Savings Calculator: Grow a Bank Savings Balance
Estimate how a bank savings balance builds up from regular monthly deposits and the modest interest a deposit account pays.
Adjust the inputs and select Calculate for a full breakdown.
Year-by-year growth schedule
Compare Common Scenarios
How the numbers shift across typical situations for this calculator:
| Scenario | Future value | Total contributions | Total interest earned |
|---|---|---|---|
| $2k · $150/mo · 0.41% · 5yr | $11,132.73 | $11,000.00 | $132.73 |
| $5k · $300/mo · 1.78% · 5yr | $24,275.77 | $23,000.00 | $1,275.77 |
| $1k · $200/mo · 4.0% · 10yr | $30,940.79 | $25,000.00 | $5,940.79 |
| $10k · $0/mo · 0.41% · 3yr | $10,123.74 | $10,000.00 | $123.74 |
How This Calculator Works
Enter your current balance, the account's annual percentage yield, how long you plan to keep saving, and your monthly deposit. The calculator credits interest monthly and adds your deposit, then shows the running balance. Because deposit rates are low, the schedule makes plain how much of the total is your own money rather than interest.
The Formula
Future Value with Regular Contributions
P = starting amount, PMT = monthly contribution, r = monthly rate (annual ÷ 12), n = number of months
Worked Example
With $2,000 already saved, $150 added each month, and a 0.41% rate over 5 years, the balance reaches about $11,133. You deposited $11,000 of that yourself, so interest contributed only around $133 — a result typical of a standard savings account.
Key Insight
At ordinary savings rates, interest is almost a rounding error next to your deposits. The real lever is the deposit habit — and moving to a high-yield account or a CD can multiply the interest portion several times over without adding any risk.
High-yield savings vs traditional bank: the 4-5% gap that's free money
Top high-yield savings accounts (HYSA) in 2026 offer 4-5% APY: Ally Bank, Marcus by Goldman Sachs, Discover Online Savings, Capital One 360 Performance Savings, Wealthfront Cash Account. Traditional brick-and-mortar bank savings: typically 0.01-0.50% APY. The gap is roughly 4-4.5 percentage points.
Concrete annual difference: $50,000 in a 4.5% HYSA earns $2,250/year. Same $50,000 in a 0.05% Chase Savings: $25/year. Annual difference: $2,225 — equivalent to a 4.5% annual raise on $50k of savings, for zero risk, zero work beyond an account-opening 15 minutes.
All FDIC-insured banks are equally safe up to $250,000 per depositor per bank. Online banks are NOT 'less safe' than physical banks — they have the same FDIC backing. The interest rate gap reflects business model: online banks have lower overhead (no branches, fewer employees) and pass savings to depositors. Move emergency fund + cash savings to HYSA immediately; the only reason not to is inertia.
Money market funds: the broker's HYSA equivalent
Money market funds (MMFs) at brokerages offer similar yields to HYSAs but with slightly different structure. Examples: Vanguard Federal Money Market (VMFXX, ~5% yield), Fidelity SPRXX (~5%), Schwab Value Advantage Money Fund (SWVXX, ~5%). These are mutual funds that invest in very short-term Treasury bills and high-quality commercial paper.
Key differences from HYSA: (1) not FDIC-insured but SIPC-insured up to $500,000 per broker. SIPC protects against broker failure, not investment losses (though MMFs rarely 'break the buck' below $1.00 — only happened twice in history during 2008 and 2020 crises). (2) Yields often slightly higher than HYSAs (5% vs 4.5% in 2026). (3) Redemption usually 1-3 days (vs same-day for HYSA).
Practical use: keep ~3 months of emergency fund in HYSA (immediate access), 3-6 more months in MMF at brokerage (slightly higher yield, slightly slower access). For amounts beyond $250k per bank (FDIC limit), splitting between MMFs and multiple banks ensures both yield optimization and full protection.
