In August 2010, Bloomberg signed
The Giving Pledge, whereby the wealthy pledge to give away at least half of their wealth. In his lifetime, he has given away $24.5 billion overall, including $4.3 billion in 2025. Through the foundation, he donated or pledged $767 million in 2018, and more than $1 billion in 2019. In 2011, recipients included the
Campaign for Tobacco-Free Kids;
Centers for Disease Control and Prevention;
Johns Hopkins Bloomberg School of Public Health;
World Lung Foundation and the
World Health Organization. According to
The New York Times, Bloomberg was an "anonymous donor" to the
Carnegie Corporation from 2001 to 2010, with gifts ranging from $5 million to $20 million each year. The
Carnegie Corporation distributed these contributions to hundreds of New York City organizations ranging from the
Dance Theatre of Harlem to
Gilda's Club, a non-profit organization that provides support to people and families living with cancer. He continues to support the arts through his foundation. Bloomberg gave $254 million in 2009 to almost 1,400 nonprofit organizations, saying, "I am a big believer in giving it all away and have always said that the best financial planning ends with bouncing the check to the undertaker."
COVID-19 response During the 2020
COVID-19 pandemic and its aftermath, Bloomberg through his foundation committed to a wide range of urgent causes including researching treatments and vaccines, leading contact tracing to root out the virus, supporting the World Health Organization, and funding global efforts to fight the spread of the disease and protect vulnerable populations. Action included: • Cofounding a $75 million fund for nonprofits impacted by COVID-19 in New York City • Donating $6 million to
World Central Kitchen to serve meals to health care workers in New York City • Partnering with Johns Hopkins University to train COVID-19 contact tracers through its school of public health and search for a treatment of the virus. • Convening mayors through a partnership with Harvard College to learn and discuss their pandemic response, featuring a bipartisan roster of speakers and attendees. • Leading New York's contact tracing effort • Launching an information and action sharing network for cities through the
National League of Cities • Supporting international efforts to combat the spread of COVID-19 and prepare regional leaders through the
International Rescue Committee, the
World Health Organization, Vital Strategies and other partners
Environmental advocacy Bloomberg is an environmentalist and has advocated policy to fight climate change at least since he became the mayor of New York City. Between 2015 and 2025, Bloomberg pledged over $3 billion to environmental efforts and policies. In September 2023, the
New York Times called Bloomberg "perhaps the world's single largest funder of climate activism." At the national level, Bloomberg has consistently pushed for transitioning the United States' energy mix from fossil fuels to clean energy. In July 2011, Bloomberg Philanthropies donated $50 million to
Sierra Club's
Beyond Coal campaign, allowing the campaign to expand its efforts to shut down
coal-fired power plants from 15 states to 45 states. In 2015, Bloomberg announced an additional $30 million contribution to the Beyond Coal initiative, matched with another $30 million by other donors, to help secure the retirement of half of America's fleet of coal plants by 2017. In July 2017, Europe Beyond Coal was established to phase out use of coal on the continent by 2030. Austria closed its final coal-fired plant in April 2020. In early June 2019, Bloomberg pledged $500 million to reduce climate impacts and shut remaining coal-fired power plants by 2030 via the new Beyond Carbon initiative. In September 2023, Bloomberg committed another $500 million to Beyond Carbon to "finish the job on coal." Bloomberg Philanthropies awarded a $6 million grant to the
Environmental Defense Fund in support of strict regulations on
fracking in the 14 states with the heaviest natural gas production. In 2013, Bloomberg and Bloomberg Philanthropies launched the Risky Business initiative with former Treasury Secretary
Hank Paulson and hedge-fund billionaire
Tom Steyer. The joint effort worked to convince the business community of the need for more sustainable energy and development policies, by quantifying and publicizing the economic risks the United States faces from the
impact of climate change. In January 2015, Bloomberg led Bloomberg Philanthropies in a $48-million partnership with the Heising-Simons family to launch the Clean Energy Initiative. The initiative supports state-based solutions aimed at ensuring America has a clean, reliable, and affordable energy system. Since 2010, Bloomberg has taken an increasingly global role on environmental issues. From 2010 to 2013, he served as the chairman of the
