What a CD is and how your money grows

A certificate of deposit (CD) is a bank account where you agree to leave a fixed amount of money untouched for a set period—usually three months to five years—in exchange for a higher interest rate than a regular savings account. The bank pays you interest on that money, and you get the full amount back when the term ends.

The trade-off is simple: you lock up your cash for the duration. If you withdraw before the term is over, the bank charges a early withdrawal penalty, which is a fee that reduces your earnings or principal. The penalty amount varies by bank and by CD term length—a three-month CD might charge one month's interest, while a five-year CD might charge six months' interest. You need to know the penalty before you buy the CD, because it directly affects whether breaking the term makes financial sense.

Interest rates on CDs change based on what the Federal Reserve does with its benchmark rate. When rates rise, new CDs pay more. When rates fall, new CDs pay less. The rate you lock in on the day you open the CD stays the same for the entire term—that's the point of a CD. You know exactly what you'll earn.

Key Takeaways

  • A CD locks your money for a set term (three months to five years) in exchange for a fixed interest rate higher than a savings account.
  • Early withdrawal triggers a penalty fee that reduces your earnings, so only open a CD if you won't need the money before the term ends.
  • The interest rate you receive is locked in on the day you open the CD and does not change, even if bank rates rise or fall.
  • CDs are FDIC-insured up to $250,000 per depositor per bank, so your principal is protected even if the bank fails.
  • Interest earned on a CD is taxable income in the year it accrues, whether you withdraw it or let it stay in the account.

How much you earn and when you get paid

The amount you earn depends on three things: the principal (how much you deposit), the annual percentage yield (APY), and the term length. A bank will show you the APY before you open the CD—that's the rate you'll earn over one year, accounting for compounding. If you open a one-year CD with a $10,000 deposit at 4.5% APY, you'll earn roughly $450 in interest over that year, though the exact amount depends on how the bank compounds (daily, monthly, or quarterly).

Interest accrues during the term, but when you receive it depends on the CD. Some banks add interest to your CD balance monthly or quarterly, so it compounds and earns interest on interest. Others hold all interest until maturity and pay it in a lump sum. Ask the bank which method they use before you open the account—it affects your total earnings, especially on longer terms.

When the CD matures (the term ends), the bank deposits your principal plus all accrued interest into your account. At that point, you can withdraw the money, open a new CD at the current rate, or let it roll over into a new CD at the bank's current rate. Many banks auto-renew CDs unless you tell them not to, so check your account after maturity if you don't want to lock the money up again.

Early withdrawal penalties and when they apply

If you need the money before the CD matures, you can withdraw it, but the bank will charge a penalty. The penalty is usually expressed as a number of months' interest—for example, "180 days' interest" or "three months' interest." On a $10,000 CD earning 4.5% APY, three months' interest is roughly $112.50, so that's what you'd lose if you withdrew early.

Some banks charge a flat dollar amount instead of interest-based penalties, and a few charge a percentage of the principal. The key is to ask for the exact penalty before you open the CD. Write it down. If you think there's any chance you'll need the money, compare the penalty cost to the extra interest you'd earn by keeping it in the CD. Sometimes the penalty is so small that breaking the CD makes sense; sometimes it's large enough that you should keep your money in a regular savings account instead.

A few banks offer no-penalty CDs, which let you withdraw without a fee (though usually not without notice—you may have to wait 7 to 10 days). These CDs pay less interest than standard CDs because the bank is taking on more risk. They're useful if you want a higher rate than savings but need access to your money.

FDIC insurance and what happens if the bank fails

CDs opened at FDIC-insured banks are protected by the Federal Deposit Insurance Corporation up to $250,000 per depositor per bank. That means if the bank fails, the FDIC will return your principal and accrued interest up to that limit. You don't have to do anything—the insurance is automatic.

The $250,000 limit applies per depositor per bank, not per account. If you have a CD and a savings account at the same bank, they count toward the same $250,000 limit. If you want to insure more than $250,000, you can open CDs at different banks—each bank's coverage is separate. Some people also open CDs in different ownership categories (individual, joint, retirement account) at the same bank to increase coverage, because each category has its own $250,000 limit.

CDs at credit unions are insured by the National Credit Union Administration (NCUA) under the same $250,000 per depositor per institution structure. Online banks and brick-and-mortar banks both carry FDIC insurance as long as they're federally chartered. Before you open a CD, confirm the bank or credit union is insured by checking the FDIC or NCUA website.

