Phil has been practicing law for over 57 years. A native Washingtonian, Phil graduated from Coolidge High School and went on to attend Dartmouth for his undergraduate studies and graduated with an LLB from Yale Law School. Phil was a senior partner for almost forty years at Margolius Mallios & Rider. In 2002, he started a smaller version of his firm, where he could dedicate his time and take the utmost care in providing his services to his clients in a more personal setting.

Phil has been recognized as one of the District's best and top Real Estate lawyers and also as a preeminent Estate and Trust Lawyer. Phil has been a trusted legal, investment, trust and foundation advisor for local families. In 2009, Phil co-founded the BurnBrae Companies, which is a real estate firm, which specializes in development of homebuilding lots and owns and operates multifamily residences in Maryland, Washington, DC and South Carolina.

Phil was married to his wife Phyllis for 45 years. Phyllis passed away February 2014 after a courageous battle with cancer. They had three children, David, Kenny and Jennifer. Jennifer passed away in 2020. He is fortunate to be grandfather to Ma'ayan, Ro'i, No'a, Jocelyn and Jesse.

Phil is well known for his philanthropy. He has served as president of numerous Washington D.C. Jewish charitable organizations including the Jewish Federation of Greater Washington, the United Jewish Endowment Fund (currently the Community Foundation) and the Jewish Community Center of Greater Washington. He established the Phyllis Margolius Family Foundation in 2014 and currently serves as its president. He also established and is president of the Endowment Fund of Save A Child's Heart, an Israeli based organization that provides heart surgeries and care for children from third world countries as well as surgical training for doctors in those countries.

In 2022 he established the Phyllis G. Margolius Impossible Dream Award, which annually provides a cash award to an outstanding individual working as a professional for a Jewish organization in the Washington, DC area.

He is currently working on a project to permit Jewish organizations in the Washington, DC area to attract and retain the best and brightest talent to work in their organizations.