Member states strategically make use of the phase of transposition of directives as a means to preserve their national competences, such as anti-money laundering and countering the financing of terrorism (AML/CFT) policy, vis-à-vis the European Union (EU), by choosing whether to water-down or enhance EU requirements. Both the motivations and dynamics of these ‘customisation’ choices have received limited attention in research, especially in relation to AML/CFT policy. I try to develop a theoretical framework which explores how the combination of “necessary” and “mediating” conditions, at European, domestic, and actors’ levels, can lead member states to tailor EU AML/CFT policy to their preferences. Making use of fuzzy-set Qualitative Comparative Analysis, I investigate the customisation of five rules outlined in the 5th AML directive (AMLD5) across the six founding member states (BE, FR, DE, LUX, NL, IT) in the period 2018-2020 (sample size N = 30). My analysis reveals that the strict categories of “necessary” and “mediating” factors partly fail in explaining customisation outcomes. While the goodness of fit conditions have a blurry impact on implementation strategies, both the tax/financial transparency cultures and the political preferences of countries have important implications for customisation outcomes. When member states have restrictive tax planning traditions and are politically favourable towards a measure, they tend to act as proactive problem-solvers and hence do not water-down EU rules. Moving along the policy cycle I then turn to new EU AML package to assess whether EU policymakers “have learnt” from previous implementation outcomes in the proposal of new legislation. My conclusions are clear: the European Commission has well identified the cases of fragmented transposition, and largely addresses them in its new legislative proposals. This research strives to build a more complete understanding of both the nuanced dynamics of customisation and the practice of policy evaluation by the Commission. By investigating this, I try to contribute to a deeper understanding of how member states assert their preferences in reaction to EU regulatory pressure, and in turn, how the Commission takes these preferences into account for future policymaking.