The UK left the EU on 31 January 2020. A transition period is currently in force, in principle until 1 January 2021. During this period most EU law, including its competition law, continues to apply in the UK. As we approach the potential midpoint of the transition period, it is useful to consider what will change at the end of the transition in terms of competition law enforcement and how to plan for the end of the transition period. At the end of the transition period, the UK's CMA will be empowered to review more mergers and conduct than before and is expected to be a key agency to consider when assessing risk and planning large global deals.