Chelsea Clinton was once doggedly averse to the attention of the news media, but she has taken on a larger public role in recent years. In April, when she said that she was expecting her first child with her husband, Marc Mezvinsky, she announced the news while onstage with her mother.

Ms. Clinton and her parents have devoted much of the past year to build up the family foundation’s endowment, and speaking engagements have been a part of that.

In August, they will most likely host another fund-raiser in the Hamptons, where they will spend their vacation. Mr. Bazbaz said Ms. Clinton was not paid for her role as the organization’s vice chairwoman. She does get a salary at NBC News (of $600,000 a year, before she recently switched to a month-to-month contract, according to Politico) where she became a special correspondent in 2011.

Ms. Clinton’s speeches focus on causes like eradicating waterborne diseases. (“I’m obsessed with diarrhea” is a favorite line.) And she dispenses lessons picked up from her family. (“Life’s not about what happens to you, it’s about what you do with what happens to you,” she likes to say.)

The speaking engagements often include question-and-answer sessions in which she fields inquiries about growing up in the White House and her mother’s plans for 2016. Ms. Clinton often says that she is “unapologetically biased” when it comes to her mother, and that “my crystal ball is no clearer than yours” on whether she will run for president again.

The cost to book Ms. Clinton surpasses that of speakers with longer résumés, like Jeb Bush, the former Florida governor and a potential Republican rival to Mrs. Clinton in 2016. He makes an estimated $50,000 per speech. Colin L. Powell and Madeleine K. Albright, both former secretaries of state, are also in the $50,000 range, said one person who has booked speakers but who could not discuss private contracts for attribution.

The Jewish Federation of Palm Beach County hired Ms. Clinton to speak at its inaugural event in March. Tickets started at $1,000 per family, and the event raised more than $2.1 million. “There is great synergy between federation’s work and Chelsea Clinton’s message,” said David Phillips, the group’s president and chief executive.