She had asked her partner not to send flowers, but a bouquet arrived anyway.

It was from her colleagues. And the last thing Billie Lynn Ross wanted to do was walk down to the lobby to claim them.

She had hoped to lie low that morning, to draw as little attention to herself as possible. But as she strode toward the reception desk of the Palo Alto building where she works, she realized that wasn’t going to happen.

“Holy hell,” the receptionist gasped. “Where did all this come from?”

Ross smiled. On that day in October 2014, she had shed her usual oversize superhero-patterned shirts and chunky skater shoes for a black dress and Oxford heels with red ribbons tied where the laces should go. Her hair was down, makeup done, nails freshly manicured.

She looked — at last — like herself.

After 24 months of preparation, hormone therapy and doctors’ visits, Ross became the only out transgender woman in her division of SAP, a large international software firm based in Germany. And rather than shirking attention, she has come to embrace it, speaking out for transgender visibility and inclusion at SAP and beyond.

Starting next year, the corporation’s 20,000 North American workers — roughly a quarter of its worldwide workforce — will be eligible, with their families, for what experts said are among the most progressive transgender benefits in the nation, including facial reconstructive surgery, total coverage of travel and lodging for out-of-town medical procedures, and puberty-suppression treatment for transgender children.

These policies — exceedingly rare among big and small companies alike — came after Ross, discovering how little of her own transition was covered by her health insurance, pushed for a more inclusive company policy.

“She was the change agent,” said Jewell Parkinson, head of human resources for SAP North America. “Absent that intervention and feedback, we may not have had the insight to make the changes that we did. She planted the seeds for us, she educated us and shared her experiences in such a way that allowed us to do the additional work to enhance our program.”

Transgender people, those who identify as a gender other than the one they were assigned at birth, may elect to undergo numerous procedures to affirm their gender identity.

SAP employees and family members covered by the company health plan were already eligible for what human resources experts regard as basic transgender benefits — hormone replacement therapy, mental health services and gender reassignment procedures. Those are among the most common transgender-specific benefits offered at other big-name tech firms such as Facebook, Netflix and Tesla.

Almost a third of big companies, those with 20,000 employees or more, cover gender reassignment surgery, according to a survey published this year by human resources consulting firm Mercer. But that number dwindles as companies get smaller, with about 10 percent of businesses with 500 to 5,000 employees offering the same.

The procedures SAP now offers, including facial feminization surgery, like the kind Ross had to soften her features, are much more rare.

About 2 percent of companies nationwide cover cosmetic procedures meant to feminize or masculinize a person’s facial appearance, according to a survey conducted by the Society for Human Resources Management.

Gender-reassignment benefits generally include multiple procedures: genital reconstructive surgeries as well as, in some cases, “top surgery,” or breast reduction or augmentation.

But other procedures that help transgender people pass, or be regarded by others as someone who was born biologically male or female, are often left out of coverage, said Diego Ramirez, a global health management consultant for Mercer. That’s because they are not deemed a medical necessity by insurance providers — though they can significantly impact the safety and well-being of transgender people.

These elective procedures can include hair removal, facial surgery, like chin or cheek implants, brow-bone reduction, collagen injections, Adam’s apple shaving and vocal pitch-altering surgeries.

“When you say you’re transitioning, everyone’s mind immediately goes to (gender reassignment) surgery,” said Ross, a product operations engineer at SAP Ariba. “But that really only affects my life, and my life with my partner. It doesn’t make a difference to me at work. But facial feminization surgery? Vocal surgery? Those do. If I have to hold a teleconference with 18 people in another country, and all they have to go on is my voice, they might not get that I’m female.”

In recent years, as transgender visibility has grown, companies have added benefits to aid transgender workers and their families. Most large health insurance providers, such as Kaiser and Aetna, which insure SAP workers, have policies that include gender reassignment surgeries. But the policies vary and depend on what the employer decides to make available to its workers.

About 1 in every 10,000 people suffers from gender dysphoria, a condition in people feel their emotional and psychological gender identity do not match the biological sex, according to the National Institutes of Health. So even at a large company such as SAP, the new benefits package may directly impact only a handful of people.

“We want to create an environment that allows them to be their authentic selves,” Parkinson said. “So does it really matter if it’s a small or large percentage of our workforce?”

Ross, 44, said her decision to come out at work was made easier by the fact that SAP had already offered transgender-inclusive health care and seemed welcoming to trans employees. Even so, it took two years for her to feel comfortable enough to come to work in heels.

She began her transition at the age of 40, though she had known there was “something different” about her since the age of 4. It took her years to articulate what that something was and still longer to begin her journey from Bill to Billie.

For two years after she began hormone replacement therapy, Ross hid under baggy men’s clothes and kept her long hair tied back.

“At work, I was scared to transition at first,” she said. “I just didn’t know what to expect.”

She certainly didn’t expect to inspire SAP to change its policies, but it did, announcing the new benefits through an all-staff email in October — almost exactly two years after Ross came out at work, and four years after she began her transition.

“It was great to see that my conversation had paid off,” she said.

But her work is not yet done. She’s planning another sit-down with HR to discuss name changes and the legal obstacles transgender people face in getting all their paperwork to match.

“Somewhere along the way, I realized you have to help educate people, and the best way to do that is through your own story,” she said. “The more people understand about trans people, the less afraid and in the dark they are. It helps all of us.”

Marissa Lang is a San Francisco Chronicle staff writer. Email: mlang@sfchronicle.com Twitter: @Marissa_Jae