Lampert was born in 1962 to Dolores Lampert and Floyd M. Lampert. His mother was a housewife. His Father was a senior partner in the law firm of Lampert & Lampert in New York City. He has a younger sister Tracey. Lampert's grandmother was a passive investor and big fan of Louis Rukeyser's Wall Street Week television program. She instilled in him an interest in investing. His mother would later recall that young Eddie would sit with his grandmother reviewing and evaluating the performance of her stock picks in the daily newspaper.

In July 1984, Lampert worked as an intern at Goldman Sachs, and then worked in the firm's risk arbitrage department from March 1985 to February 1988. While there, he worked directly with Robert Rubin. When Lampert decided to go out on his own, Rubin warned him it would be a bad career decision.

In April 1988, Lampert left the bank to form ESL Investments, based in Greenwich, Connecticut (the name ESL derives from Lampert's initials). richard Rainwater, whom Lampert had met on Nantucket Island, gave him $28 million in seed money and introduced him to clients, such as David Geffen.

In 2001, he married Kinga Lampert and they have three children. They have homes in Indian Creek Village, Florida, Aspen, Colorado, and Greenwich, Connecticut. The couple are active members of their local Chabad house.

In 2003, Lampert was kidnapped from the parking lot of his Greenwich office, but was able to convince his captors to let him go after two days of captivity.

Lampert's earnings in 2004 were estimated to be $1.02 billion, making him the first Wall Street financial manager to exceed an income of $1 billion in a single year. In 2006, Lampert was featured on the Time 100 list for most influential people in the world for being one of the "brightest minds on Wall Street" and leading a new class of Activist hedge funds. Lampert was the richest person in Connecticut in 2006 with a net worth of $3.8 billion.

Lampert's earnings in 2006 were estimated to be from $1.0 to $1.5 billion.

In March 2012, Lampert was No. 367 on the Forbes world wealthiest people list with a net worth of $3.1 billion. By August, 2016, Lampert had fallen to No. 810 on the list, with a net worth of $2.2 billion.

In January 2013, it was announced that Lampert would take over as chief executive officer at Sears after Louis D'Ambrosio stepped down due to family health matters, which took effect in May 2013. In July 2016 he held 28% of shares in Sears Holdings Corp worth of approximately $408 million.

In early 2017, Lampert, then President, chief executive officer and top shareholder of Sears Holdings, was estimated to have personal assets of $2 billion, primarily in the hedge fund ESL Investments Inc. Early in the year, he committed to providing an additional loan of $500 million to Sears and said he would provide letters of credit to Sears for additional amounts, reportedly totaling $200 million and possibly increasing to a half billion dollars in the Future.