During the summer 2020, after a long period of lockdown, the Italian government needed to find a way to launch the economy affected by a negative GDP, as well as to fight climate change. The Superbonus is not a new tax incentive per se. In fact, starting from the early 2000’s the Italian tax system has introduced various “temporary” tax breaks for house renovations and energy efficiency improvements, starting from a 36% tax coefficient. Since the years have passed, this mechanism has been greatly promoted by governments on both sides of the political spectrum, sometimes increasing the deductibility percentage, sometimes expanding the qualifying works attracting such tax breaks. The government decree DL 34/2020 has increased the deductibility percentage to 90% for qualifying energy efficiency expenditure paid from July 1st 2020 up to December 31st 2021. The 2021 budget law (legge n. 178 del 30 dicembre 2020) has extended the deadlines, as well as modifying certain procedures to obtain the bonus. Generally speaking, the superbonus 90% applies to the following works: − Seismic improvements as per the art. 16-bis TUIR; − Energy efficiency improvements (ecobonus) as per the art. 14 DL 63/2013. Because the Superbonus 90% is more generous than the other tax breaks, the law requires a more complex procedure to benefit from such relief. In this book, we will explain to you the procedure to claim the Superbonus 90% step by step.