Purpose The purpose of this study is to investigate whether abnormal return patterns can occur on different share indices, as a result of the outcome in national team matches. The subordinary aim is to investigate whether there are differences between the three share indices, (small-, mid- and large cap) depending on the match category and how it relates regarding the five countries in the study. Method This study has a positivistic and deductive approach, using a modified event study methodology. The event period is one day after the event. For each nation, year and share index, different estimation periods have been created. The study comprises 760 national team football matches and is investigating how each different share index is affected by match outcomes in championship matches, qualifying matches and friendlies. Results Upon compilation of all 760 matches, the result of this study shows a statistically significant impact on two of the three possible match outcomes, regarding small cap index. Furthermore the result also shows a connection between friendly matches and small cap index. The match categories championship matches and qualifying matches demonstrates no connection to the three diffrent kind of share indices. Regarding the different nations, Spain and their small- and large cap index shows the most significant connection between the match outcome and abnormal return. Conclusions The small cap share index is basically the only index that is affected by the all the matches that is involved in this study (after a victory or a loss). The magnitude of a match does not seem to have a greater influence on investor rationality. Over all, the match outcome draw does not lead to negative abnormal return. Of this studys five surveyed countries (England, France, Spain, Sweden and Germany), the english and german share indicies seems to be least likley to be affected by the outcome in national team football matches.