When Hint CEO Kara Goldin was weighing whether to add her name to a small but growing list of CEOs speaking out against restrictive abortion laws recently passed in Alabama, Georgia and other states, the answer was simple.

“It was really less about what my opinion is on abortion but more about the fact that I have employees all over the U.S.,” said Goldin, whose company’s fruit-infused bottled water is sold across the country and is popular at tech cafeterias around Silicon Valley. “We’re now up to 200 employees. We’re San Francisco-based but all over the U.S. When I look at health care, I think everyone should have the same rights.”

So Goldin joined 180 other CEOs in signing an open letter, which ran as a full-page ad in the New York Times last month, calling the abortion laws “bad for business” and saying, “Restricting access to comprehensive reproductive care, including abortion, threatens the health, independence and economic stability of our employees and customers.” The list of supporters has since grown to more than 300.

“It’s not about politics. It’s not about religion,” said Goldin, whose company is 65% female and has employees in some of the states that recently restricted abortion access. “It’s about every one of my employees being able to have equality no matter where they live. I think if you were to frame that for a CEO, ‘Well, do you believe in equality?’ They’d say, ‘Of course.’”

More than a dozen other Silicon Valley firms — including Yelp, Square, Slack, Reddit, Postmates and Zendesk — also backed the letter, one of the only public pronouncements of where corporate America stands on the divisive issue of abortion.

Absent from the conversation thus far, observers noted, are some of the tech executives who’ve led corporate activism on other social issues — like Salesforce CEO Marc Benioff, a vocal advocate for increasing funding for homelessness programs in San Francisco and a leading national voice a few years ago when he spoke out against so-called bathroom bills in North Carolina and other states that would have discriminated against transgender people. Salesforce did not respond to questions about whether it is taking action on the abortion policies.

“This is a highly charged issue, and right now our political climate is already so polarized that leaders may be really measured in their response to this one,” said Ann Skeet, senior director of leadership ethics at the Markkula Center for Applied Ethics at Santa Clara University. “They want to be careful. (Abortion) has been one of the toughest issues for our country.”

Unlike public opinion on LGBTQ rights and gay marriage, which has shifted dramatically over the last two decades in favor of supporting equal rights, opinion on abortion hasn’t changed much — perhaps leading many corporate leaders to be leery about taking too strong a stance, Skeet said. In the latest Pew Research survey of Americans, 58% of respondents said abortion should be legal in most cases, and 37% said it should be illegal in most cases.

Amid the vacuum, many smaller companies and those headed by female CEOs are emerging as leaders in the fight for abortion access. Some are experimenting with ways to offer their customers a path to funnel financial support to groups that advocate for women’s health and reproductive rights.

In the weeks after Alabama and Georgia passed legislation all but banning most abortions, Pandia Health, a Sunnyvale birth control delivery startup, introduced sign-up codes for new customers in which the company would donate $5 per order to Yellowhammer Fund, NARAL Pro-Choice America or Planned Parenthood.

“It makes me so angry and sad what’s going across the nation,” said Pandia CEO Dr. Sophia Yen. “I’ve just been lividly tweeting and Facebook-ing personally, not necessarily on behalf of the company, but as CEO and founder of this company. I know all our members value women’s rights, the right to birth control and access.”

The San Francisco delivery company Postmates is developing an in-app tool where customers can make a point-of-sale charitable donation to women’s health organizations by rounding up the balance on their delivery to the nearest dollar.

“Over 60% of our customers are women,” said Vikrum Ayer, Postmates’ vice president of public policy. “And we sell from over 500,000 local merchants annually, many of which are women-owned businesses. ... We thought it important to add our voice. For the women who sell, earn and purchase on our platform, your personal sovereignty needs to be prioritized over politics.”

Some corporate responsibility experts note that many major companies have not taken action on the matter. Other than Netflix and Hollywood studios that shoot movies and shows in Atlanta, few companies, if any, have publicly threatened to redirect investments or rethink expansion plans in Georgia, Indiana and other states that recently approved stricter abortion limits.

More visible public companies may be nervous about alienating customers, employees or investors, said Kellie McElhaney, who leads the Center for Equity, Gender and Leadership at UC Berkeley’s Haas School of Business.

Still, “it’s a lost opportunity for sectors like tech who already have a gender problem,” McElhaney said.

Susan McPherson, a communications consultant and corporate social responsibility expert who helped start the CEO open letter, had been working with NARAL Pro-Choice America, Planned Parenthood and the ACLU for months prior to the passage of the abortion bans, reaching out to companies to learn what it would take for them to make women’s access to contraception and choice a greater priority.

“Even the most conservative companies have come out regarding stands on climate and LGBTQ,” she said. “Our belief was those discussions started happening 10 to 15 years ago. We felt we needed to start this now, and it might take awhile.”

Catherine Ho is a San Francisco Chronicle staff writer. Email: cho@sfchronicle.com Twitter: @Cat_Ho