America's richest self-made woman grew up on a dairy farm—now she has a net worth of $20.9 billion

Growing up on a dairy farm in Osseo, Wisconsin, Diane Hendricks always pictured her future self wearing suits, driving nice cars and working in a city.

Today, the 77-year-old has an estimated net worth of $20.9 billion — nearly double her reported net worth from just two years ago — topping Forbes' most recent list of America's Richest Self-Made Women for the seventh year in a row.

Her fortune is largely from her roofing supplies ABC Supply. Hendricks built the Beloit, Wisconsin-based company with her late husband in 1982, and is currently its chairwoman. She owns 100% of the company, the company's website says.

ABC Supply brought in $20.4 billion in revenue last year and has more than 900 branch locations, according to Forbes.

A farm-grown work ethic

At age 10, Hendricks looked out a window and thought, "I don't want to be a farmer, and I don't want to marry a farmer," she told Forbes last year. Instead, she pictured herself wearing a "blue suit and having a nice car and being independent," she said.

That epiphany, combined with watching her parents work on the farm, made Hendricks dream of a career of her own, she said. Then she got pregnant at age 17, and finished her senior year of high school while living at home.

Three years later, she filed for divorce from her high school sweetheart, and as a single mother, got by on a series of odd jobs — even working as a Playboy Bunny waitress — while building a real estate career, she said.

"That's when I really started to look at a career, a career I'd always dreamt of having, which was being in business," said Hendricks.

After she met and married roof contractor Ken Hendricks in the 1970s, the duo co-founded ABC Supply. The company hit $1 billion in annual sales for the first time in 1998, according to the company's website.

Controversies and contributions

The success hasn't come without controversy. In 2016, the first year Hendricks topped the America's Richest Self-Made Women list, the Milwaukee Journal Sentinel reported that she "didn't pay a dime in state income tax from 2012 through 2014." She also didn't owe any money in state taxes in 2010, according to the news outlet.

That's not necessarily illegal, ABC Supply tax director Scott Bianchini told CNBC Make It in 2022. The company had changed its tax classification from a C-corp to an S-corp during those years. Under Wisconsin state law, corporations can apply to be S-corps on a federal level and C-corps on a state level, meaning ABC Supply could elect out of state tax-option status — potentially including any checks made out from the company to Hendricks — if all of its federal taxes were paid off.

Hendricks is still based near Beloit, which has less than 37,000 residents. She's bought and transformed several of the town's historic buildings and older businesses, and spent millions of dollars on local projects to rebuild abandoned properties and bring in new businesses to the state, according to Forbes.

In 2017, Hendricks opened a local career center to host skill workshops for middle and high schoolers, on topics like coding and construction. The program aimed to expose teens to "the value of a job," she told Forbes at the time.

"Children are like, 'Wow, is that how a welder works?'" Hendricks said. "They can go to vocational school and become a welder that'll pay $50,000 a year. Those are good jobs. Really good jobs."

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