Emergency funds, compound growth and getting a savings habit to stick.
Two things do most of the work in saving: how much goes in, and how long it stays. Compound growth is non-linear — the fourth decade of a balance earns many times what the first does — but over the five-to-ten-year horizon most goals actually have, the size of the regular deposit matters more than the rate. An emergency fund comes before both.
Written for the United States. Terminology, protection limits and regulators differ between markets, so a guide from another country will not transfer cleanly.
Compound interest is interest earning interest. The mechanism is simple, the effect is not linear, and it works against you on debt exactly as it works for you on savings.
What an emergency fund is for, how to size one for your situation, and why the account you keep it in matters more than the rate it pays.
Turning a vague intention into a monthly number with a date attached — and deciding what order to fund competing goals in.
Calculators
Run the numbers on your own situation.
What will my savings grow to?
How much do I need to save each month?