Late Fee Calculator

Calculate accrued interest and late fees on overdue invoices. Enter your invoice amount, due date, and choose a rate type (flat fee, monthly percentage, or statutory). Results are shareable via URL.

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Results

Invoice Amount

$5,000.00

Days Late

0

Daily Accrual

$1.10

Accrued Interest

$0.00

Total Due Today

$5,000.00

Rate: 8% per annumsource

Understanding the rates

Flat Fee

A one-time fixed charge added for non-payment (e.g., $50 admin fee). Does not accrue daily.

Percentage (Monthly)

Monthly interest accrued daily. 2% per month ≈ 0.067% per day. Useful for payment plan scenarios.

Statutory (UK)

The Late Payment of Commercial Debts (Interest) Act 1998 establishes 8% per annum plus the Bank of England base rate. Applies automatically to commercial transactions unless a different rate is agreed in writing.

Statutory (EU)

Late Payment Directive 2011/7/EU sets minimum 8% annual interest plus reference rate. Member states may set higher rates. Always check your country's implementation.

Questions

What is a late fee vs. interest on overdue invoices?

A late fee is a fixed charge (e.g., $50) or percentage added for non-payment. Interest (or statutory interest) accrues daily and compounds based on how long the invoice remains unpaid. Many contracts include both.

Are late fees enforceable if not stated in my contract?

Not reliably. Always state late fees clearly in your payment terms before you invoice. Statutory interest (8% in the UK and EU, state-dependent in the US) may apply without a contract clause in commercial transactions.

What is the UK statutory interest rate?

The Late Payment of Commercial Debts (Interest) Act 1998 sets a base rate of 8% per annum plus the Bank of England base rate. This applies to commercial transactions in the UK unless the contract specifies otherwise.

Can I use a higher rate than the statutory minimum?

Yes, if your contract specifies it and it is permitted under local law. But rates above statutory minimums may be unenforceable or subject to reasonableness challenges, especially for consumer debt.

How do I calculate daily accrual?

Multiply the invoice amount by the daily rate (annual rate ÷ 365 ÷ 100), then by the number of days late. This gives an approximation; exact calculation depends on your jurisdiction and contract.

Should I add interest or late fees to a payment plan?

Only if your original contract allows it and local law permits. Include the term clearly in the payment plan agreement so the debtor understands the full obligation.

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