In early October, a wave of cyberattacks, leading to fraud losses, hit several Nigerian banks and financial institutions, potentially costing billions of naira in customer funds, according to several sources with direct knowledge of the matter.
The attacks, the sources noted, affected institutions that rely on external technology providers to run critical financial services, including core banking infrastructure. In one incident, a vendor providing core banking services to financial institutions was reportedly compromised at the system level on October 1. The vendor is one of Africa’s biggest fintech companies.
TechCabal could not immediately establish how many attacks happened, how much money was lost, or whether the incidents were connected. But according to their respective financial reports, three of the country’s biggest banks, Access Holdings Plc, Guaranty Trust Holding Company Plc (GTCO), and Zenith Bank collectively reported ₦2.74 billion ($2.03 million) in fraud losses for the first six months of 2026. GTCO recorded the sharpest year-on-year increase, with fraud losses up by 450.24%.
Data Story The Concentration of Bank Fraud
Three top-tier banks absorbed ₦2.74 billion in fraud losses in just six months, driven by an unprecedented surge at GTCO.
₦30B
₦20B
₦10B
₦25.85B 2025 Industry Total
₦2.74B H1 2026 (Top 3)
GTCO UP 450.24%
Source: NIBSS (2025) & H1 2026 Financial Reports
TechCabal Data
