What is Money Market Account?

Legal Definition
A money market account (MMA) or money market deposit account (MMDA) is a financial account that pays interest based on current interest rates in the money markets.

Money market accounts typically have a relatively high rate of interest and require a higher minimum balance (anywhere from $1,000 to $10,000 or $25,000) to earn interest or avoid monthly fees. Like other bank deposits, they are liabilities from the bank's perspective. They should not be confused with money market funds.
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Legal Definition
Special savings account that pays a varying interest rate higher on average than an ordinary savings account's interest rate. There are constraints on this special account., however. A specific minimum credit balance is required to retain the special interest rate. A limited number of checks can be written on the account in any one month. No limit on fund transfers over the bank's counter or through automated teller machines (ATM). Like an ordinary savings account balance, this account's balance is covered under deposit insurance . Also known as money market deposit account (MMDA).