Debt Ceiling
A protocol-set maximum amount of debt that can be issued against a specific collateral type or market, limiting the lending protocol's total exposure to that asset.
A debt ceiling is a risk parameter (see Kaavon's "Risk Parameter" glossary definition) set by a DeFi lending protocol's governance, capping the maximum total amount of debt that can be issued against a specific collateral type or within a specific isolated market (see Kaavon's "Isolated Market" glossary definition), regardless of how much of that collateral is deposited. Once a collateral type's outstanding debt reaches its ceiling, no further borrowing against that collateral is possible until existing debt is repaid, even if more of the collateral asset is deposited.
Debt ceilings exist specifically to limit a protocol's maximum exposure to any single, potentially riskier or more volatile collateral asset, containing the potential damage from that asset's price collapsing or its market becoming illiquid, without needing to ban borrowing against it entirely. Setting debt ceilings appropriately involves a tradeoff between capital efficiency (a lower ceiling limits how much borrowing demand against that asset a protocol can actually serve) and risk containment (a higher ceiling increases the protocol's maximum potential loss if that specific collateral fails).
Examples
- A lending protocol might set a conservative debt ceiling for a newly listed, more volatile collateral asset, only raising it gradually as the asset demonstrates sustained liquidity and price stability.
- Once a collateral type's debt ceiling is reached, no further borrowing against that asset is possible, even if additional units of that same collateral are deposited.