Invoice Late Fee Tool

Estimate a simple daily late fee from an invoice amount, monthly rate and overdue days.

Your inputsBuild a realistic scenario

Invoice amount

Monthly late-fee rate

Days overdue

days

Scenario referenceOperations decision model

Estimated fee = Invoice × Monthly rate × Days overdue ÷ 30

Start with a conservative case, then test the upside separately.

Live estimateYour scenario

● Updates instantly

Estimated late fee$24.00

Invoice plus fee$2,424.00

Decision tip

Record the assumption behind the result before comparing another option.

✓ Free to use✓ No account or saved data✓ Formula shown below

A quick workflow

Run a better scenario before you decide

Enter your current figures or scenario assumptions. Results update instantly, so you can compare a few realistic options and identify the input that actually changes the conclusion.

Set a baseline

Use a known current figure.

Change one driver

Keep the comparison clear.

Choose the next step

Use the evidence, not a guess.

Transparent calculation

The calculation used in this tool

CORE FORMULAEstimated fee = Invoice × Monthly rate × Days overdue ÷ 30

Only apply a fee if your contract and local law permit it. Check rate caps, notice requirements and grace periods.

Practical use

Turn the scenario into a more confident plan

Compare practical options

Use the same baseline across two scenarios so the difference is easy to explain.

Set a decision threshold

Decide in advance what result would change the next action, budget or priority.

Document assumptions

Save the source figures and time period so you can revisit the scenario later.

Use with care

What this planning estimate does not include

This tool makes its assumptions visible, but it cannot replace the terms, local rules, tax treatment or operational data that apply to your situation. Confirm material decisions with the relevant source records or adviser.

Values are calculated in your browser. No account or data upload is required for this tool.

Continue the analysis

Check the numbers behind this decision

Pair this scenario with a related calculator or planning tool before you commit.

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