Learning is a complex process that can be differentiated into assimilation and accommodation. The Internet enables both types of learning through collaboration. There is, however, little research investigating the specific impact of social and information incongruity on assimilation and accommodation. The current research investigates how the information incongruity between prior knowledge and new information on the one hand and the social incongruity caused by the group membership of an information source on the other hand stimulates assimilation and accommodation specifically. It is predicted that medium incongruity stimulates assimilation and accommodation more strongly than low incongruity. Moreover, concerning social incongruity, ingroup information should specifically increase assimilation more strongly than outgroup information. A laboratory study with a 2 × 2 design using between-subject factors "information incongruity" (low vs. medium) and "social incongruity" (ingroup vs. outgroup information) was conducted wherein participants worked on an ostensibly collaborative wiki. It was found that medium information incongruity stimulated stronger structuring of knowledge (i.e., internal accommodation) and stronger integration of new information into a wiki text (i.e., external accommodation) than low incongruity. As expected, ingroup information increased the acquisition of factual knowledge (i.e., assimilation) more strongly than outgroup information.