State Treasury/Trust Portfolio

Information about state operating funds investments

The hundreds of operating accounts in the state treasury or the custody of the State Treasurer are pooled for banking and investment purposes into a portfolio called the Treasury/Trust portfolio. By pooling the balances of these accounts, the state benefits from substantially lower banking fees and earns millions of dollars annually in additional interest.

The Treasury/Trust investment portfolio is divided into liquidity and core components. The liquidity portfolio is invested in highly liquid instruments, with a balance that fluctuates widely as a function of daily cash flows in and out of the state treasury. Funds that are not expected to be needed for short term cash flows are allocated to the core portfolio, where they are invested in US Treasury and agency securities with slightly longer maturities, using a consistent investment strategy.

See the links below for more detailed information about the holdings and performance of OST's Treasury/Trust portfolio.

The Washington State Investment Board invests pensions and certain other long-term balances for the state.  For information about the State Investment Board, go to


Amanda Hutson, Investments