In the past decade there has been an increasing scholarly interest in emotions in M&As. However, this research has put great emphasis on acquired employees’ negative emotions. This research contributes by analysing emotions in the acquiring organisation during a cross-border M&A. This research uses an analytical framework which is based on the cognitive appraisal and affective events theory. The research methodology is based on a single case study focusing on a Finnish-German acquisition. The findings suggest that emotions can be more negative in the acquiring firm than in the acquired unit in the beginning of the post-M&A integration, and that the acquirer and the acquired company can have an opposite emotional climate during the post-M&A integration phase. This might explain cultural clashes and acculturation stress in cross-border but also domestic M&A.