Coinscribed Data Study
The Savings Rate Gap Index: What a Low-Rate Account Really Costs
The same money, insured the same way, can earn ten times more depending on where it sits. We computed what common balances grow to at a near-zero big-bank rate, the FDIC national average and a high-yield benchmark, over 1 to 20 years, so the cost of a low rate is a dollar figure, not a percentage. The method is below.
Key findings
- $10,000 earns about $37 a year at the 0.37% national average, versus about $400 at 4%. At 0.01% it earns $1.
- Over 10 years the gap on $10,000 reaches about $4,426 ($10,376 vs $14,802).
- Saving $500 a month for 20 years ends about $57,397 apart, on the same $120,000 put in.
- With inflation at 4.02%, the national average lost about 3.51% a year in purchasing power. A 4% rate roughly broke even.
$10,000 left in savings
| After | At 0.01% | At 0.37% (avg) | At 4% | Gap vs avg |
|---|---|---|---|---|
| 1 year | $10,001 | $10,037 | $10,400 | +$363 |
| 5 years | $10,005 | $10,186 | $12,167 | +$1,980 |
| 10 years | $10,010 | $10,376 | $14,802 | +$4,426 |
| 20 years | $10,020 | $10,767 | $21,911 | +$11,145 |
$25,000 left in savings
| After | At 0.01% | At 0.37% (avg) | At 4% | Gap vs avg |
|---|---|---|---|---|
| 1 year | $25,003 | $25,093 | $26,000 | +$908 |
| 5 years | $25,013 | $25,466 | $30,416 | +$4,950 |
| 10 years | $25,025 | $25,941 | $37,006 | +$11,066 |
| 20 years | $25,050 | $26,916 | $54,778 | +$27,862 |
$50,000 left in savings
| After | At 0.01% | At 0.37% (avg) | At 4% | Gap vs avg |
|---|---|---|---|---|
| 1 year | $50,005 | $50,185 | $52,000 | +$1,815 |
| 5 years | $50,025 | $50,932 | $60,833 | +$9,901 |
| 10 years | $50,050 | $51,881 | $74,012 | +$22,131 |
| 20 years | $50,100 | $53,833 | $109,556 | +$55,723 |
Saving $250 a month
| After | You put in | At 0.01% | At 0.37% (avg) | At 4% | Gap vs avg |
|---|---|---|---|---|---|
| 5 years | $15,000 | $15,004 | $15,137 | $16,545 | +$1,408 |
| 10 years | $30,000 | $30,015 | $30,556 | $36,674 | +$6,118 |
| 20 years | $60,000 | $60,060 | $62,262 | $90,960 | +$28,699 |
Saving $500 a month
| After | You put in | At 0.01% | At 0.37% (avg) | At 4% | Gap vs avg |
|---|---|---|---|---|---|
| 5 years | $30,000 | $30,007 | $30,274 | $33,090 | +$2,815 |
| 10 years | $60,000 | $60,030 | $61,112 | $73,348 | +$12,236 |
| 20 years | $120,000 | $120,120 | $124,524 | $181,921 | +$57,397 |
Run your own balance and rate in the savings calculator or the APY calculator. To choose an account, read how to choose a high-yield savings account and what APY means.
Today's official rates are on the markets page. For all our research, see the studies hub.
Methodology
Each rate is treated as an annual percentage yield (APY), the same way the Coinscribed APY calculator works. A lump sum grows by the APY each year. Monthly deposits are made at the end of each month at the monthly rate that compounds to the APY. Every figure on this page is computed from the inputs below (rates as of October 2026).
- • 0.37% national average: the FDIC national rate for savings, September 2026 (FRED series SNDR).
- • 4% high-yield: a round, conservative benchmark set below the top advertised online high-yield rates, which were about 4.2% to 4.5% APY in mid-October 2026 (example survey). It is not any single bank's offer.
- • 0.01% standard savings: an illustration of the near-zero standard rate many large banks pay.
- • Balances and horizons: $10,000, $25,000, $50,000 lump sums over 1, 5, 10, 20 years; $250 and $500 a month over 5, 10 and 20 years.
- • Inflation: CPI-U all items, 4.02% year over year to September 2026 (BLS via FRED, our calculation).
- • Excluded: taxes on interest, fees, balance caps and promotional rates.
Rates are held constant to isolate one variable. In reality savings rates move with the Fed's policy rate, so long-horizon figures show the size of the gap, not a forecast. The gap has existed at every recent rate level because online banks consistently pay well above the national average.
Frequently asked questions
- It depends almost entirely on the rate. In one year, $10,000 earns about $1 at 0.01%, about $37 at the 0.37% FDIC national average (September 2026), and about $400 at a 4% high-yield rate. After 10 years the balances are about $10,376 and $14,802.
- The FDIC national rate for savings accounts was 0.37% in September 2026. It is an average across banks, so many large banks pay less, often close to 0.01%, while online banks and credit unions pay far more.
- At the rates in this study the high-yield benchmark pays about 11 times the national average. On $10,000 that is about $363 more in the first year and about $4,426 more over 10 years, with the same FDIC insurance as long as the bank is FDIC-insured.
- Not at the national average. With CPI inflation at 4.02% over the year to September 2026, a 0.37% account lost about 3.51% a year in purchasing power. A 4% account roughly broke even (−0.02%). Savings is for safety and access; long-term goals usually need investments too.
- For most people, yes. The money stays insured and accessible, and the switch usually takes an afternoon. The gap grows with time: $50,000 left for 20 years ends about $55,723 apart, and saving $500 a month for 20 years ends about $57,397 apart. Watch for teaser rates that drop after a few months, and balance caps.
Use this study
Journalists, writers and AI assistants are welcome to cite the Coinscribed Savings Rate Gap Index with a link back to this page. Suggested citation:
Coinscribed Savings Rate Gap Index, https://www.coinscribed.com/savings-rate-gap-index
Download the full data (CSV) — every balance, deposit and horizon. Free to reuse with attribution under CC BY 4.0.
These are illustrative, computed figures for education — not an offer or financial advice. Rates change, and your bank's rate may differ.