What Is Money Market Mutual Fund?

A money market fund is a type of mutual fund that puts money into easily accessible, short-term investments. These investments can include cash, securities that are similar to cash, and debt-based securities with a short lifespan and a high credit rating (like U.S. Treasuries). The main goal of money market funds is to provide investors with a safe and low-risk way to access their money quickly. Money market funds are sometimes referred to as money market mutual funds.

Although they may have similar names, a money market fund and a money market account (MMA) are not the same. A money market fund is an investment managed by an investment fund company and does not guarantee the principal amount. On the other hand, a money market account is a type of savings account that earns interest. Financial institutions offer money market accounts, which are insured by the Federal Deposit Insurance Corporation (FDIC) and usually have restricted transaction privileges.

How It Works?

Money market funds operate in a similar manner to regular mutual funds. They offer investors redeemable units or shares and are required to adhere to the guidelines set by financial regulators.

Types of Money Market Funds

Money market funds are categorized into different types based on the assets they invest in, the length of time they are held, and other characteristics.

Pros and Cons

Money market funds compete with bank money market accounts, ultrashort bond funds, and enhanced cash funds. These options can invest in different assets and target higher returns.


  • Very low-risk
  • Highly liquid
  • Better returns than bank accounts


  • Not FDIC-insured
  • No capital appreciation
  • Sensitive to interest rate fluctuations, monetary policy


A money market fund is a type of mutual fund that invests in safe, short-term debt instruments like U.S. Treasuries, commercial paper, and certificates of deposit (CDs). These funds provide investors with high liquidity and a low level of risk. Unlike money market accounts (MMAs), money market funds are not insured by the FDIC and their value can change. They are designed for short-term, easily accessible investments that generate modest income through interest. Money market funds aim to maintain a net asset value (NAV) of $1 per share and are popular for their stability and regular income, although they can be affected by changes in interest rates.

Money market funds have changed their regulations and structure since the 2008 financial crisis to make the market more stable and protect investors. They are still an important part of the capital markets, providing a secure and easily accessible investment choice for both individuals and institutions.