Calculate how much your money market account will grow with compound interest and regular deposits.
Steady savings
Over 5 years, you'll earn $6,103 in interest. Consider a longer time horizon or higher rate to maximize growth.
This calculator provides estimates based on the inputs provided. Actual returns may vary. Money market rates are variable and can change at any time. FDIC insurance covers deposits up to \$250,000.
A money market account (MMA) is a type of savings account offered by banks and credit unions that typically pays higher interest rates than traditional savings accounts. Money market accounts combine features of both savings and checking accounts—they earn competitive interest while offering limited check-writing privileges and debit card access.
Money market accounts are insured by the Federal Deposit Insurance Corporation (FDIC) for banks or the National Credit Union Administration (NCUA) for credit unions, up to $250,000 per depositor per institution. This makes them one of the safest places to park your cash while earning a return.
The name "money market" comes from the short-term debt instruments that banks invest in using your deposits, including Treasury bills, certificates of deposit, and commercial paper. These low-risk investments allow banks to offer competitive rates while maintaining liquidity.
Money market accounts use compound interest, where you earn interest not just on your initial deposit but also on the interest you've already earned. This compounding effect accelerates your savings growth over time.
The compound interest formula is:
Where:
For accounts with regular monthly deposits, the calculation becomes more complex:
Where PMT is the periodic deposit amount.
The more frequently interest compounds, the more you earn. Here's how different compounding frequencies affect a $10,000 deposit at 4.5% APY over one year:
| Compounding | Times/Year | Final Balance | Interest Earned |
|---|---|---|---|
| Daily | 365 | $10,460.17 | $460.17 |
| Monthly | 12 | $10,459.06 | $459.06 |
| Quarterly | 4 | $10,456.79 | $456.79 |
| Semi-annual | 2 | $10,455.06 | $455.06 |
| Annual | 1 | $10,450.00 | $450.00 |
While the differences seem small over one year, they become more significant with larger balances and longer time periods.
When comparing money market accounts, you'll see two interest rate terms:
Annual Percentage Rate (APR) is the base interest rate without accounting for compounding. This is the stated rate banks use before applying compound interest.
Annual Percentage Yield (APY) includes the effect of compounding and represents your actual annual return. APY is always equal to or higher than APR.
The relationship between APR and APY is:
When comparing accounts, always look at the APY since it reflects your true earnings. A 4.5% APY account will earn more than a 4.5% APR account because the APY already accounts for compounding.
Money market rates fluctuate based on the Federal Reserve's benchmark interest rate and overall economic conditions. As of late 2024, competitive money market accounts offer APYs between 4% and 5%, significantly higher than the national average savings rate of around 0.45%.
Online banks and credit unions typically offer higher rates than traditional brick-and-mortar banks due to lower operating costs. When shopping for a money market account, consider:
A larger initial deposit means more money earning interest from day one. The power of compound interest is most evident with larger principal amounts. For example, at 4.5% APY:
Consistent monthly deposits dramatically increase your final balance. Adding just $200 per month to a $10,000 initial deposit at 4.5% APY grows to over $41,000 in 10 years—compared to just $15,600 without monthly contributions.
Small differences in APY compound into significant amounts over time. The difference between 3.5% and 4.5% on $50,000 over 10 years is approximately $6,800.
The longer you save, the more compound interest works in your favor. A $10,000 deposit at 4.5% APY grows to:
| Years | Balance | Interest Earned |
|---|---|---|
| 1 | $10,460 | $460 |
| 5 | $12,462 | $2,462 |
| 10 | $15,530 | $5,530 |
| 20 | $24,117 | $14,117 |
| 30 | $37,453 | $27,453 |
| Feature | Money Market | Savings Account |
|---|---|---|
| Interest rate | Generally higher | Generally lower |
| Minimum balance | Often $1,000-25,000 | Often $0-500 |
| Check writing | Usually limited | Rarely available |
| Debit card | Often included | Sometimes available |
| Transaction limits | 6 per month (typical) | 6 per month (typical) |
| FDIC/NCUA insurance | Yes | Yes |
CDs typically offer higher rates than money market accounts but require locking up your money for a fixed term (3 months to 5 years). Money market accounts provide flexibility—you can withdraw funds anytime without penalty.
| Feature | Money Market | CD |
|---|---|---|
| Liquidity | High | Low (early withdrawal penalties) |
| Interest rate | Variable | Fixed |
| Access to funds | Anytime | At maturity |
| Rate guarantee | No | Yes, for the term |
High-yield savings accounts from online banks often match or exceed money market rates without minimum balance requirements. The main advantage of money market accounts is the check-writing and debit card access, which can be useful for emergency funds you might need quick access to.
Money market accounts are ideal for emergency funds because they offer:
Financial advisors recommend keeping 3-6 months of expenses in an emergency fund. A money market account lets this money grow while remaining accessible.
For goals within 1-3 years (car purchase, vacation, home down payment), money market accounts provide a safe place to grow your savings without market risk. Unlike stocks or bonds, your principal is protected.
Interest rates vary significantly between institutions. Review your money market rate quarterly and be willing to move funds to earn higher yields. Many banks offer promotional rates for new customers.
Some savers combine money market accounts with CDs in a "laddering" strategy:
This balances liquidity with potentially higher CD rates.
This calculator provides estimates based on the following assumptions:
Constant interest rate: The APY you enter remains unchanged throughout the entire time period. In reality, money market rates fluctuate with market conditions and Federal Reserve decisions.
Consistent monthly deposits: The calculation assumes you make the same monthly deposit every month without fail.
No withdrawals: The projection assumes you don't withdraw any funds during the savings period.
No fees: Monthly maintenance fees, excess transaction fees, or other charges are not included and would reduce actual returns.
Below FDIC limits: This calculator doesn't account for the $250,000 FDIC insurance limit. Amounts above this limit in a single institution are not federally insured.
Interest earned in money market accounts is generally taxable as ordinary income. Banks report interest earnings over $10 annually on Form 1099-INT.
Your tax liability depends on your marginal tax bracket:
| Tax Bracket | Tax on $1,000 Interest |
|---|---|
| 10% | $100 |
| 12% | $120 |
| 22% | $220 |
| 24% | $240 |
| 32% | $320 |
| 35% | $350 |
| 37% | $370 |
For high earners, consider tax-advantaged alternatives like municipal money market funds, which earn interest exempt from federal taxes (and sometimes state taxes for in-state bonds).
Money market accounts are worth considering if you want higher yields than traditional savings while maintaining easy access to your funds. They're particularly valuable for emergency funds and short-term savings goals.
Minimums vary widely—from $0 at some online banks to $25,000 or more at traditional banks. However, you may need to maintain a minimum balance to earn the advertised APY or avoid monthly fees.
Your principal is protected in an FDIC-insured money market account (up to $250,000). However, if inflation exceeds your interest rate, your money loses purchasing power over time.
Review rates quarterly. If your current rate drops significantly below competitors, consider switching banks. Many institutions make it easy to transfer funds electronically.
Money market accounts are bank deposits insured by FDIC/NCUA. Money market funds are investment products that buy short-term securities—they're not FDIC-insured and can lose value, though they rarely do.