In a significant security move, telecommunications giant Three Mobile has dispatched an urgent warning message to its entire customer base of over 10 million people across the United Kingdom. The network, one of Britain's prominent 'big four' mobile providers, has taken proactive steps to protect its users from increasingly sophisticated financial fraud attempts.
Critical Security Guidance for Customers
The company's message contains clear, direct instructions for customers who might encounter suspicious communications. Three Mobile explicitly states that legitimate company representatives will never contact customers to request their One-Time Passcodes (OTPs). The only exception occurs when customers themselves initiate contact with Three directly through official channels.
Recognising Fraudulent Approaches
The warning elaborates on common tactics employed by fraudsters, who may contact customers through various means including telephone calls and social media platforms. These criminals often pose as Three Mobile representatives, sometimes offering tempting incentives such as substantial discounts on current price plans to lower victims' defences before requesting sensitive security codes.
Three Mobile's official guidance states: "If someone contacts you by phone or social media claiming to be from Three, please do not share any OTP that we send to you via text or email. Fraudsters may be attempting to access your account and may try to tempt you with a large discount on your current price plan before asking for the code."
Reporting Suspicious Activity
The telecommunications provider has established straightforward reporting mechanisms for customers who encounter potentially fraudulent communications. For suspicious text messages, customers should forward the message to the shortcode 7726. When dealing with suspicious telephone calls, users are instructed to text the word "CALL" followed by the suspicious number to the same 7726 reporting service.
Security Context and Network Performance
This security alert arrives alongside recent performance rankings that position Three Mobile as the United Kingdom's fastest 5G network. According to comprehensive testing conducted by Ookla during the third and fourth quarters of 2025, Three achieved an impressive average download speed of 214Mbps. This performance significantly outpaces competitors, being more than 80Mbps faster than its nearest rival and approximately twice as fast as the UK's average fixed-line broadband speed.
Ookla's verification confirms Three Mobile's network superiority, stating: "3 is the Fastest 5G Network in the United Kingdom, Q3–Q4 2025. The Speedtest Award for Fastest Network is based on Speed Score and provides a measure of a network's throughput and responsiveness. It combines download and upload speeds with latency metrics to give an overall view of speed performance."
The recent rankings placed Vodafone in second position, followed by EE in third, while O2 occupied the bottom position across all measured categories, delivering the slowest overall speeds among the major UK networks.
Broader Implications for Consumer Protection
This proactive security communication from Three Mobile highlights the growing sophistication of telecommunications fraud in the digital age. As mobile networks become increasingly central to people's financial lives and personal data security, such warnings serve as crucial reminders about maintaining digital vigilance. The company's decision to communicate directly with its entire customer base demonstrates a commitment to consumer protection beyond mere service provision, acknowledging the shared responsibility between providers and users in maintaining secure digital environments.
