Allegedly laundered $20 billion of Iranian oil and gas revenue from 2012 to 2016 in violation of U.S. sanctions on Iran.

Charged on October 15, 2019 in a six-count indictment with conspiracy to defraud the United States, conspiracy to violate the International Emergency Economic Powers Act (IEEPA), bank fraud, conspiracy to commit bank fraud, money laundering, and conspiracy to commit laundering.

Conspired with Iranian-Turkish businessman Reza Zarrab, who ran a network of front companies in Turkey and the United Arab Emirates and held a contract with Iran's Sarmayeh Exchange; Zarrab accessed Iranian assets at Halkbank, including accounts held by the Central Bank of Iran, the National Iranian Oil Company (NIOC), and the National Iranian Gas Company; used funds to buy gold and falsified records indicating food purchases so that transactions would appear to fall under humanitarian exceptions to U.S. sanctions against Iran; funds were used to make international payments on behalf of the Iranian government, including transfers in U.S. dollars; Naftiran Intertrade Company also held funds in an account at Halkbank.

Senior bank officers participated in the scheme and concealed it from U.S. Treasury officials, including general manager Suleyman Aslan, deputy general manager Mehmet Hakan Atilla, Levent Balkan, and general manager Ali Fuat Taskesenlioglu; high ranking Iranian and Turkish officials were also involved in the scheme, including Turkish Minister of Economic Affairs Mehmet Zafer Caglayan, who took over $70 million in bribes, and then-Prime Minister Recep Tayyip Erdogan; U.S. authorities arrested Zarrab in March 2016 and Atilla in March 2017, charging them along with Caglayan, Aslan, Balkan, Abdullah Happani, Camelia Jamshidy, Mohammad Zarrab, and Hossein Najafzadeh, who remain at large; Zarrab pleaded guilty in October 2017 and testified against Atilla, who was found guilty in May 2018 and sentenced to 32 months in prison, and following his release was appointed to lead Turkey's stock exchange.

Iranian banks involved in facilitating the scheme included Credit Institution for Development, Eghtesad Novin Bank, Bank Keshavarsi, Bank Parsian, Bank Pasargad, Bank Saman, and Bank Sarmayeh (including its front company, Toseh Tejarat); companies that carried out the scheme included Royal Holding, Royal Denizcilik ve Endustriyei Madenler, Safir Altin Ticaret Ithalat Ihracat, Volgam Gida, Mars Kiymetli Madenler ve Gida, Centrica General Trading, Atlantis Capital General Trading, Durak Doviz, and Tasbasi Doviz ve Kiymetli Madenler Ticaret.

Majority-owned by the Turkish government; began offering services in 1938; began opening branches and offering loans to customers in 1950; acquired Tobank in 1992, Sumerbank in 1993, Etibank in 1998, 96 branches of Emlakbank in 2001, and Pamukbank in 2004; privatized 25% of its shares through an IPO in 2007; sold an additional 24% of shares in 2012. As of 2017, operated 963 domestic branches, six foreign branches in Cyprus and Bahrain, and representative offices in London, Tehran, and Singapore.

Conducts consumer and retail banking, corporate and commercial banking, investment banking, and insurance services.

Istanbul Stock Exchange trading symbol is HALKB; SWIFT code is TRHBTR2A; registration number is 862070; MERSIS number is 0456000468500132; DUNS number is 64-329-8060; established in 1933.