What a Certificate of Deposit Is and How It Works

A certificate of deposit (CD) is a savings product where you give a bank or credit union a lump sum of money for a set period of time, and they pay you a fixed interest rate in return. You agree not to touch that money until the term ends — typically anywhere from three months to five years. In exchange for locking up your cash, the bank pays you more interest than you'd earn in a regular savings account.

The mechanics are straightforward: you deposit money, the bank holds it, and on a set maturity date the bank returns your original deposit plus the interest you've earned. The interest rate is locked in when you open the CD, so you know exactly how much you'll have at the end. If you need the money before the term is up, you can withdraw it, but you'll pay an early withdrawal penalty — usually a few months' worth of interest.

CDs are insured by the Federal Deposit Insurance Corporation (FDIC) if held at a bank, or by the National Credit Union Administration (NCUA) if held at a credit union, up to $250,000 per account. This means your money is protected even if the institution fails.

Key Takeaways

  • You deposit a fixed amount, agree to leave it untouched for a set term, and receive a may provide interest rate that does not change.
  • The interest rate on a CD is typically higher than a savings account because you're committing to lock up your money for months or years.
  • Withdrawing money before the maturity date triggers an early withdrawal penalty, usually several months of interest.
  • Your CD is protected up to $250,000 by federal insurance, whether held at a bank or credit union.
  • Interest can be paid to you monthly, quarterly, or at maturity, depending on the CD and the bank's terms.

How Interest Rates and Terms Are Set

Banks set CD interest rates based on what the Federal Reserve is doing with short-term rates and what other banks are offering. When the Fed raises rates, CD rates typically go up within weeks. When the Fed cuts rates, CD rates fall. You won't see a bank offering 5% on a one-year CD if competitors are offering 4.5% — they'd lose customers.

The term length you choose affects the rate. A three-month CD will pay less than a five-year CD because the bank can't use your money for as long. Longer terms carry more risk for you (you're locked in longer), so banks compensate with higher rates. The tradeoff is yours to make: take a lower rate for quick access to your money, or commit longer for better returns.

Some banks offer variable-rate CDs, where the rate can change during the term, though these are less common. Most CDs are fixed-rate, meaning what you see when you open it is what you get.

Early Withdrawal Penalties and When They Apply

If you close a CD before the maturity date, the bank deducts an early withdrawal penalty from your interest earnings or principal. The penalty amount varies by bank and by term length. A three-month CD might have a penalty of one month's interest, while a five-year CD might have a penalty of six months' interest. Some banks charge a flat dollar amount instead.

The penalty is calculated based on the interest rate you locked in, not the current rate. So if you opened a 5% CD and rates have since dropped to 3%, you still lose interest at the 5% rate. This is how banks protect themselves from losing money on the deal.

A few banks offer no-penalty CDs, which let you withdraw early without a penalty — but the interest rate is lower to compensate. These make sense if you're uncertain whether you'll need the money, but you're trading yield for flexibility.

How Interest Payments Work

Interest on a CD can be paid to you in different ways depending on the bank. Some banks pay interest monthly or quarterly, depositing it into a linked account or back into the CD itself. Others hold all the interest until maturity and pay it as a lump sum. A few banks let you choose.

If interest is deposited back into the CD, it compounds — meaning you earn interest on your interest. This slightly increases your total return, though the effect is small on short terms. If interest is paid out to another account, you can spend it or reinvest it elsewhere.

The bank will send you a 1099-INT form at tax time if your CD earned $10 or more in interest. You owe federal income tax on that interest in the year it was earned, even if you didn't withdraw the money yet.

CD Ladders and How to Use Them

A CD ladder is a strategy where you open multiple CDs with different maturity dates instead of putting all your money into one CD. For example, you might open five one-year CDs, each maturing in years one through five. As each CD matures, you can reinvest it at the current rate or use the money.

Laddering solves two problems: it gives you regular access to portions of your money without penalties, and it lets you take advantage of rate changes. If rates rise, you reinvest the maturing CD at the higher rate. If rates fall, you're protected because part of your money is still locked in at the old rate.

A ladder works best when you have a lump sum to invest and don't need all of it right away. If you only have $5,000, a ladder might not be practical because you'd split it into small pieces. If you have $50,000, you could open five $10,000 CDs and have one mature each year.

CDs Versus Savings Accounts and Money Market Accounts

A regular savings account offers flexibility — you can withdraw money anytime without penalty — but the interest rate is usually much lower, often under 0.5%. A CD locks you in but pays significantly more, sometimes two to three times as much depending on the term and current rates.

A money market account sits between the two. It typically pays more than a savings account but less than a CD, and it gives you limited check-writing or debit card access while still requiring you to maintain a minimum balance. You can withdraw money, but there are limits on how often.

Choose a CD if you have money you won't need for several months or longer and want the highest may provide return. Choose a savings account if you need quick access and are willing to accept lower interest. A money market account works if you want something in the middle.

What Happens When Your CD Matures

On the maturity date, your CD stops earning interest. The bank will notify you before this happens, usually 30 days in advance, and give you options. You can roll the money into a new CD at the current rate, move it to a savings account, or withdraw it entirely. Some banks automatically roll CDs into new ones at the current rate if you don't tell them otherwise — read the fine print to know your bank's policy.

If you don't act and the bank auto-renews, you're locked in again for another term at whatever the new rate is. If rates have dropped significantly, this might not be what you want. Set a reminder on your phone or calendar for a week before maturity so you have time to decide.

If you withdraw the money at maturity, there's no penalty. The bank will report the interest on a 1099-INT if it's $10 or more, and you'll owe taxes on it.

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 that's what stays in the account. If you want to invest more money, you'd need to open a separate CD. Some banks offer "add-on CDs" that let you deposit more during the term, but these are uncommon and usually have lower rates.

What if I need the money before the CD matures?

You can withdraw it, but you'll pay an early withdrawal penalty. The penalty is usually several months of interest, so you might come out behind compared to what a savings account would have paid. Before withdrawing, call the bank and ask exactly what the penalty will be — it's calculated based on your rate and term, and knowing the number helps you decide if it's worth it.

Are CDs a good investment right now?

That depends on current interest rates and what you're comparing them to. When CD rates are high (typically when the Federal Reserve has raised rates), CDs can be competitive with bonds and stock market returns for the short term. When rates are low, the returns are modest. CDs are best for money you know you won't need and want to keep safe, not for money you're trying to grow aggressively.

Do I have to pay taxes on CD interest?

Yes. Interest earned on a CD is taxable income in the year it was earned, whether you withdrew it or not. The bank sends you a 1099-INT form if interest is $10 or more. You report this on your tax return and pay federal income tax at your ordinary rate, plus state income tax if your state has one.

What's the difference between a bank CD and a credit union CD?

The mechanics are the same — you deposit money for a term and earn a fixed rate. Credit union CDs are insured by the NCUA instead of the FDIC, but both offer the same $250,000 protection. Credit unions sometimes offer slightly higher rates than banks, but this varies. Shop both to compare.