The full scale of the destructive effect that the COVID-19 pandemic has brought on virtually all aspects of life is not yet fully clear. However, it is evident that the pandemic already had profound consequences for international affairs in general and security policy more specifically. These developments, in turn, have also affected a cornerstone of Euro-Atlantic security, the North Atlantic Treaty Organisation (NATO). Although infectious diseases are hardly a chief concern for the organisation, heads of the member states and senior decision-makers within NATO have underlined that the spread of COVID-19 at least bears indirect consequences for the alliance. In order to measure the effect of COVID-19 on NATO, the following analysis will first describe the status quo within NATO before the spread of the disease. Secondly, it will examine the direct effects the virus has had on NATO. Lastly, this analysis will look at the extent to which the virus has altered transformation processes in the political and security environments and thus has had an indirect effect on the alliance.