A certificate of deposit is a savings account where you lock up your money for a set time in exchange for a higher interest rate

When you open a CD, you give a bank or credit union a lump sum of money — say $5,000 — and agree not to touch it for a specific period. That period might be three months, one year, five years, or longer, depending on the CD you choose. In return, the bank pays you a fixed interest rate that is almost always higher than what you would earn in a regular savings account. At the end of the term, you get your original money back plus all the interest it earned.

The trade-off is simple: you give up access to your cash for a while, and the bank rewards you for that commitment. If you need the money before the term ends, you can withdraw it, but you will pay an early withdrawal penalty — usually a few months' worth of interest. That penalty is why CDs work best for money you know you will not need soon.

Key Takeaways

  • You deposit a fixed amount of money for a fixed time period and receive a may provide interest rate that does not change.
  • The longer the term, the higher the rate — a five-year CD typically pays more than a one-year CD at the same bank.
  • Withdrawing money early triggers a penalty that reduces your earnings, so CDs suit money you will not need for months or years.
  • Your deposit is insured up to $250,000 by the FDIC (at banks) or NCUA (at credit unions), so your principal is protected even if the institution fails.

How interest rates and terms work together

CD rates change based on two things: how long you lock your money away, and what the broader interest rate environment is doing. Banks set their own rates, so a three-month CD at one bank might pay 4.5 percent while another pays 4.2 percent. You can shop around and compare.

The relationship between term length and rate is usually predictable: longer terms pay higher rates. A one-year CD might pay 4.0 percent, while a five-year CD at the same bank pays 4.8 percent. The bank is paying you more because you are committing your money for longer and giving up more flexibility. When interest rates in the broader economy are falling, locking in a longer term can protect you — you keep your rate even as new CDs pay less. When rates are rising, a shorter term lets you reinvest at a higher rate sooner.

What happens when your CD matures

On the maturity date — the day your term ends — the bank automatically returns your principal plus all earned interest to your account. You then have a choice window, usually a few days to a couple of weeks, to decide what to do next. You can withdraw the money, move it to a savings account, or roll it into a new CD.

If you do nothing during that window, most banks will automatically renew your CD into a new term at whatever rate they are currently offering. That new rate might be higher or lower than what you just earned. To avoid being locked in at an unfavorable rate, mark your maturity date on your calendar and decide in advance whether you want to renew, withdraw, or move your money elsewhere.

Early withdrawal penalties and when they apply

If you need your money before the maturity date, you can get it — but the bank will charge you a penalty. That penalty is usually expressed as a number of months of interest. A CD with a three-month interest penalty means you lose three months' worth of the interest you would have earned. On a $10,000 CD paying 4.5 percent annually, that is roughly $112.50 in lost interest.

The penalty is deducted from your interest earnings first. If your interest earnings are not large enough to cover the full penalty, the bank takes the difference from your principal. This is rare with short-term CDs but can happen if you withdraw very early from a long-term CD. Before you open a CD, ask the bank what the early withdrawal penalty is — it varies by institution and by term length.

Comparing CDs to other savings options

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 percent. A money market account sits in the middle: it pays more than savings but less than a CD, and you can withdraw money, though there are limits on how often.

A CD makes sense if you have money you will not need for at least several months and you want to maximize what you earn on it. If you might need the money sooner, or if you want to keep adding to your savings regularly, a high-yield savings account is usually a better fit. If you are saving for something specific with a known date — a down payment in two years, a home repair fund for next spring — a CD with a matching term locks in your rate and removes the temptation to spend the money.

How your CD is protected

Your CD is insured by the FDIC (Federal Deposit Insurance Corporation) if you opened it at a bank, or by the NCUA (National Credit Union Administration) if you opened it at a credit union. That insurance covers up to $250,000 per depositor, per institution. If the bank fails, you get your money back — principal and accrued interest — up to that limit.

The insurance applies to each account separately, so if you have a CD and a savings account at the same bank, they are each covered up to $250,000. If you want to insure more than $250,000, you can open CDs at different banks. The FDIC website has a calculator that shows you exactly how much of your money is covered at any given institution.

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 is what earns interest for the entire term. If you want to save more, you open a separate CD or use a savings account. Some banks offer "add-on CDs" that let you deposit more during the term, but these are uncommon.

What if interest rates go up after I buy a CD?

Your rate stays the same for the entire term — that is the point of a fixed rate. If rates rise, you are locked in at the lower rate. When your CD matures, you can open a new one at the higher rate. This is why shorter-term CDs can be useful in a rising-rate environment.

Is there a minimum amount I have to deposit?

Most banks require a minimum deposit to open a CD, often $500 to $2,500, though some have no minimum. Online banks sometimes offer lower minimums than brick-and-mortar branches. Check the specific bank's requirements before you apply.

Do I have to pay taxes on CD interest?

Yes. CD interest is taxable income in the year you earn it. The bank will send you a 1099-INT form at tax time showing how much interest you earned. You report this on your tax return just like any other interest income.

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 or paying the early withdrawal penalty. The interest rate on the loan is usually a few percentage points above what your CD is earning, but you keep earning interest on the CD itself.