DTB Kenya was incorporated in 1946 as the Diamond Jubilee Investment Trust (DJIT) to commemorate the Diamond Jubilee of the ascension to the Imamat by the late Aga Khan III. DJIT’s shares were subscribed by the Ismaili Community as well as the Aga Khan.

In 1972, the name was changed to Diamond Trust of Kenya (DTK).It acquired a much wider public profile, transforming itself from a community based finance house into a non-bank financial institution (NBFI) serving the general Kenyan public. In the same year, it was floated on the Nairobi Stock Exchange through an IPO. Currently it has approximately 11,500 shareholders. In 1983, International Finance Corporation (IFC) who took up 10% equity interest in DTK. In 1986, the shares held by the Aga Khan and members of his family in DTB Kenya were consolidated under the Aga Khan Fund for Economic Development (AKFED); this shareholding currently stands at 17.3%. In 1995, banking operations in Uganda were revived by injecting capital in the operation. DTK and AKFED increased its shareholding to 27% and 33% respectively. In Tanzania, similar injection of capital was made with DTB Kenya and AKFED taking up 33% and 31% shareholding respectively. More recently, in June 2007 and October 2008, Diamond Trust Bank Tanzania and Diamond Trust Bank Uganda, respectively, undertook a US$ 4.2 million and a US$ 3 million rights issue respectively. DTB Kenya took up its rights as well as the shareholding and rights of some other shareholders. Following this development, DTB Kenya now has a 55% shareholding in DTB Tanzania and a 51% shareholding in DTB Uganda, making both DTB Kenya’s subsidiaries. After years of operating as a non bank financial institution, in 1997, DTK acquired a licence to conduct commercial banking business and changed its name to Diamond Trust Bank Kenya Limited (DTB Kenya). It commenced commercial banking services in July 1997, offering a full range of services targeting principally small and mid sized corporates. Diamond Trust Tanzania and Diamond Trust Uganda were also converted from NBFIs to commercial banks and renamed Diamond Trust Bank Tanzania Limited (DTB Tanzania) and Diamond Trust Bank Uganda Limited (DTB Uganda). In 2003, DTB Kenya started offering money transfer services to the unbanked community in Kenya under arrangement with Western Union (WU). In 2004, the bank broadened its banking service by introducing retail banking to optimise on the opportunities in the retail banking market; retail banking products were rolled out under a phased programme in Kenya and from 2008 in Tanzania and Uganda. In 2006 and 2007, DTBK increased its capital base through two successive rights issue offerings both of which were heavily subscribed. Through the two issues the bank raised KShs 2.4 billion (US$ 30 million). In late 2008, DTB Kenya established a commercial banking subsidiary in Burundi, Diamond Trust Bank Burundi S.A. DTB Kenya hold 67% of the equity in the Burundi operation, which commenced banking business in June 2009. Presently, DTBK operates as a medium size commercial bank in Kenya, offering banking product and services to small and medium size customers, including corporates, SMEs and the consumer banking customers. In Tanzania, DTB is a medium size bank with a balance sheet footing of US$ 122.5 million and pre-tax profit of US$ 3.1 million in 2008. The Uganda operation is a small size commercial banking business; balance sheet of US$ 75 million and pre-tax profit of US$ 1.2 million in 2008.