A money market deposit account is a hybrid savings account that pays interest tied to market rates, requires a higher opening balance than a regular savings account, and limits how often you can withdraw money each month.
Money market deposit accounts (MMDAs) sit between a regular savings account and a money market fund. Your bank holds the money, insures it through the FDIC up to $250,000, and pays you interest based on current market conditions. In exchange, you agree to keep a minimum balance—often $2,500 to $25,000 depending on the bank—and you can only make a limited number of withdrawals per month before fees kick in.
The appeal is the interest rate. When the Federal Reserve raises its benchmark rate, money market deposit accounts typically respond faster than regular savings accounts do. If you have money you won't need for a few months but want it to stay liquid (meaning you can access it without penalty), an MMDA can earn more than a savings account at the same bank. The catch is that the rate can drop just as fast when the Fed cuts rates, and you lose the flexibility of unlimited withdrawals.
Key Takeaways
- Money market deposit accounts require a higher minimum balance than savings accounts, usually between $2,500 and $25,000, and your bank sets this threshold.
- The interest rate on an MMDA is variable and tied to market conditions, so it rises and falls with Federal Reserve rate changes, not on a fixed schedule.
- Federal law limits you to six withdrawals per month before your bank can charge a fee or close the account, though this rule applies differently to transfers and in-person withdrawals.
- Your money is FDIC-insured up to $250,000, the same as a regular savings account, so the bank's failure does not put your principal at risk.
- An MMDA makes sense if you have a lump sum you want to earn interest on without locking it away, but a high-yield savings account may offer better rates with no withdrawal limits.
How the interest rate works and when it changes
The interest rate on a money market deposit account is not fixed. Your bank sets it based on what the Federal Reserve is doing and what other banks are offering. When the Fed raises its benchmark rate, banks typically raise MMDA rates within days or weeks. When the Fed cuts rates, banks cut MMDA rates just as quickly—sometimes faster.
This is different from a certificate of deposit (CD), where your rate is locked in for the entire term. With an MMDA, your rate can change at any time, and your bank is required to notify you before the change takes effect. Some banks notify you by email or through your online account; others mail a notice. Check your account agreement to see how your bank communicates rate changes.
The actual rate you receive depends on the bank. A large national bank might offer 4.50% on an MMDA while a credit union or online bank offers 5.25% on the same account type. Shop around before opening one, because the difference between banks can add up to hundreds of dollars per year on a $10,000 balance.
Withdrawal limits and what happens when you exceed them
Federal law allows you to make up to six withdrawals per month from a money market deposit account before your bank can charge a fee or take action. This limit applies to transfers out of the account, checks written against the account, and debit card withdrawals. In-person withdrawals at a branch and ATM withdrawals sometimes fall outside this limit, depending on your bank's policy—check your account agreement.
If you exceed six withdrawals in a month, your bank can charge a fee (typically $25 to $35 per excess withdrawal) or convert your account to a regular savings account, which usually means a lower interest rate. Some banks will close the account if you repeatedly exceed the limit. The six-withdrawal rule exists because money market deposit accounts are meant for money you hold but do not actively spend from—they are not checking accounts.
If you need to access your money more often, a high-yield savings account is a better choice. Most online banks offer high-yield savings accounts with no withdrawal limits and rates competitive with or better than MMDAs, though the rate is still variable.
Minimum balance requirements and fees
Most banks require you to maintain a minimum balance to open an MMDA and to keep the account open. This minimum varies widely: some online banks have no minimum, while others require $2,500, $10,000, or even $25,000. If your balance falls below the minimum, your bank may charge a monthly fee (usually $10 to $25) or close the account.
Beyond the minimum balance requirement, watch for these fees: excess withdrawal fees (charged when you exceed six withdrawals per month), monthly maintenance fees (charged even if you meet the minimum), and fees for closing the account early. Some banks waive the monthly fee if you maintain a higher balance or if you have other accounts with them. Read the fee schedule before you open an account.
The interest you earn should outpace any fees. If a bank requires a $10,000 minimum and pays 4.75% annually, you earn about $475 per year before fees. A $15 monthly maintenance fee would cost $180 per year, leaving you with $295 in net earnings. If the same bank offers a high-yield savings account with no fee and a 4.50% rate, you would earn $450 per year—more than the MMDA after fees.