CD ladders and how to manage multiple CDs

A CD ladder is a strategy where you open several CDs with different maturity dates so that one matures every few months or every year. For example, you might open five one-year CDs, each three months apart. As each one matures, you can withdraw the money, reinvest it in a new CD, or use it for expenses. This approach gives you regular access to portions of your money without early withdrawal penalties.

CD ladders are useful if you want to earn CD rates but also need liquidity. They also protect you if rates are rising—as each CD matures, you can lock in the new (higher) rate instead of being stuck with an old rate for years. The downside is that you have to manage multiple accounts and keep track of maturity dates. Some banks make this easier with online tools that show all your CDs and upcoming maturity dates in one place.

Another approach is a barbell strategy, where you open some short-term CDs (three to six months) and some long-term CDs (three to five years). Short-term CDs mature quickly so you can access money or reinvest at new rates. Long-term CDs lock in higher rates for years. This balances flexibility with earning potential, though it requires managing accounts with different terms.

Tax treatment of CD interest

Interest you earn on a CD is taxable income in the year it accrues, not the year you withdraw it. If you open a CD on January 1 and it matures on December 31, you owe tax on all the interest earned that year, even if you don't touch the money until the next year. The bank will send you a Form 1099-INT in January showing how much interest you earned, and you report that on your tax return.

This matters most for long-term CDs and for people in high tax brackets. If you earn $500 in CD interest and you're in the 24% federal tax bracket, you'll owe roughly $120 in federal tax on that interest alone. Some people use CDs in retirement accounts (like IRAs or 401(k)s) to defer taxes, since interest in those accounts isn't taxed until you withdraw it.

State and local taxes also apply to CD interest in most places. If you live in a state with income tax, you'll owe state tax on the interest too. A few states exempt interest income for people over a certain age, so check your state's rules if that applies to you.

Comparing CD rates and finding the best deal

CD rates vary significantly by bank, term length, and deposit amount. A large national bank might offer 4.0% APY on a one-year CD, while an online bank might offer 4.75% on the same term. Over a year, that 0.75% difference adds up—on a $10,000 CD, it's $75 in extra earnings. Shopping around takes 15 minutes and can save you hundreds of dollars.

Online banks and credit unions typically offer higher rates than brick-and-mortar banks because they have lower overhead costs. Some banks also offer higher rates for larger deposits—a $100,000 CD might pay 0.25% more than a $10,000 CD. A few banks offer promotional rates for new customers, though those rates usually apply only to the first CD you open.

Before you commit, confirm the bank is FDIC-insured, write down the exact early withdrawal penalty, and check whether interest compounds or pays at maturity. A slightly higher rate doesn't matter if the penalty is steep or if the bank isn't insured. Use a CD calculator (most banks have one on their website) to compare your total earnings across different banks and terms.

Frequently Asked Questions

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

No. A CD is a fixed deposit—you choose the amount when you open it, and you can't add more money to that specific CD. If you want to deposit more, you have to open a separate CD. Some banks let you open multiple CDs at once, each with its own term and rate.

What happens if I need the money before the CD matures?

You can withdraw it, but you'll pay an early withdrawal penalty. The penalty reduces your earnings or principal. Before you withdraw, calculate whether the penalty is worth it—sometimes it's small enough that breaking the CD makes sense, especially if you need the money urgently.

Is a CD better than a savings account?

CDs pay higher interest rates, but you can't access the money without a penalty. A savings account pays less but offers flexibility. If you won't need the money for several months or longer, a CD usually earns more. If you might need it sooner, a high-yield savings account is safer.

Do I have to renew my CD when it matures?

No. When a CD matures, you can withdraw the money, open a new CD, or let it auto-renew into a new CD at the bank's current rate. Check your account around the maturity date—if you don't want to renew, tell the bank before the auto-renewal happens, or you'll be locked in again.

What's the difference between a CD and a money market account?

A CD locks your money for a set term at a fixed rate. A money market account is more like a savings account—you can withdraw anytime, but the rate can change. Money market accounts usually pay more than regular savings but less than CDs. Choose a CD if you want a may provide rate and won't need the money; choose a money market account if you want higher interest with flexibility.