What happens when you open a CD

When you open a certificate of deposit, you give the bank a lump sum of money and agree to leave it untouched for a set period—called the term. In exchange, the bank pays you a fixed interest rate, usually higher than a regular savings account. You cannot withdraw the money before the term ends without paying a penalty, which is why banks can afford to offer you more interest.

The bank uses your money during that term. They lend it out, invest it, or use it to fund their operations. You are essentially lending to the bank, and the interest rate is what they pay you for that loan. The rate is locked in on the day you open the CD—it does not change, even if the bank's rates go up or down later.

CDs come in different term lengths: 3 months, 6 months, 1 year, 2 years, 5 years, or longer. The longer the term, the higher the interest rate usually is, because you are committing your money for a longer time. A 5-year CD typically pays more than a 1-year CD at the same bank.

Key Takeaways

  • You deposit money into a CD for a fixed term (3 months to 5 years or more) and receive a locked-in interest rate that does not change.
  • Your money is insured up to $250,000 per depositor, per bank, by the FDIC, so your principal is protected even if the bank fails.
  • Withdrawing money before the term ends triggers an early withdrawal penalty, which reduces your earnings and sometimes your principal.
  • When the term ends, your CD matures and you can withdraw the money plus interest, renew it for another term, or move it elsewhere.
  • CD rates vary by bank and term length, so comparing offers across banks before you open one can mean hundreds of dollars in extra interest.

How interest accrues and compounds on a CD

The interest rate on your CD is expressed as an annual percentage yield (APY). This is the actual return you will earn in one year, including the effect of compounding. If a CD has a 4.5% APY and you deposit $10,000, you will earn roughly $450 in interest over 12 months (the exact amount depends on how the bank compounds interest—daily, monthly, or at maturity).

Most banks compound interest daily or monthly, meaning they calculate interest on your principal plus any interest already earned. Compounding happens automatically; you do not have to do anything. The more frequently interest compounds, the slightly more you earn, though the difference is usually small.

For terms shorter than one year, the interest is prorated. A 6-month CD at 4.5% APY will pay you roughly half of what a 12-month CD would pay, because your money is earning interest for only half the year. The bank calculates this automatically and credits the interest to your account at maturity.

What happens when your CD reaches maturity

When your term ends, your CD matures. The bank adds all accrued interest to your account and the CD stops earning. You now have several options: withdraw the money, renew the CD for another term at the current rate, or move it to a different product.

Banks typically give you a grace period—usually 7 to 10 days—after maturity to decide what to do. If you do nothing during that window, many banks automatically renew your CD for the same term at whatever rate they are currently offering. Check your CD agreement or call your bank to confirm their renewal policy, because the new rate may be lower than what you earned before.

If you want to withdraw your money, you can do so without penalty once the CD has matured. The funds usually appear in your linked checking or savings account within one to two business days. If you want to move the money to a different bank, you can request a check or wire transfer.

Early withdrawal penalties and how they work

If you withdraw money before your CD matures, the bank charges an early withdrawal penalty. The penalty amount varies by bank and by term length. A typical penalty for a 1-year CD might be 3 to 6 months of interest; for a 5-year CD, it might be 6 to 12 months of interest.

The penalty is deducted from your interest earnings first. If you have earned enough interest to cover it, you lose some or all of your earnings but keep your principal. If you have not earned enough interest yet—for example, you withdraw after 2 months of a 1-year CD—the penalty eats into your principal, and you get back less than you deposited.

Some banks offer no-penalty CDs or CD ladders as alternatives. A no-penalty CD lets you withdraw without a penalty, but the interest rate is usually lower. A CD ladder means you open multiple CDs with different maturity dates so that part of your money matures every few months, giving you regular access without penalties.

FDIC insurance protects your CD deposit

Your CD is insured by the Federal Deposit Insurance Corporation (FDIC) up to $250,000 per depositor, per bank. This means if your bank fails, the FDIC will reimburse you for your full CD balance and accrued interest, up to that limit. Your principal is safe regardless of what happens to the bank.

The $250,000 limit applies per bank, not per CD. If you have multiple CDs at the same bank, the total coverage is $250,000 across all of them. If you want to insure more than $250,000, you can open CDs at different banks; each bank's coverage is separate.

Credit unions offer a similar protection called NCUA insurance (National Credit Union Administration), also up to $250,000 per member, per institution. If you are opening a CD at a credit union, confirm it is NCUA-insured.

Comparing CD rates and terms across banks

CD rates change frequently and vary significantly between banks. A large national bank might offer 4.0% APY on a 1-year CD, while an online bank offers 4.8% on the same term. Over one year, that 0.8% difference means $80 more in interest on a $10,000 deposit.

Online banks and credit unions often offer higher rates than brick-and-mortar banks because they have lower overhead costs. However, some people prefer the in-person service of a local branch. The trade-off is usually worth calculating: if you are depositing $50,000, a 0.5% rate difference equals $250 per year.

Before you open a CD, check rates at several banks using their websites or a rate-comparison tool. Write down the APY, the term, and any special conditions (like minimum deposit amounts). Also confirm the early withdrawal penalty, because a higher rate is less attractive if the penalty is steep.

Tax treatment of CD interest

Interest you earn on a CD is taxable income. The bank will send you a Form 1099-INT in January of the following year showing how much interest you earned. You must report this on your federal tax return, even if the interest was not paid out to you in cash.

The interest is taxed at your ordinary income tax rate, which is usually higher than the capital gains rate. This means a 4.5% CD earning $450 might cost you $100 to $150 in federal taxes, depending on your tax bracket. Some people open CDs in tax-advantaged accounts like IRAs to avoid this, though contribution limits apply.

If you withdraw money early and pay a penalty, you cannot deduct the penalty from your taxable interest. You still owe tax on the full amount of interest earned, even though you paid a penalty to get your money out.

Frequently Asked Questions

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

No. A CD is a fixed deposit—you cannot add to it or withdraw from it without triggering the early withdrawal penalty. If you want to deposit more money, you must open a separate CD. Some banks let you open multiple CDs at once with different terms, which is called a CD ladder.

What if I need my money before the CD matures?

You can withdraw it, but you will pay an early withdrawal penalty. Calculate whether the interest you have earned so far minus the penalty is worth it. If you have only earned $50 in interest but the penalty is $100, you lose money. If you think you might need the money, consider a shorter-term CD or a no-penalty CD instead.

Is a CD better than a savings account?

CDs usually pay more interest because you commit to leaving the money alone. A savings account is more flexible—you can withdraw anytime without penalty. If you have money you will not need for several months or years, a CD typically 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 your CD matures, you can withdraw the money, move it to another bank, or let it renew. If you do nothing, most banks automatically renew at their current rate, which may be lower. Read your maturity notice carefully so you know the deadline to make a choice.

What happens to my CD if the bank is sold or merges?

Your CD stays in force under the same terms. The new bank or merged entity must honor your rate and maturity date. Your FDIC insurance continues to apply. You will receive notice of the change and information about how to access your account with the new institution.