Although the use of social media can be regarded as an everyday practice in many museums by now, several studies suggest that museums take monologic communication approaches in their social media communication. This study analyses 22 Danish natural science museums’ use of social media during one month in 2013. The findings confirm that the use of social media on museums’ own websites is generic in nature, not integrated with content, and monologic in form. Conversely, many museums deliver just the opposite mode of communication on Facebook where they initiate a broad range of dialogic genres featuring intense publication activities and high rates of response. The article discusses how the identified trends on the one hand emphasise that many museums have embraced a deportalised communications approach, while the trends on the other hand still demonstrate a very narrow range of web services beyond Facebook.