C40 Cities Climate Leadership Group, a network of the world's biggest cities working together to reduce
carbon emissions. During his tenure, Bloomberg worked with President
Bill Clinton to merge C40 with the
Clinton Climate Initiative, with the goal of amplifying their efforts in the global fight against climate change worldwide. He serves as the president of the board of C40 Cities. In January 2014, Bloomberg began a five-year commitment totaling $53 million through Bloomberg Philanthropies to the Vibrant Oceans Initiative. The initiative partners Bloomberg Philanthropies with
Oceana,
Rare, and Encourage Capital to help reform fisheries and increase sustainable populations worldwide. In 2018, Bloomberg joined
Ray Dalio in announcing a commitment of $185 million towards protecting the oceans. In 2014,
United Nations Secretary General Ban Ki-moon appointed Bloomberg as his first Special Envoy for Cities and Climate Change to help the United Nations work with cities to prevent climate change. In September 2014, Bloomberg convened with Ban and global leaders at the UN Climate Summit to announce definite action to fight climate change in 2015. In 2018, Ban's successor
António Guterres appointed Bloomberg as UN envoy for climate action. He resigned in November 2019, in the run-up to his presidential campaign. On 5 February 2021, however, he was re-appointed by Guterres as his Special Envoy on Climate Ambition and Solutions in the lead-up to the climate conference in
Scotland scheduled for November 2021. In late 2014, Bloomberg, Ban Ki-moon, and global city networks
ICLEI-Local Governments for Sustainability (ICLEI),
C40 Cities Climate Leadership Group (C40) and
United Cities and Local Governments (UCLG), with support from UN-Habitat, launched the
Compact of Mayors, a global coalition of mayors and city officials pledging to reduce local greenhouse gas emissions, enhance
climate resilience, and track their progress transparently. To date, over 250 cities representing more than 300 million people worldwide and 4.1 percent of the total global population, have committed to the Compact of Mayors, which was merged with the
Covenant of Mayors in June 2016. In 2015, Bloomberg and
Paris mayor Anne Hidalgo created the Climate Summit for Local Leaders. which convened assembled hundreds of city leaders from around the world at
Paris City Hall to discuss fighting climate change. The Summit concluded with the presentation of the Paris Declaration, a pledge by leaders from assembled global cities to cut carbon emissions by 3.7 gigatons annually by 2030. During the
2015 UN Climate Change Conference in Paris,
Mark Carney,
Governor of the Bank of England and chair of the
Financial Stability Board, announced that Bloomberg would lead a new global task force designed to help industry and financial markets understand the growing
risks of climate change. Following President
Donald Trump's announcement that the
U.S. government would withdraw from the Paris climate accord, Bloomberg outlined a coalition of cities, states, universities and businesses that had come together to honor America's commitment under the agreement through 'America's Pledge'. Bloomberg offered up to $15 million to the
UNFCCC, the UN body that assists countries with climate change efforts. About a month later, Bloomberg and California Governor
Jerry Brown announced that the America's Pledge coalition would work to "quantify the actions taken by U.S. states, cities and business to drive down greenhouse gas emissions consistent with the goals of the Paris Agreement." In announcing the initiative, Bloomberg said "the American government may have pulled out of the Paris agreement, but American society remains committed to it." Two
think tanks,
World Resource Institute and the
Rocky Mountain Institute, will work with America's Pledge to analyze the work cities, states and businesses do to meet the U.S. commitment to the Paris agreement. In May 2019, Bloomberg announced a 2020 Midwestern Collegiate Climate Summit in
Washington University in St. Louis with the aim to bring together leaders from Midwestern universities, local government and the private sector to reduce climate impacts in the region. Expanding on the work of Beyond Coal and Beyond Carbon, Bloomberg launched Beyond Petrochemicals in September 2022. The campaign takes aim at the rapid expansion of U.S. petrochemicals and
plastic pollution. The $85 million campaign aims to block the construction of 120 proposed petrochemical projects in Louisiana, Texas and the
Ohio River Valley. The 2023 finalists were announced at the Earthshot Prize Innovation Summit in September 2023 in New York, and the five winners were announced in November 2023 in Singapore.
