Over the last few years, attention to the role of statewide political parties in multilevel polities has increased in recognition of their linkage function between levels of government, as these parties compete in both statewide and regional elections across their country. This article presents a coding scheme designed to describe the relationship between central and regional levels of statewide parties. It evaluates the involvement of the regional branches in central decision making and their degree of autonomy in the management of regional party affairs. This coding scheme is applied to statewide parties in Spain (the socialist PSOE and the conservative Partido Popular) and in the UK (Labour, the Conservatives and the Liberal Democrats). This coding scheme represents an additional tool to analyze party organization and facilitates the comparison of parties across regions and in different countries.