Chinese mobile networks have very strict regulations about the time of day and content that can be sent in messages to handsets on their networks. Messages are often randomly selected for manual review, causing delays and possibly a disruption of service. Customers regularly sending messages to China should submit SMS templates of their anticipated message content for whitelisting with local operators.
Due to the tight regulations in China, there are a number of limitations to be aware of:
All messages - even those based on whitelisted templates - will have a “signature” added to the beginning or end of each message.
- This “signature” may vary depending on the partner or route used, but is usually
- Customers with a valid Chinese Business license certificate can register a personalized “signature” for a one-time fee of $75. Please contact our Support team for more information.
Message volume limitations are in place for whitelisted templates:
- Three (3) identical messages submitted to the same number within 24 hours will be rejected.
- Five (5) different messages submitted to the same number within 24 hours will automatically trigger a manual review, and a 24-hour delivery delay.
Message content must mirror confirmed whitelisted templates as strictly as possible.
- Even a small deviation might put traffic at risk of being flagged and delayed or even blocked.
- Any new message content formats would need to be whitelisted first before sending.
Whitelisting Request Process
Message template whitelist requests require the following information:
- The Twilio project Account SID that will be sending these messages
- The proposed message template for whitelisting
Twilio project Account SID
The Twilio project Account SID is the 34 character string that uniquely identifies a Twilio project. The Account SID starts with
AC, and can be found in the Console Project Settings page.
Your template should include a way to identify the company sending the message, and should be relatively uniform from message to message (some content can differ like names, pin codes, dates/times, etc.). Here’s an example template:
Hello [Name], your temporary Twilio PIN code is: 
Once you have collected this information, please contact our Support team and submit your request. We will forward the template to our partners for registration, which usually takes 7-10 business days unless additional information is required. Mobile operators may ask for additional supporting documents like a business license - especially for customers in the financial sector.