CDOs are larger financial products that institutions then sell on a secondary market. Each CDO may include credit card debt, mortgages, auto loans and corporate debt. They are considered collateralized because borrowers have promised to repay the debt within each part of the CDO.

A single-name CDS references only one security and the credit risk to be transferred in the swap may be very large. In contrast, a synthetic CDO references a portfolio of securities and is sliced into various tranches of risk, with progressively higher levels of risk.

Credit default swaps are also used to structure synthetic collateralized debt obligations (CDOs). Instead of owning bonds or loans, a synthetic CDO gets credit exposure to a portfolio of fixed income assets without owning those assets through the use of CDS. CDOs are viewed as complex and opaque financial instruments.

A collateralized debt obligation (CDO) is also a fixed-income security that pays interest based on a bundle of underlying debt; but this pool can include a much bigger variety of loans and types of debts.