document the liquidation price carefully.
How to Track Compound Transactions
Accurate tracking requires capturing several data points for each transaction:
For deposits:
- Deposit date and amount (in dollars)
- FMV of assets deposited
- cToken symbol and quantity received
For redemptions:
- Redemption date
- cToken quantity redeemed
- FMV of underlying assets received
- Interest accrued (the increase in value from deposit to redemption)
For COMP rewards:
- Date received
- Quantity and FMV of COMP at receipt
For liquidations:
- Date liquidated
- Asset liquidated and quantity
- Liquidation price (FMV)
- Cost basis of liquidated asset
Tools like FastCryptoTax can import your Compound activity via your wallet address and automatically calculate cToken appreciation, interest income, and COMP rewards.