Following the amendment of company listing agreements in 2012, which required the 100 top listed companies to submit their sustainability reports, this study suggests to compare the quality of these reports before (2011) and after (2021) using the sustainability reporting (SR) elements based on global reporting initiatives (GRI). For both years, we employed content analysis of 51 environmentally sensitive firms’ annual, integrated, and sustainability reports. The findings show a substantial upsurge in sustainability reporting quality (SRQ) from 2011 to 2021. The quality of SR improvement suggests that businesses are dedicated to reducing, if not eradicating, environmental deterioration and social well-being.