Bidding zones are geographical areas in which market participants are able to exchange electricity without capacity allocation. They generally correspond to the borders of the EU Member States. A notable exception is the single bidding zone in Germany and Austria which is considered as a key element of electricity market integration in the EU. However, the increasing inflow of electricity into the German transmission system causes problems for certain neighbouring countries. This situation may trigger certain counter-measures and even lead to the reconfiguration of bidding zones in the interest of an overall improvement of the electricity flow. However, the split of a bidding zone into smaller sections might have discriminatory or other anti-competitive effects. The European Commission has therefore adopted sector-specific rules for such situations. The new EU regulation establishing a guideline on capacity allocation and congestion management sets, among others, the legal framework for bidding zone reconfigurations. Despite these specific rules, the reconfiguration of bidding zones can also fall under the EU competition rules, which will be the key focus of this article.