Money Market Funds

A cash-management analyst examining a diversified basket of short-term government and corporate instruments in a quiet fund operations office.

Money Market Funds Explainer

A money market fund is a mutual fund that invests in high-quality, short-term debt instruments, cash, and cash equivalents. Investors often use these funds for cash management because shares are generally redeemable on business days and returns tend to follow short-term interest rates.

Government, prime, and tax-exempt funds hold different assets and follow different rules. Many retail and government funds seek a stable one-dollar net asset value, while institutional prime and tax-exempt funds generally use a floating market-based NAV. Dividends, not a guaranteed bank rate, produce the investor’s return.

Money market funds manage maturity, liquidity, credit quality, and diversification under securities regulations. Depending on fund type and circumstances, fees or other liquidity tools can affect redemptions. Expenses reduce yield, and a stable-price objective does not guarantee that a fund cannot lose value.

Fund shares are securities and are not FDIC-insured bank deposits. A money market deposit account is a different bank product. Investors should review the prospectus, portfolio type, expense ratio, seven-day yield, tax treatment, liquidity policies, and sponsor support assumptions rather than choosing solely by the highest displayed yield.

Money market funds own short-term instruments and issue redeemable shares.

They are not FDIC-insured deposits.

Government, prime, and tax-exempt funds hold different assets.

Stable and floating NAV rules also differ.

Dividends reflect current short-term rates after expenses.

Liquidity and credit risks remain.

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