you can start charging interest www.gov.uk/late-commercial-payments-interest-debt-recovery www.gov.uk/late-commercial-payments-interest-debt-recovery long-overdue payments gov.uk Late Payments of Commercial Debts Act. current government legislation gov.uk hub Late Payment of Commercial Debts (Interest) Act 1998 Late Payment of Commercial Debts (Interest) Act 1998 charge interest on unpaid invoices Late payments information