Initial sale success in the market with a new product is a critical milestone for a new venture. Failure at the introduction stage of a new product could have lethal consequences for the venture. In the present study, the authors investigate the role of a new venture company's first successful sale in the venture's future commercial success. The authors develop and test a model of the impact of the founders' entrepreneurial and commercial capabilities and proactive sales orientation on the significance of the first sale and sales growth of a new venture. Using survey data and partial least squares estimation, the results reveal that the founders' commercial capabilities have a positive effect on proactive sales orientation, while their entrepreneurial capabilities positively moderate the effect of commercial capabilities. Further, the results reveal that a proactive sales orientation positively affects the significance of the first sale and that value‐based selling approach positively moderates the effect of proactive sales orientation. Finally, the results reveal that the significance of the first sale is positively related to sales growth. Thus, the authors conclude that combining the founders' commercial and entrepreneurial capabilities strengthens proactive sales orientation and that, in turn, a proactive sales orientation particularly increases the significance of the first sale when new venture companies practice value‐based selling. Research has convincingly demonstrated proactive selling behavior to be one of the most powerful predictors of sales performance. Value‐based selling is a sales approach to identify, quantify, communicate, and verify value of a new product to the customer. Our findings suggest that founders who possess both strong commercial and entrepreneurial capabilities engage considerably more in proactive sales practice as compared with founders that only possess strong commercial capabilities. Hence, rather than hiring specific sales expertise, founders should develop their proactive, value‐selling capabilities.