Definition
In the UAE, the AD prefix is a mandatory "AD-" at the start of the sender ID of every promotional SMS, for example AD-ACME. It marks the message as advertising; transactional senders for OTPs and alerts do not use it.
The rule comes from the UAE regulatory framework set by TDRA and is enforced by the operators etisalat and du. A business that sends both marketing and service messages therefore registers two sender IDs: a promotional one with the AD- prefix and a transactional one without it.
Promotional messages from an AD- sender also have to follow the rest of the UAE marketing rules: verifiable opt-in, an opt-out keyword such as STOP or ايقاف in every message, and no sending between 21:00 and 07:00 UAE time under TDRA's spam policy.
Never send OTPs or account alerts from an AD- sender. They can be delayed by quiet-hour rules, filtered by recipients who block advertising, and they confuse customers about what is important.
Common mistakes: sending promotions from a transactional sender to avoid the prefix (operators can block the sender), and assuming a sender registered for one UAE operator is automatically live on the other. Confirm both during registration.
Example
Sender: AD-ACME — "Weekend sale: 30% off selected items at acme.ae. Reply STOP to opt out."