Belgium has published Circular 2021/C/87 of 5 October 2021, which provides guidance on the application of the 30% of EBITDA interest deduction limitation introduced from 1 January 2019 in compliance with the EU Anti-Tax Avoidance Directive (ATAD). One of the key aspects of the guidance concerns the grandfathering rules in respect of "old" loans entered into before 17 June 2016, which provide that interest on such loans are not subject to the new interest deduction limitation as long as no fu…