What a Certificate of Deposit Actually Does

A certificate of deposit (CD) is an agreement between you and a bank where you give the bank a sum of money for a fixed period of time, and the bank pays you a set interest rate on that money. You cannot touch the money during that period without paying a penalty. In exchange for locking your money away, the bank gives you a higher interest rate than you would get in a regular savings account.

Think of it this way: the bank wants to know it can count on having your money available for a specific stretch of time. That certainty is valuable to them, so they reward you for it. You trade access to your cash for a better return.

Key Takeaways

  • You deposit a lump sum of money and agree not to touch it for a set period—typically three months to five years—in exchange for a fixed interest rate.
  • The bank pays you interest on your deposit, and that interest is locked in from the day you open the CD; it will not change even if rates rise or fall.
  • If you withdraw your money before the term ends, you pay an early withdrawal penalty, which is usually a certain number of months' worth of interest.
  • When your CD term ends (called the maturity date), you can withdraw your money and interest penalty-free, or let it roll over into a new CD at the current rate.
  • CDs are insured by the FDIC up to $250,000 per depositor per bank, so your principal is protected even if the bank fails.

How Interest Works on a CD

When you open a CD, the bank tells you the annual percentage yield (APY) you will earn. This is the actual return you will get on your money over one year, accounting for how often the bank compounds your interest (adds earned interest back into your account so you earn interest on that interest too).

The interest rate on a CD is fixed. If you open a one-year CD at 4.5% APY, you will earn 4.5% on your deposit for the entire year, regardless of whether interest rates in the market go up or down. This is different from a savings account, where the rate can change at any time. The tradeoff is that you cannot access your money without a penalty.

Interest is usually paid out at maturity—meaning when your CD term ends, you receive your original deposit plus all the interest earned. Some CDs pay interest monthly or quarterly, but most consumer CDs pay it all at once at the end.

The Term: How Long Your Money Is Locked Away

Every CD has a term, which is the length of time you agree to leave your money in the account. Common terms are three months, six months, one year, two years, three years, and five years. Some banks offer terms as short as one month or as long as ten years, but these are less common.

The term you choose affects the interest rate you receive. Generally, longer terms come with higher rates because you are giving the bank more certainty about having your money. A five-year CD will usually pay more than a one-year CD. However, this is not always true—sometimes rates are inverted, meaning shorter terms pay more. It depends on what the bank is offering at that moment.

You choose the term when you open the CD. Once you have chosen it, you cannot change it without withdrawing the money and paying the penalty.

What Happens If You Need Your Money Early

If you withdraw money from a CD before the term ends, you pay an early withdrawal penalty. This penalty is usually expressed as a number of months of interest. For example, a penalty might be three months of interest, or six months of interest. A few banks charge a flat dollar amount instead.

Here is a concrete example: You open a $10,000 CD with a 4% APY and a six-month early withdrawal penalty. After three months, you need the money. Your earned interest so far is about $100. The penalty is six months of interest, which would be about $200. You would receive $10,000 (your principal) minus $200 (the penalty), for a total of $9,800. You lose money, and you also lose the interest you already earned.

This is why CDs work best for money you know you will not need. If there is any chance you might need the cash, a regular savings account is safer, even if the rate is lower.

Maturity and What Happens Next

When your CD term ends, you reach the maturity date. At this point, you can do one of three things: withdraw your money penalty-free, let the CD roll over into a new CD, or move the money to a different account.

Most banks have a grace period after maturity—usually seven to ten days—during which you can withdraw without penalty. If you do nothing during that window, many banks automatically roll your CD into a new one at the current rate. This new CD will have the same term as the old one unless you change it. Read your CD agreement to see what your bank does, because the new rate might be lower than what you had.

If you want to avoid an automatic rollover, contact your bank before the maturity date and tell them what you want to do. This gives you control over whether your money stays in a CD and at what rate.

How CDs Compare to Savings Accounts and Money Market Accounts

A savings account lets you deposit and withdraw money whenever you want, with no penalty. The tradeoff is that savings account rates are almost always lower than CD rates. You pay for flexibility with a lower return.

A money market account is a hybrid. It usually pays a higher rate than a savings account but lower than a CD, and it gives you limited withdrawal rights—you can make a few withdrawals per month without penalty, but not unlimited ones. Money market accounts are useful if you want some of the rate benefit of a CD but need occasional access to your cash.

CDs are best for money you will not need for a specific period and want to lock into a may provide rate. Savings accounts are best for emergency funds and money you might need soon. Money market accounts split the difference.

FDIC Insurance and Your Protection

CDs held at FDIC-insured banks are protected by FDIC insurance up to $250,000 per depositor per bank. This means if the bank fails, the government guarantees you will get your money back, up to that limit. Your principal and all earned interest are covered.

If you have more than $250,000 to deposit, you can spread it across multiple banks to keep everything insured. For example, $250,000 at Bank A and $250,000 at Bank B are both fully covered. You can also open a CD in your name alone and another in joint ownership with a spouse; these are insured separately.

Check that your bank is FDIC-insured before you open a CD. Most traditional banks are, but some online banks and credit unions are not. The FDIC website has a tool to search for insured institutions.

Frequently Asked Questions

Can I add more money to a CD after I open it?

No. A CD is a fixed deposit. Once you open it with a set amount, you cannot add to it. If you want to deposit more money, you would need to open a separate CD. Some banks let you open multiple CDs at once if you want to split your money across different terms.

What happens to my interest if I withdraw early?

You lose the penalty amount, which is usually several months of interest. You may also lose some or all of the interest you have already earned, depending on how the penalty is calculated and how long you held the CD. Always ask your bank exactly how the penalty works before you open a CD.

Is the interest rate on a CD may provide to stay the same?

Yes, for the entire term. The rate you lock in when you open the CD will not change, even if market rates rise or fall. This is one of the main benefits of a CD—you know exactly what you will earn.

What is the difference between APY and APR on a CD?

APY (annual percentage yield) is what you actually earn when interest is compounded. APR (annual percentage rate) is the base rate without compounding. For CDs, always look at the APY, because that is your real return. Banks are required to show you the APY prominently.

Can I use a CD as collateral for a loan?

Yes. Some banks offer CD-secured loans, where you borrow against your CD without withdrawing it. You keep earning interest on the CD while you repay the loan. This avoids the early withdrawal penalty and can be useful if you need cash but want to keep your CD intact.