Borrowing Against Crypto Collateral in DeFi: The Tax Treatment

Locking crypto as collateral to borrow another asset, whether a stablecoin or something else, is one of the more common DeFi activities, and it raises a genuinely different tax question to simply buying, selling or swapping. Understanding lending and borrowing crypto as a mechanism is the starting point, since the tax treatment depends heavily on what actually happens to ownership of the collateral throughout the process.

As of 1 July 2027, CGT rules in Australia are set to change. Please visit this page for the revised tax rules.

 

Posting Collateral Is Generally Not a Disposal

Locking crypto as collateral, while retaining the underlying right to reclaim it once the loan is repaid, is generally not treated as a disposal under standard CGT rules, because beneficial ownership has not genuinely changed hands, it is simply restricted from being freely transferred while the loan is active. The borrowed asset received is not income either, it is a loan, a liability rather than an accession to wealth, and receiving it does not trigger a tax event on its own.

This treatment depends entirely on the specific protocol genuinely functioning as a loan rather than a disguised swap. Some protocols structure borrowing in ways that do involve a genuine transfer of the collateral asset to the protocol, which would change this analysis considerably. Reviewing how a specific DeFi protocol is actually structured, rather than assuming every “borrowing” product works identically, matters before assuming the non-disposal treatment applies.

 

Where the Tax Consequences Actually Arise

Interest paid on the borrowed amount is generally not deductible for a personal investor in the same way it might be for a genuine investment loan outside crypto, and this depends on how the borrowed funds are actually used. Where borrowed funds are used to acquire further income-producing crypto assets, interest deductibility becomes a genuinely relevant question worth assessing properly rather than assumed either way, similar to how crypto used in a business context changes what can be claimed.

The real tax event in most borrowing arrangements arises if the collateral is liquidated, meaning the protocol forcibly sells it because its value has fallen below a required threshold relative to the loan. Liquidation is a genuine disposal of the collateral asset, assessed under standard CGT rules using its original cost base against its value at the point of liquidation. This is where borrowing against volatile collateral carries real tax risk on top of the obvious investment risk, similar in character to the risk covered in the broader treatment of margin and leveraged positions.

 

Record-Keeping, Risk and Reporting

Because a borrowing position can remain open for an extended period before any tax event occurs, disciplined record-keeping of the collateral’s original cost base is essential, since it may be needed considerably later, at the point of liquidation or eventual voluntary repayment and withdrawal. Where a position is closed voluntarily by repaying the loan and reclaiming the collateral, there is generally still no disposal, since the same asset that was originally locked is simply returned.

Where liquidation does occur and produces a loss relative to the collateral’s original cost base, that loss is addressed through standard tax loss harvesting and the general treatment of a capital loss. Platform failure adds a further layer of risk, overlapping with the broader treatment of an exchange collapse and general custodial risk, and this needs to be weighed before locking meaningful collateral into any single protocol. All relevant events need to be reported through the standard process in how to declare cryptocurrency on an Australian tax return, and investors newer to this activity should approach it with the same caution outlined for anyone new to crypto tax in Australia, reviewing broader legal risks of crypto investing and the ATO’s data matching capability before assuming borrowing sits outside standard reporting obligations. Positions held across multiple wallets and exchanges, or funded via a stablecoin at the outset, add their own reconciliation layer on top of the core borrowing mechanic.

 

Key Takeaways

Posting crypto as collateral for a DeFi loan is generally not a disposal, provided the underlying right to reclaim it is retained. Receiving the borrowed asset is a liability, not taxable income. The real tax event typically arises on liquidation, where the collateral is forcibly sold, assessed as a standard capital gain or loss against its original cost base. Voluntarily repaying a loan and reclaiming the same collateral generally does not itself trigger a further tax event.

Shepley Capital provides education and market insights, not financial advice. Always conduct your own research before making any investment decisions.