SMS Sender IDs and how they can be faked

Why a text message showing a brand name as its sender is not proof the brand actually sent it.

By AlertaSpam Security Team. Published August 7, 2026

An 'alphanumeric Sender ID' is a text label — like a brand name — that a business can register with a messaging provider to appear instead of a phone number. It exists to make legitimate business texts more recognizable, but the verification behind it varies a great deal by country and carrier.

In markets with weak or no registration checks, anyone can often set an arbitrary Sender ID through certain bulk-SMS gateways, which is why a message showing your bank's name can still be fraudulent. This is why AlertaSpam records SMS sender pages with an explicit note that the name can be spoofed, rather than treating the name as a verified source.

Some countries have introduced Sender ID registries or protection schemes — the UK's Mobile Ecosystem Forum registry and Singapore's SMS Sender ID Registry are examples — which reduce but do not eliminate the risk, and mainly apply to senders operating within that country's telecom rules.

Treat the Sender ID as a hint, not a verification. Judge the message on its content and links, and when a text claims urgency around money or credentials, verify it through the organization's official app or website instead.