[2] GTCO Plc's reorganisation means it will now offer more services beyond banking; with a payments business being top of mind for the group.

Guaranty Trust Holding Plc original started as Guaranty Trust Banks, and it was founded in 1988 by over 35 young Nigerians in their thirties, spearheaded mostly by Tayo Aderinokun and Fola Adeola, but also included Femi Pedro, Gbolade Osibodu, Femi Akingbe, Akin Opeodu, and others.

In September 1996, Guaranty Trust Bank plc became a publicly traded corporation and received the President's Merit Award from the Nigerian Stock Exchange.

[8] Guaranty Trust Bank undertook its second share offering in 2004 and raised over ₦11 billion from Nigerian Investors to expand its operations.

[14] Guaranty Trust Bank Limited is a partner of Eko Atlantic City, a newly made island (820 ha.)

In 2013, the Bank issued a US$400,000,000 Euro bond at a coupon rate of 6%; the least obtained by a Nigerian company in the international capital market.

On 29 March 2019, the Supreme Court ordered GT Bank to pay Innoson motors the sum of ₦8.8 billion as a result of an accrued interest.

The other board of directors include; Catherine Echeozo, Suleiman Barau, Helen Lee Bouygues, and Adebanji Adeniyi.

[26] In 2021, Miriam Olusanya was appointed the first female Managing Director of GTBank Nigeria, the flagship company of GTCO Plc.

GTCO PLC has subsidiaries in the following countries: Guaranty Trust Bank has a long history of corporate social responsibility projects,[29] often gaining recognition [29] for its CSR efforts.

In education and sports, Guaranty Trust Bank also hosts the Master's Cup,[31] one of the most popular grassroots football tournaments in the country.

In July 2019, GTBank was recognized as the best bank in Africa at the annual Euromoney Awards for Excellence held in London.