Compound interest is one of the most powerful ideas in personal finance. Put simply: you earn interest on your initial deposit, and then you earn interest on that interest. Over time, this "interest on interest" effect can significantly increase your savings compared to simple interest, where you only earn on the original amount.
Simple vs compound interest
With simple interest, a 10% annual rate on 1,000,000 AMD always pays 100,000 AMD per year—only the principal earns. With compound interest, the first year you earn 100,000 AMD and it is added to your balance; the second year you earn 10% on 1,100,000 AMD (110,000 AMD), and so on. Each time the bank pays or credits interest, that amount becomes part of the balance that earns in the next period.
Frequency of compounding
The more often interest is paid and added to the balance, the stronger the compounding effect. Annual payment means one addition per year; quarterly means four; monthly means twelve. So a 10% rate paid monthly will yield slightly more by the end of the year than 10% paid once at the end, because each monthly payment starts earning interest in the following months. Our article on interest payment frequency goes into more detail.
Long-term impact
Over many years, the difference between simple and compound interest becomes large. That is why starting early and leaving money to compound, and adding regular contributions when possible, can build substantial savings. Remember that interest on Armenian bank deposits is subject to 10% tax, so the calculator shows net (after-tax) results. For more on tax, see how deposit interest is taxed in Armenia.
Understanding compound interest helps you set realistic goals and compare deposit products fairly using tools like the Saving.am calculator.