Johns Hopkins University philanthropy As of 2024, Bloomberg has given more than $4.55 billion to
Johns Hopkins University, his alma mater, making him "the most generous living donor to any education institution in the United States." His first contribution, in 1965, had been $5. Bloomberg's contributions to Johns Hopkins "fueled major improvements in the university's reputation and rankings, its competitiveness for faculty and students, and the appearance of its campus," Bloomberg also funded the launch of the
Bloomberg–Kimmel Institute for Cancer Immunotherapy within the Johns Hopkins School of Medicine in East Baltimore, with a $50 million gift; an additional $50 million was given by philanthropist
Sidney Kimmel, and $25 million by other donors. It will support cancer therapy research, technology and infrastructure development, and private sector partnerships. In 2016, Bloomberg joined
Vice President Joe Biden for the institute's formal launch, embracing Biden's "
Cancer Moonshot" initiative, which seeks to find a cure for cancer through national coordination of government and private sector resources. The donation also increased financial aid for students enrolled in nursing, public health and other graduate programs.
Other educational and research philanthropy In 1996, Bloomberg endowed the William Henry Bloomberg Professorship at
Harvard University with a $3 million gift in honor of his father, who died in 1963, saying: "Throughout his life, he recognized the importance of reaching out to the non-profit sector to help better the welfare of the entire community." In 2015, Bloomberg donated $100 million to
Cornell Tech, the applied sciences graduate school of
Cornell University on the school's Roosevelt Island campus. Through Bloomberg Philanthropies, Bloomberg established the American Talent Initiative in 2016 which is committed to increasing the number of lower-income high-achieving students attending elite colleges. Bloomberg Philanthropies also supports CollegePoint which has provided advising to lower- and moderate-income high school students since 2014. In 2016, the
Museum of Science, Boston, announced a $50 million gift from Bloomberg. Bloomberg credited the museum with sparking his intellectual curiosity as a patron and student during his youth in
Medford, Massachusetts. It is the largest donation in the museum's 186-year history. Bloomberg donated $100 million to America's four Historically Black Medical Schools in 2020 as part of Bloomberg Philanthropies' Greenwood Initiative, which tackles the racial wealth gap and addresses decades of under-investment in Black communities. The gift to
Meharry Medical College,
Howard University College of Medicine,
Morehouse School of Medicine and
Charles R. Drew University of Medicine and Science provided grants to reduce debt for students, meaning many medical students enrolled at the time and for the four years to follow would graduate free of debt. In April 2022, Bloomberg announced two separate $100 million donations, one to Harlem Children's Zone's Promise Academy and another to
Success Academy Charter Schools. In 2024, Bloomberg again made a donation to the nation's Historically Black Medical Schools — this time gifting $600 million to the four schools to support their endowments. The New York Times reported the endowments were "significantly underfunded" due to entrenched discrimination, but Bloomberg's gift was expected to increase three of the schools' endowment sizes by more than 100%. The donation also included $5 million to help
Xavier University to establish a new medical school.
Urban innovation philanthropy In July 2011, Bloomberg launched a $24 million initiative to fund "Innovation Delivery Teams" in five cities. The teams are one of Bloomberg Philanthropies' key goals: advancing government innovation. In December 2011, Bloomberg Philanthropies launched a partnership with online ticket search engine
SeatGeek to connect artists with new audiences. Called the Discover New York Arts Project, the project includes organizations HERE,
New York Theatre Workshop, and the
Kaufman Center. In 2013, Bloomberg announced the Mayors Challenge competition to drive innovation in American cities. The program was later expanded to competitions in Latin America and Europe. In 2016, Bloomberg gave Harvard $32 million to create the Bloomberg Harvard City Leadership Initiative within
Harvard Kennedy School's
Ash Center for Democratic Governance and Innovation; the initiative provides training to mayors and their aides on innovative municipal leadership and challenges facing cities. Since its founding, 275 mayors and more than 400 top city aides have gone through the program, prompting Time Magazine to call Bloomberg "the nation's mayoral tutor". In March 2021, Bloomberg gave Harvard $150 million to create the
Bloomberg Center for Cities to support mayors.