When to leave cash vs invest: the right amount of dry powder
Common mistake: holding too much in cash 'just in case the market drops'. Historical data: stocks beat cash in 70% of 1-year periods, 85% of 5-year periods, 95% of 20-year periods. The opportunity cost of excess cash is real and compounding.
Right cash amounts by life stage: (1) Early career (20s-30s): emergency fund + maybe 1-3 months extra. EVERYTHING else into long-horizon investments. Time is on your side. (2) Mid-career (30s-50s): emergency fund + planned major expenses (down payment, major repair, kids' upcoming college). 5-10% of total assets is typical. (3) Pre-retirement (5-10 years out): build up to 1-3 years of expenses in cash to weather a market crash in early retirement years. (4) Retirement: 2-5 years of essential expenses in cash + bonds laddered for income.
Counter-intuitive truth: 'cash sitting on the sidelines waiting for a market drop' often misses the recovery. Studies show that long-term wealth depends more on TIME in market than TIMING the market. Set a savings target appropriate to your stage, hit it, then put the rest in long-term investments — don't accumulate dry powder hoping to catch the bottom.
Savings interest earned by APY (annual, no withdrawals)
Annual interest earned on common savings balances at different rates. Shows the dramatic difference between traditional bank and high-yield options.
| Balance | 0.05% (typical brick-and-mortar) | 2.5% (decent HYSA) | 4.5% (top HYSA 2026) | 5.0% (top MMF 2026) |
|---|---|---|---|---|
| $10,000 | $5 | $250 | $450 | $500 |
| $25,000 | $13 | $625 | $1,125 | $1,250 |
| $50,000 | $25 | $1,250 | $2,250 | $2,500 |
| $100,000 | $50 | $2,500 | $4,500 | $5,000 |
| $250,000 | $125 | $6,250 | $11,250 | $12,500 |
FDIC-insured up to $250k per depositor per bank. SIPC-insured MMFs up to $500k per broker. For larger balances, split across multiple banks (or use cash-management accounts that automate FDIC sweep across partner banks for $1M+ insurance).
Frequently Asked Questions
What does APY mean?
Annual percentage yield is the rate a deposit account earns once compounding is included. It is the figure to compare between accounts because it already reflects how often interest is credited.
Is my savings balance insured?
Deposits at an FDIC-member bank are insured up to the standard limit per depositor, per ownership category. That protection is why a savings account is considered a safe place to keep cash.
Why is the interest I earn so small?
Standard savings accounts pay very little. Almost all balance growth comes from your own deposits unless you switch to a high-yield account or lock funds into a certificate of deposit.
Should I use a CD instead?
A certificate of deposit usually pays more than a savings account in exchange for leaving the money untouched for a fixed term. The cited CD benchmark shows the current gap; weigh it against needing access to the cash.
How much should I save each month?
A common starting point is enough to build three to six months of expenses as an emergency fund, then to keep going for shorter-term goals. The monthly deposit field lets you test what a habit produces.
References & Authoritative Sources
- FDIC — Federal Deposit Insurance Corporation — Deposit Insurance limits and rules · consulted May 31, 2026 · Federal regulator — $250k per depositor per ownership category per bank
- SEC — U.S. Securities and Exchange Commission — Money market fund regulations · consulted May 31, 2026 · Securities regulator — MMF disclosure rules, NAV maintenance, liquidity requirements
- Federal Reserve — H.6 Money Stock Measures — Money market fund assets · consulted May 31, 2026 · Authoritative source for US money market fund industry statistics
Related Calculators
Data Sources & Benchmarks
This calculator draws on 3 independent, dated sources. The starting values for savings rate (apy) are taken from the benchmarks below and refresh whenever the snapshots are updated.
Methodology & Review
Balances are compounded monthly at a fixed annual percentage yield with a constant monthly deposit. The model assumes the rate holds steady; in practice variable savings rates move with the broader interest-rate environment.
Written by Ugo Candido · Last updated May 17, 2026.