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⏳ Freelance & Small Business · Tool #29

Late Payment Calculator

Calculate simple late-payment interest and the total amount due after a payment delay.

Enter your business figures

Enter the figures below to calculate your result.

Currency selection changes only the displayed symbol. No exchange-rate conversion is performed.
Outstanding invoice amount.
Simple annual interest rate.
Number of days payment is overdue.

Calculation Results

Based on the figures you entered.

Primary Result$1,006.58
Late Interest$6.58
Days Late30 days
About this calculationThis uses simple interest on a 365-day year. Contract terms and local law may differ.

How the Late Payment Calculator Works

Calculate simple late-payment interest and the total amount due after a payment delay.

Late interest = invoice × annual rate × days late ÷ 365; total due = invoice + late interest.

Use the result as a planning estimate. Contracts, tax rules, platform terms and actual business costs may differ.

How to use this calculator

What to enter

Enter or select the following as requested: Currency — Display Only; Invoice Amount; Annual Late Interest Rate (%); Days Late. Follow the units, valid ranges, examples, and options displayed beside each field.

What the result means

The result estimates simple late-payment interest and the amount due using the invoice amount, annual rate and days late entered. Contract terms and local law may specify different rules.

When to use it

Use this for an estimate only; confirm the agreed terms and applicable legal requirements before charging interest.