What does 15% per month actually compound to?
Taken at face value and multiplied out, 15% per month is 435% a year. That is about 109x what you would get from a three-month Treasury bill that pays around 4% and a government-insured deposit around 3.5%. The arithmetic below assumes every payment arrives on time, which is the assumption that fails in practice, not the compounding.
A textbook scheme profile
Rates in this range do not describe investing, they describe a Ponzi structure: the payout schedule only clears while new deposits keep arriving.
15% per month, by starting amount
| Held for | $100 becomes | $1,000 becomes | $10,000 becomes |
|---|---|---|---|
| 1 year | $535.03 | $5.4K | $53.5K |
| 3 years | $15.3K | $153.2K | $1.5M |
| 5 years | $438.4K | $4.4M | $43.8M |
| 10 years | $1.9B | $19.2B | $192.2B |
Balance = principal x (1 + 15%) ^ periods, compounded every month.
15% per month against what is guaranteed
Reference levels: long-run approximations, October 2026. A multiple of "-" means the comparison does not apply.
| Reference level | Rate | This rate in multiples |
|---|---|---|
| Insured bank deposit (US, FDIC) | 3.5% a year (guaranteed) | 124x |
| 3-month US Treasury bill | 4.0% a year (guaranteed) | 109x |
| US inflation (consumer prices) | 2.5% a year (not investable, measures erosion) | 174x |
| S&P 500, long-run average | 10.0% a year (not guaranteed to anyone) | 43.5x |
| Best long-run professional record (Buffett, decades) | 20.0% a year (not guaranteed to anyone) | 21.8x |
The red line
A guaranteed return higher than a Treasury bill or an insured deposit cannot exist. Every dollar paid above the risk-free rate is paid for with risk, leverage, or other people's deposits. A published promise of a fixed return above the risk-free rate is the definition of a return trap.
No published entry on this register currently quotes a rate in this range. The arithmetic above still applies to any offer that does.
Questions about 15% per month
- What is 15% per month as an annual return?Compounded, 15% per month is 435% a year. Interest is multiplied, not added, so the yearly figure is (1 + 15/100) raised to the power of 12, minus one.
- How long would 15% per month take to double my money?About 5 days. At a monthly rate that high the balance reaches a million dollars from a thousand in 2 months, which is why the number is only ever advertised, never audited.
- Is 15% per month realistic?No supervised product guarantees anything close. A monthly percentage is quoted because it sounds small, but 435% a year is far above an insured deposit, above a Treasury bill, and above the best long-run professional record. A fixed promise at that level has to be paid from someone else's deposit.
Try your own numbers
- Daily return calculator — your amount, your horizon.
- Guaranteed return check — is any of this guaranteed?
- Where the payout comes from — how many new depositors it takes.
- Loss recovery — what one bad month costs.
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