Daily vs Monthly Compound Interest

Daily vs monthly vs annual compounding

Compounding frequency controls how often interest is calculated and added to the balance. The more frequently interest is added, the more often new interest can start earning interest itself.

At the same annual rate, daily compounding normally produces a little more than monthly compounding, and monthly compounding normally produces a little more than annual compounding.

Example: £10,000 at 5% for 10 years

This table compares the same starting amount and rate using different compounding frequencies.

Compare monthly compounding in the calculator or open daily compounding.

Why the difference can be small

People often expect daily compounding to be dramatically better than monthly compounding. In reality, if the same annual rate is used, the difference is usually much smaller than the difference caused by changing the rate, the time period or the regular contribution amount.

When compounding frequency matters most

• When comparing products with similar quoted rates.
• When modelling long time periods.
• When balances are large enough for small percentage differences to become meaningful.
• When comparing loans or debts where compounding can work against you.

Best default for estimates

If you do not know the exact compounding frequency, monthly compounding is often a useful default for savings and investment-style estimates. For product-specific calculations, use the frequency stated in the terms.