In August 2016, the European Commission announced its largest-ever aid recovery order, requiring Apple to repay EUR 13 billion as a result of its tax arrangements in Ireland. This landmark tax State aid decision followed aid recovery orders faced by Starbucks in the Netherlands, Fiat Finance and Trade in Luxembourg, and 35 other multinationals in Belgium under the “excess profit” scheme. As it has been reported that a large number of tax rulings are under review, companies’ tax arrangements face an unprecedented level of State aid scrutiny. This article provides an overview of the State aid framework and procedure, reviews the status of the ongoing tax State aid investigations, highlights the key economic issues raised by the Commission in the Apple case, and discusses how an economic and financial analysis can help companies mitigate future State aid risks, in light of the importance of ensuring that tax arrangements are State aid-compliant.