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Late payment calculator

An invoice unpaid for 60 days is not "still outstanding" — it has cost you money twice: what you could have been earning with it, and what the delay is now charging. Put the invoice in and see the running total, plus the one-line figure you can put in a reminder.

Invoice amount ($)

Days overdue

Annual interest rate (%)

The rate written into your terms. If you didn't write one in, use your cost of money (an overdraft or card rate is a fair stand-in).

Late fee per month (%)

Commonly 1–1.5% a month. Charged proportionally by days, not per part-month.

One-off admin fee ($)

What you earn a week elsewhere (%)

Optional. What the money would have returned had it been working while you waited. 0 to ignore.

Nothing is sent anywhere. Every figure recalculates as you type and nothing is stored.

Check the maths

What is being charged, and on what basis

daily interest     = amount × (annual rate ÷ 100) ÷ 365
interest to date    = daily interest × days overdue
late fee to date    = amount × (monthly rate ÷ 100) × (days ÷ 30)
total owed          = amount + interest + late fee + admin fee

The fee is prorated by days rather than charged in blocks, so a 10-day delay doesn't cost a whole month's fee.

Read this before you send it

These are arithmetic, not entitlementsWhether you may charge them depends on your contract and your country's law

Interest must be agreed firstPut the rate in your terms before the work starts

Caps existSome jurisdictions cap late fees and statutory rates differ widely

Not legal or financial adviceCheck the rules that apply to you before enforcing anything

Margin calculator Break-even calculator Invoice tool

The next step

Stop the delay happening at all

Clear terms and staged deposits are what stop an invoice going stale in the first place. Raise the next one with the free generator.

Open the invoice generator What is your total leak?