Nigeria has been ranked as the most spam-affected country in Africa, with 51 per cent of unknown calls in 2025 identified as spam or fraudulent, according to a new report by caller identification platform Truecaller.

The findings show that more than one in every two unfamiliar phone calls received by users in Nigeria is either unwanted or potentially malicious.

The report places Nigeria 8th globally in spam call prevalence and first in Africa, ahead of South Africa, Kenya, Ghana and Ethiopia.

It noted that while global spam trends are driven largely by scams and financial impersonation, Nigeria’s pattern is dominated by telecom and operator-related outreach, which accounts for about 35 per cent of spam calls.

Telemarketing and sales calls make up around 10 per cent, while outright scam attempts account for about 6 per cent, according to the report.

The structure of unsolicited calls in Nigeria, the report said, creates confusion for users, as legitimate network notifications and marketing messages often overlap with fraudulent attempts.

This blending of communication types makes it difficult for users to distinguish between official messages and potential scams, increasing the risk of either engaging with fraudulent calls or ignoring important ones.

The report also compared Nigeria’s situation with other countries, noting that Brazil shows a similar pattern where telecom-related outreach contributes significantly to spam volumes.

Globally, Indonesia, Chile, Vietnam, Brazil and India were identified as the most spam-affected countries, with some markets recording more than 70 per cent of unknown calls flagged as spam.

Experts warned that the growing volume of spam calls is weakening trust in voice communication, as users increasingly ignore unfamiliar numbers.

This trend, they said, is affecting essential services such as hospitals, schools, delivery companies and financial institutions, which rely on phone calls to reach customers.

Reacting to the report, Chief Executive Officer of Truecaller, Rishit Jhunjhunwala, said the scale of spam and impersonation calls is fundamentally changing how people interact with mobile communication systems.

He noted that efforts are being intensified to curb fraud before it reaches users.

The report also highlighted that Truecaller had surpassed 500 million monthly active users globally as of March 31, 2026, with over 150 million users outside India.