The home appliance industry, which includes electrical or mechanical devices used in a household, is a multi-billion-dollar industry. The state of Nuevo León is the main producer of household appliances in México and is also accountable for a large contribution of the national exports of this sector. For this reason, a Home Appliance Cluster exists, which is devoted to increasing this region’s competitiveness. By using a systematic literature review, a knowledge gap was discovered, regarding the factors of a cluster that determine the productivity of companies in this industry. Literature shows few to almost non-existing measurement instruments to analyze the impact that active participation within a cluster has on firm’s productivity. The present research finds three factors that come from belonging to a cluster and have an impact on firms’ productivity: geographic proximity, social capital and innovation. These factors, in the form of constructs, were put together to create a measurement instrument that will allow us to quantify the impact on firms’ productivity. The instrument was validated in three steps: First, through concordance and relevance tests. Second, there was a tuning meeting with clusters’ heads; and afterwards, construct validation took place when all data was gathered, with the use of Cronbach’s alpha. This study presents an analysis of each one of these factors, and how an instrument was created to measure the impact of a cluster on its members’ productivity.