Sender ID
What is Sender ID?
A sender ID is the identifier a recipient sees as the source of a message or call — a phone number, a short code, or, outside the US, an alphanumeric name such as “ORBIT”. Which sender ID types a country allows, and whether they must be pre-registered, is set by each country's carriers and regulators; sending from an unregistered or mismatched sender ID is one of the most common reasons a message gets filtered or blocked entirely.
More detail
In the US and Canada, long-code sender IDs fall under the A2P 10DLC program. Many other countries instead require (or default to) a registered alphanumeric sender ID, and some restrict alphanumeric sender IDs to specific approved use cases.
A sender ID is set per number or per messaging service, and the registration rules differ by destination country — what is valid for one country's traffic may be rejected for another.
Frequently asked
- Can I use my brand name as the sender ID everywhere?
- No. Alphanumeric sender IDs are supported in many countries but not the US or Canada (which use 10DLC long codes instead), and some countries require the alphanumeric ID itself to be pre-registered before it can be used.
- Why was my message delivered from a different number than I sent it from?
- Some destination countries or carriers do not support the sender ID type used, so the platform or carrier substitutes an approved local number or shared short code to get the message delivered.
See also
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