The Late Payment of Commercial Debts (Interest) Act 1998 shall come into force on 1st July 1999 in relation to contracts for the supply of goods or services made on or after that date between a small business supplier and any purchaser who is a United Kingdom public authority.

The question whether a contract falls within this description is to be determined by reference to the circumstances when the contract is made and, accordingly, is not affected by any subsequent change in those circumstances.