The fashion industry is the third largest manufacturing industry in the world. Companies’ sustainability reports contain the organization's social, economic and environmental work. Comparability is a necessary principle for stakeholders to make investment decisions between companies based on their sustainability reports. Voluntary sustainability reporting has recently become more common. Furthermore, states årsredovisningslagen (ÅRL) in Sweden that certain companies are obliged to prepare sustainability reports. In the US, on the other hand, there are no requirements for companies to report about sustainability. The comparability between companies' sustainability reports is improved by following Global Reporting Initiative (GRI) standards. The purpose of the study is to make a comparison between Swedish and American companies' sustainability reports and within each country in the fashion industry. The aim is to see how well companies’ sustainability reports in the US and Sweden follow the principle of comparability in terms of indicators in GRI's standards. To investigate this, a quantitative and qualitative method have been used. Theories used in the investigation to study comparability in American and Swedish clothing companies are the institutional theory and the legitimacy theory. The study shows that comparability is generally deficient between the US and Sweden and within each country. Worst comparability was found between Sweden and the US but within each country, Sweden had the best comparability