Tobacco, gun control, and public health Bloomberg has been a long-time donor to global
tobacco control efforts. Bloomberg has donated close to $1 billion to the
World Health Organization (WHO) to promote anti-smoking efforts, including $125 million in 2006, $250 million in 2008, and $360 million, making Bloomberg Philanthropies the
developing world's biggest funder of tobacco-control initiatives. Bloomberg's contributions are aimed at "getting countries to monitor tobacco use, introduce strong tobacco-control laws, and create mass media campaigns to educate the public about the
dangers of tobacco use". Bloomberg is the co-founder of
Everytown for Gun Safety (formerly Mayors Against Illegal Guns), a
gun control advocacy group. In 2016, the
World Health Organization appointed Bloomberg as its Global Ambassador for Noncommunicable Diseases.
National September 11 Memorial and Museum In October 2006, Bloomberg became chairman of the board and chief fundraiser of the
National September 11 Memorial & Museum;
CBS News and
Politico credited him with having resolved financial and design obstacles that delayed its completion. He was mayor during the initial planning stages of the memorial & museum. Bloomberg has raised $450 million for the National September 11 Memorial & Museum, including a $50 million personal contribution, making him its largest single donor. Bloomberg secured donations from major corporations by saying they held some responsibility as members of the global community. to which he has donated $130 million. At the ceremony opening for the National September 11 Memorial Museum, Bloomberg said the museum was "a reminder to us and all future generations that freedom carries heavy responsibilities". He continued to lead the annual 9/11 ceremony after leaving office. In September 2021, marking the 20th anniversary of the attacks, Bloomberg and the museum launched The Never Forget Fund, focused on educational programming about 9/11.
Other philanthropy Through Bloomberg Philanthropies, Bloomberg supported the Fresh Air Fund's creation of 'Open Spaces in the City' in summer 2020 to provide socially-distant areas for kids to play during the COVID-19 pandemic, as well as jobs for local teens. He donated $3 million to the construction of a new public library in his hometown of Medford and $75 million for
The Shed, a new arts and
cultural center in
Hudson Yards, Manhattan. In September 2023, the
Perelman Performing Arts Center opened with $130 million of support from Bloomberg, who serves as its chair. The $500 million art center is the final major piece of the redevelopment of the site where the
World Trade Center once stood. Following the
Hamas attack on Israel
in October 2023, Bloomberg committed to matching donations to the Israeli Red Cross, known as
Magen David Adom. By October 19, 2023, Bloomberg had matched $25 million in donations to the ambulance and Medivac services. Bloomberg also endowed his hometown synagogue, Temple Shalom, which was renamed for his parents as the William and Charlotte Bloomberg Jewish Community Center of Medford. Bloomberg hosted the
Global Business Forum in 2017, during the annual meeting of the
United Nations General Assembly; the gathering featured international CEOs, heads of state, and other prominent speakers. In 2009, Bloomberg met with fellow billionaires, including Warren Buffett, Bill Gates, Ted Turner and
Oprah Winfrey, to address issues ranging from the
environment,
health care and concerns over
population growth. Although no formal organization was established, the effort was understood to be designed to help bring various philanthropic projects of the mega-donors into a more unified effort.
Campaign finance controversies In March 2020, during Bloomberg's presidential bid, he was sued by multiple former campaign staffers alleging fraud, and claiming that as many as 2,000 campaign staffers who were promised to be paid through the election were fired instead. == Electoral history ==