Statutory Interest calculator

Welcome to the Daniels Silverman Statutory Interest Calculator. This will allow you to calculate how much interest you can charge a debtor for late payment under The Late Payment of Commercial Debts Act 1998. This right to charge interest is irrespective of what is contained in your normal Terms and Conditions. Click here for more information.


(tick for yes)
Number of employees (Creditor)  (numbers only)
Number of employees (Debtor)  (numbers only)
Total invoice value (inc VAT)  (numbers only)

This calculator is written in JavaScript. If for any reason your browser cannot support JavaScript or you are experiencing difficulty in making the calculator work, please look at the following instructions below with regard to manually calculating your interest calculations.

The formula used by the interest calculator is as follows:
Debt times the interest rate times the number of days late divided by 365

The daily rate is calculated as follows:
Debt times the interest rate divided by 365

If the base rate is 4% for the six-month period when the debt became late, then the statutory interest rate is 12% (4% base rate plus 8%)
Debt is £851.06 plus £148.94 VAT = total £1,000
If this debt is 30 days late, then the interest owed is:
£ 1,000 x 12% = £120 (the annual rate)
£ 120 ÷ 365 = 32.9p (the daily rate)
32.9 pence x 30 days = £9.86 (the interest owed to date)

The interest rate which applies to your debt is identified as follows:
For contracts dated prior to 7th August 2002 the late payment interest rate is 8% plus the Bank of England base rate that was in place on the day the debt became overdue. For information on the Bank of England base rates, please click here

For contracts dated on or after 7th August 2002 the late payment interest rate is 8% plus the reference rate. The current reference rate for the period 1st January 2008 to 30th June 2008 is 5.5%