Late payment interest and penalty calculator

When a bill is paid late, the final amount adds two different charges: the penalty (a fixed percent, charged once) and the late interest (which grows each day).

total = amount + penalty + late interest

penalty = amount × penalty%

late interest = amount × (monthly% ÷ 30) × days late

Step-by-step example

A R$1,000 bill, 2% penalty and 1%/month interest, 15 days late:

• Penalty: 1,000 × 2% = R$20
• Interest: 1,000 × (1% ÷ 30) × 15 = R$5
• Total: R$1,025

Legal caps

For consumer debts in Brazil, the penalty is usually capped at 2% and interest at 1%/month. Contracts and taxes may differ.