High-yield savings vs a CD
By Jude Wallis
The arithmetic is identical; the certainty is not. A CD fixes the rate for the term, so $10,000 at 4.5 percent APY reaches $12,461.82 after five years. A savings account can be cut whenever the issuer likes, and at an average of 4 percent the same deposit reaches $12,166.53.
| High-yield savings | Certificate of deposit | |
|---|---|---|
| Rate certainty | None. The quoted APY is today's, not the term's. | Full, for the whole term. |
| Access to the money | Any time, usually within a day. | At maturity, or earlier with a penalty in forfeited interest. |
| \$10,000 over five years | $12,166.53 if the rate averages 4 percent. | $12,461.82 at a locked 4.5 percent. |
| What compounds | The balance, at whatever rate applies that month. | The balance, at one rate, for the whole term. |
| Risk it protects against | None. It benefits if rates rise. | Falling rates, which is the whole reason to lock. |
| Suits | An emergency fund, where access is the point. | Money with a known date, where the rate matters more than the flexibility. |
On this page
Same identity, different guarantee
Both products grow a balance by an annual percentage yield, and that is one formula: multiply by one plus the rate, once a year, for as many years as the money stays. At 4.5 percent for five years, $10,000 becomes $12,461.82, of which $2,461.82 is interest.
The difference is what happens to the rate in year two. The CD's is written into the contract. The savings rate is a marketing decision that the bank can revise the week after you deposit, and if it averages 4 percent instead the same $10,000 reaches $12,166.53. That is the price of being able to walk away at any moment.
The lock is the product
An early withdrawal penalty is usually quoted in months of interest, which makes a CD a bet with a known cost of being wrong. Break it early and you keep the principal and lose some of the interest; hold it and the rate that looked ordinary in a falling market turns out to have been the point.
That is why the two are usually held together rather than chosen between. Cash that might be needed this month belongs where access is instant; cash with a date on it can take the fixed rate. Savings account types covers the shapes on offer, and how CD ladders work is the standard way of keeping both properties at once.
Comparing them honestly
Compare APY to APY, not APY to a nominal rate, since APY already contains the compounding. Then ask the second question the headline rate hides: how long is this rate promised for. Five years of certainty at 4.5 percent and an unknown path averaging 4 percent are almost 300 dollars apart on a $10,000 deposit, and the gap grows with the balance. The CD calculator prices the locked side, and the savings goal calculator works backwards from a target instead. This is educational material, not financial advice.
Worked examples
\$10,000 in a five-year CD at 4.5 percent
A $10,000 deposit is placed in a five-year CD paying 4.5 percent APY. What is it worth at maturity?
- Multiply by 1.045 once for each of the five years the money is locked.
- That gives $12,461.82, of which $2,461.82 is interest.
The CD matures at $12,461.82, and the rate was known on day one.
The same deposit in savings at 4 percent
The same $10,000 sits in a savings account whose rate averages 4 percent over the five years. Where does it end?
- Apply the same compounding, one multiplication a year, at 4 percent instead.
- The balance reaches $12,166.53, so interest is $2,166.53.
- Against the locked CD that is of forgone interest.
$12,166.53, a little under the locked CD, in exchange for being able to withdraw at any time.
Common questions
Is a CD always the higher rate?
No. Short CDs sometimes pay less than savings accounts. The lock is what you are buying, not automatically a higher rate.
What does breaking a CD cost?
Typically a stated number of months of interest. The deposit itself is not usually at risk from the penalty.
Are both insured?
Deposit insurance covers both to the same limits at an insured institution. The insurance does not care which product it is.
Is this financial advice?
No. It is educational material comparing a fixed and a variable savings rate.
Keep reading
This page is educational material, not financial advice. The figures come from the formula shown and assume the inputs you enter hold for the whole term. Your own rate, fees, taxes and timing will differ, so treat the output as arithmetic to check a decision against, not as a recommendation.