The states of the Federal Republic of Germany implemented educational standards and mandatory testing for controlling and improving the quality of public schooling. The success of this reform highly depends on teachers’ acceptance and sensemaking of external feedback data. A theoretical model suggests that features of the testing system and institutional context factors on the system level and the school level moderate teachers’ interpretation and usage of school performance feedback. A preliminary cross-country teacher survey revealed differences in teacher acceptance of external testing feedback between two German states with different approaches to mandatory testing. This paper aimed at testing if the country difference remains stable when analyzing a larger sample size (n = 1,777) and controlling for more contextual factors on the school level (test subjects, tracking, teacher cooperation, discussion of performance feedback in faculty meetings). Multiple regression analyses and a multivariate analysis of variance and covariance approved the difference in teachers’ perspective on curricular validity, diagnostic usage and negative consequences of mandatory testing between the two German states. The paper eventually discusses to what extent the states’ testing system and other institutional context variables account for the differences in teachers’ view on performance feedback data.