FDIC insurance and what it covers
Money in a money market deposit account is insured by the FDIC (Federal Deposit Insurance Corporation) up to $250,000 per depositor, per bank. This means if your bank fails, the FDIC will reimburse you for the full balance up to $250,000. This protection applies to the principal and any interest you have earned.
The $250,000 limit is per bank, not per account. If you have an MMDA and a savings account at the same bank, they share the same $250,000 insurance limit. If you have $150,000 in an MMDA and $120,000 in a savings account at the same bank, only $250,000 is insured; you would lose $20,000 if the bank failed. To protect more than $250,000, open accounts at different banks.
FDIC insurance does not protect you from market risk or interest rate risk. If you lock your money in an MMDA and rates fall, you earn less interest. If you need your money and rates have risen, you have not locked in a higher rate. These are trade-offs you accept when you choose an MMDA over a CD or a money market fund.
When an MMDA makes sense versus other accounts
An MMDA is useful if you have a sum of money—say, $15,000 from a bonus or inheritance—that you want to earn interest on without committing to a specific term. You can access the money if you need it, but you are not spending from it regularly. The higher interest rate compared to a regular savings account is the main benefit.
A high-yield savings account often offers a better deal. Many online banks pay rates equal to or higher than MMDAs, have no minimum balance, charge no fees, and place no limits on withdrawals. The only reason to choose an MMDA over a high-yield savings account is if your bank offers a significantly higher rate on the MMDA or if you prefer banking in person at a branch.
A CD is better if you know you will not need the money for a set period—say, six months or one year. CDs lock in a fixed rate, so you are protected if rates fall. The trade-off is that you cannot access the money without paying an early withdrawal penalty. A money market fund is similar to an MMDA but is not FDIC-insured and is sold through investment accounts, not banks.
How to open an MMDA and what to compare
To open a money market deposit account, visit your bank's website or branch and look for the MMDA product. You will need to provide your name, address, Social Security number, and initial deposit. Most banks let you open an account online in 10 to 15 minutes. Some require you to visit a branch in person.
Before you open an account, compare these details across at least three banks: the current interest rate, the minimum balance to open and maintain the account, monthly fees, excess withdrawal fees, and how often the rate changes. Use a spreadsheet to calculate the annual earnings on your expected balance, minus any fees. A rate that looks high might not be worth it if the minimum balance is too high or fees are steep.
Check whether the bank is FDIC-insured by searching the FDIC's Bank Find tool on their website. This takes 30 seconds and confirms your money is protected. Once you open an account, set a calendar reminder to review the rate every three months. If another bank offers a significantly higher rate, you can transfer your money—most banks make this easy.
Frequently Asked Questions
Can I write checks from a money market deposit account?
Yes, most banks allow you to write checks from an MMDA, though the number of checks you can write per month counts toward your six-withdrawal limit. Some banks limit you to three checks per month. Check your account agreement to see whether checks are allowed and how they are counted.
What happens to my interest if I fall below the minimum balance?
Your bank will stop paying interest on the full balance and may charge a monthly fee instead. Some banks pay a lower interest rate on balances below the minimum. If you fall below the minimum, your bank will notify you and give you a grace period—usually 10 to 30 days—to bring the balance back up before fees apply.
Is a money market deposit account the same as a money market fund?
No. A money market deposit account is a bank account insured by the FDIC. A money market fund is an investment product sold through a brokerage and is not FDIC-insured. Money market funds can lose value, though the risk is low. An MMDA is safer but typically offers a lower return.
Can I move money from an MMDA to another account without using a withdrawal?
This depends on your bank. Some banks count transfers to other accounts as withdrawals and count them toward your six-withdrawal limit. Others allow unlimited transfers to accounts at the same bank. Ask your bank before you open the account, because this rule varies widely.
What if the interest rate drops after I open the account?
You have no obligation to stay. You can close the MMDA and move your money to another bank offering a higher rate. Most banks do not charge a fee to close an account, though some charge a small fee if you close within 30 or 90 days of opening. Check the account agreement before you open.