Savings Calculator
How a high-yield savings account grows with monthly deposits
Last updated: October 2026 · National rate: FDIC national savings rate, September 2026
Your savings
Added at the end of each month
0 = no change
Default: CPI-U, 12 months to September 2026 (BLS)
Balance by year
| Year | APY | Deposits | Interest | Balance | At 0.37% |
|---|---|---|---|---|---|
| 1 | 4.00% | $8,600 | $266 | $8,866 | $8,625 |
| 2 | 4.00% | $12,200 | $686 | $12,886 | $12,263 |
| 3 | 4.00% | $15,800 | $1,267 | $17,067 | $15,914 |
| 4 | 4.00% | $19,400 | $2,015 | $21,415 | $19,579 |
| 5 | 4.00% | $23,000 | $2,937 | $25,937 | $23,258 |
How the projection works
The APY is turned into a monthly rate: (1 + APY)1/12 - 1. Each month the balance earns that rate and then your deposit is added. Over a full year with no deposits, the balance grows by exactly the APY, which is how banks define it.
The comparison column runs the same deposits at the fdic national savings rate, september 2026 of 0.37%. The today's-dollars figure divides the final balance by (1 + inflation)years.
Interest is shown before tax. Savings interest is taxed as ordinary income each year.
Worked example
You open a high-yield account with $5,000 at 4.00% APY and add $300 at the end of every month for 5 years.
- Deposits: $5,000 + 60 x $300 = $23,000.
- Balance after 5 years: $25,936.97, so $2,936.97 is interest.
- At the 0.37% national average rate the same deposits reach $23,257.61.
- With 3.7% inflation, $25,936.97 in 5 years buys what about $21,628 buys today.
Frequently Asked Questions
How much interest will my savings earn?
Multiply by the APY for a single year: $10,000 at 4.00% APY earns $400 in a year. With monthly deposits the math compounds month by month. $5,000 plus $300 a month at 4.00% APY grows to $25,936.97 after 5 years: $23,000 of deposits and $2,936.97 of interest.
What is the average savings account rate right now?
The FDIC national rate for savings accounts was 0.37% in September 2026. It is a deposit-weighted average across all insured banks and credit unions, pulled down by large banks that pay very little. Online high-yield accounts typically pay several times more, so where you keep your cash matters.
Is a high-yield savings account worth it?
For cash you need to keep safe and available, usually yes. In the example above, the same deposits at the 0.37% national rate grow to only $23,257.61, about $2,679 less than at 4.00%. High-yield accounts at FDIC-insured banks carry the same $250,000 per depositor, per bank, per ownership category insurance as any other bank account.
Can a savings account keep up with inflation?
Only if the after-tax rate beats inflation. Consumer prices rose 3.7% in the 12 months to September 2026 (BLS CPI-U). A 4.00% APY taxed at 22% keeps 3.12%, slightly less than that inflation rate, so the purchasing power of the balance shrinks a little. Savings accounts are for safety and access, not long-term growth.
Will my savings rate stay the same?
No. Savings account rates are variable and banks can change them at any time, usually following Federal Reserve rate moves. Use the optional APY change field to see what happens if your rate drops after a year or two. A CD locks in a rate for a fixed term if you want certainty.
Is savings account interest taxable?
Yes. Interest is taxed as ordinary income in the year it is credited, federally and in most states, and your bank sends Form 1099-INT when interest reaches $10 or more. You owe the tax even if you did not receive a form.