Plain answers about SMS short codes
Who is texting you from five digits?
What the short numbers behind bank alerts, sign-in codes and delivery texts are, the rules every sender has to keep, and how to find out who is behind one.
In short
A short code is a phone number of five or six digits that exists only for text messages. Businesses, banks, charities, campaigns and public agencies in the United States lease these numbers so they can reach many people at once, and the wireless carriers review every program before it may send a single message. The Five-Digit Desk answers what people tend to wonder once such a number shows up on their phone, and what a small sender wonders before renting one.
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What the desk answers
A short code on its own does not show that a message is honest, and scam texts copy the wording of real ones. The Federal Trade Commission’s advice is plain: a text that asks for personal or financial details gets no clicks, a company that may really be writing is contacted through a number or website already known to be its own, and spam can be copied to 7726, the number the carriers use to collect it, or reported at ReportFraud.ftc.gov.
Most of these texts were requested at some point, often without much thought: a sign-in code from an app, a shipping update, a low-balance warning from a bank, a reminder that a prescription is ready. Others follow a keyword someone texted after seeing it on a poster, or a phone number typed in at a checkout. When a message comes from a code nobody remembers agreeing to, two replies work on any legitimate program. HELP brings back the sender’s name and a way to contact it. STOP ends the messages. Carrier rules oblige every short code program to answer both. The same order holds for lenders outside the United States: in Peru, Wandoo texts an applicant its decision and, later, a reminder before the payment falls due, both answers to something the borrower started.
Questions covers the groundwork: what a short code is, how keywords work, what leasing a code cost and why some phones never receive these texts. Rules and compliance sets out what the carriers demand from anyone sending from a short code, which is also what a recipient can expect. Code notes looks at particular numbers, and its main page explains how to find out who is behind a code, with a table of widely used codes and their owners as of 2016.
No page here searches anything as you read it, and the site keeps no list of numbers beyond what its pages print. Every page is dated, and the prices and rules it describes belong to that date. The archive sets them all out in order.
Three sections
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Questions
The groundwork, for people who receive short code texts and people who send them.
5 answers, 2016
Rules and compliance
The conditions that come with sending from a short code.
1 page, 2016
Code notes
Particular numbers, and how to trace the sender behind any of them.
3 notes, 2016