Ensuring equality for LGBTI+ individuals is a human rights imperative, but it also makes a lot of economic sense. Inclusion enables LGBTI+ individuals to achieve their full employment and labour productivity potential, benefitting not only their economic and social well-being, but also society as a whole. Yet, robust evidence supporting the economic case for greater LGBTI+ equality is still scarce due to challenges in accurately measuring the size and life situation of the LGBTI+ population. This report bridges this gap by using a unique set of microdata from the United States. The report begins with an overview of the share of US adults identifying as LGBTI+, their geographic distribution and key demographics. It then evaluates the extent to which LGBTI+ Americans face discrimination, assessing how this population fares, including in the labour market. Finally, utilising the OECD long-term model, the report quantifies the potential increase in GDP resulting from closing the unexplained LGBTI+ gaps in employment and labour productivity. The findings highlight significant economic gains, although they capture only a portion of the potential benefits. Notably, the broader societal impacts, such as the advancement of women's empowerment through the disruption of heteronormative standards, are not quantified.