SMS guidelines for Mexico

You cannot send SMS to a landline destination number: the Twilio REST API will throw a 400 response with error code 21614, the message will not appear in the logs, and the account will not be charged.

You must not use SMS as a marketing or research tool in Mexican elections. Carriers will block any numbers used to promote a particular political candidate or cause.

Mexico has a unique dialing plan. When texting a mobile number, you must use the following format: "+52" + "1" + area code + subscriber number An example number is: +5215512345678

You should not use Mexican mobile numbers to send marketing, 1-way, or application-to-person (A2P) traffic. URLs and brand names are some of the A2P content likely to be blocked when sending from Mexican numbers.

Twilio strongly encourages customers to review proposed use cases with qualified legal counsel to ensure they comply with all applicable laws. The following are some general best practices:

1. Get opt-in consent from each end user before sending any communication to them, particular for marketing or other non-essential communications.
2. Only communicate during an end user's daytime hours unless it is urgent.
3. SMS campaigns should support HELP/STOP messages, and similar messages, in the end user's local language.
4. Do not contact end users on do-not-call or do-not-disturb registries.