The LGBT Equality Index ranks companies by how well they respect the rights of employees and other members of the lesbian, gay, bisexual and transgender (LGBT) community.
It currently covers 201 US-based firms, but Credit Suisse said it hoped to expand the index and associated investment portfolio, unveiled Monday in New York, to other countries.
The portfolio is currently only available to US-based private banking clients able to spend a minimum of $250,000 but could be open to smaller investors next year.
Doug Nieters, co-head of the LGBT network of Credit Suisse employees in the United States, told AFP the idea emerged from discussions among the network's members.
"The next step of the discussion, which started about two and a half years ago, was to say, 'Wouldn't it be great to connect the bottom line to pro-LGBT policies?'" he said.
The team commissioned research on the correlation of company performance with their LGBT policies.
The results showed that "if companies do have pro-LGBT policies, they can retain people for longer, people tend to be happier in the job, they tend to be more engaged at work, all those things that lead to more production and a more positive, solid bottom line," said Nieters.
The Credit Suisse gauge uses criteria developed by the US-based Human Rights Campaign's Corporate Equality Index, which gives points for policies ranging from health benefits for LGBT partners to codes of conduct that respect sexual orientation.
To feature on the bank's list, companies must score at least 80 percent on the Corporate Equality Index.
"What we really want to do is show a positive correlation between pro-LGBT policies -- good hiring practices, good health benefits -- and the bottom line," said Nieters.
"Our hope with the index and the portfolio is that companies across America, but eventually also across the globe, will say, 'We see a clear a business case for us to change our model and adopt LGBT friendly policies,'."