Bill Daniels, the longtime owner and president of Marin’s United Markets grocery stores, died Thursday at his home in Novato. He was 75.

“He will be sorely missed as a friend, a counselor, an adviser, an owner, a father and grandfather,” Mr. Daniels’ son, Mark Daniels, said Monday. “However, he has left a lasting mark on the landscape of Marin.”

He said the cause of death was heart failure associated with a short-term illness.

Mr. Daniels was remembered not only for his own business but also for his support of local businesses and his philanthropy in the community.

“We want people to feel good about United and the community,” Mr. Daniels said in 2014, when the San Rafael store celebrated completion of a remodeling project. “We’re just trying to bring everyone together.”

Mr. Daniels was born in Placerville in 1943 and moved with his family in the mid-1950s to Mill Valley, where he attended Tamalpais High School. He entered the grocery business at age 17 at Purity Markets in Marin. After graduating from Tam, he served for four years in the U.S. Air Force. When he returned to Marin he was hired as a clerk in 1965 at United Markets in San Anselmo.

Joe Saccone, who along with his late brother, Ben, founded the first United Markets store in San Rafael in 1955 and the San Anselmo store in 1959, hired Mr. Daniels, who eventually became the San Anselmo store manager.

In 1982, the Saccones sold the two United Markets stores to Mr. Daniels and longtime employee Bob Musante, who ran them as partners until 2007, when Musante retired.

While Musante said he liked to operate in the background, he remembers Mr. Daniels as the “face of United Markets” and a hard worker.

“He was driven and he took pride in the market,” Musante said. “It was almost like a stepchild to him. He put every ounce of energy he had in seeing to it that the business flowed in the direction that he wanted it to go.”

Mr. Daniels took full ownership of the markets in 2013 and ran them with his daughter, Kelly Smith, for several years.

Ed Gilardi, who has worked for United Markets for nearly 40 years — currently serving as the director and buyer for the produce department in San Anselmo — said Mr. Daniels would often work 12- to 14-hour days, seven days a week. He loved every facet of the business, Gilardi said.

Mr. Daniels also considered employees to be like family and always took time to talk to customers if they had questions or concerns, Gilardi and others said.

“His heart was so much in that business,” Gilardi said. “It’s going to be hard to imagine United Markets without him.”

Mr. Daniels was also known for helping foster several small, local businesses.

“Mr. Daniels made it his business to help other local entrepreneurs get started by featuring them in his grocery stores and offering them prime shelf space, when this was nearly impossible,” said Beau Blanchard, chairman of the San Rafael Chamber of Commerce board of directors. “His generosity and neighborhood spirit will be missed.”

Gilardi said Mr. Daniels believed that small businesses were essential to retaining the community’s character. He was proud to be running stores with union employees. He strongly opposed larger corporate stores like Target from moving in.

“He took great pride in being ‘Home Grown in Marin,'” Mark Daniels said. “His family members would often ask if he would consider expanding United Markets outside of Marin, but he always said that he wanted to be physically close to the stores. He liked to inspect the meat and produce daily, rotating and positioning the fruits. He was literally ‘hands on.'”

In other ways, Mr. Daniels was ahead of his time, Gilardi said. United Markets became one of the first Marin grocery stores to halt cigarette sales in 2002.

Aside from the store, Mr. Daniels’ love was his wife, Sandy. The two were high school sweethearts at Tamalpais High and were married in 1965. The two remained at each other’s side until her death in 2013 after a five-year battle with breast cancer. In the following years Mr. Daniels held fundraisers, such as the annual Sandy Daniels Bocce Ball Tournament, to raise money for breast cancer research.

Mr. Daniels also raised funds for veterans, the Marin Agricultural Land Trust and the San Rafael Pacifics baseball team, said colleagues and family. A community cards program at the market provided 3 percent of proceeds to 70 local schools.

In addition to his son and daughter, Mr. Daniels is survived by a brother, Richard Daniels of Sacramento, and five grandchildren.

“His biggest smiles and loudest laughs came when spending time with his grandchildren, who always wanted to make ‘Papa’ laugh,” Mark Daniels said. “He always commented that they always made him proud.”

The family has not yet announced service arrangements.