Compounding: Why Starting Early Beats Saving More

Compounding is the one piece of financial mathematics that genuinely surprises people, because the shape of the curve does not match intuition.

Run the numbers

Put $500 a month into an account averaging 7%:

• After 10 years: roughly $86,000
• After 20 years: roughly $260,000
• After 30 years: roughly $610,000

You contributed $60,000, $120,000 and $180,000 respectively. So the first decade returns about $26,000 in growth. The third decade alone returns about $350,000.

What that means in practice

The money you invest in your twenties does more work than the money you invest in your forties — not slightly more, several times more. Every year you delay removes a year from the far end of the curve, which is the expensive end.

Someone investing $200 a month starting at 25 typically ends up ahead of someone investing $400 a month starting at 40.

The order of operations

Before you optimise which fund to buy, get the sequence right:

• Employer match — an immediate 50–100% return
• High-interest debt — a guaranteed return equal to the rate
• Tax-advantaged accounts — 401(k), IRA
• Taxable brokerage — everything after that

Following the order matters far more than picking the right fund. Most of the gap between outcomes comes from sequence and consistency, not selection.