Once you complete the WhatsApp approval and onboarding process, your Twilio phone number will be enabled for WhatsApp. For these approved and enabled customers, WhatsApp has imposed rate limiting when ramping up your Twilio WhatsApp messaging application.
Due to these rate limits, Twilio recommends customers intending to message with more than 1,000 unique users gradually roll out their WhatsApp launch over the course of a week.
WhatsApp Rate Limits
Here are WhatsApp's rate limit tiers:
|Tier 1||Limited to 1,000 unique message recipients per day|
|Tier 2||Limited to 10,000 unique message recipients per day|
|Tier 3||Limited to 100,000 unique message recipients per day|
Every new WhatsApp-enabled number is initialized at Tier 1. WhatsApp monitors message volume, and will automatically move customers between tiers based on the total number of unique recipients across the past 7 days.
If within the past 7 days, a WhatsApp-enabled Twilio phone number has communicated with 2x the unique recipients of the per-day limit, that number will be automatically moved to the next tier on the next day.
If you exceed the daily limit for your tier, your messages will be undelivered with error 63018.
Notice: Twilio is unable to manually move or request that customers be moved between rate limit tiers. In addition, WhatsApp will not start a number on a higher tier or manually increase the limit at this time.
Example 1: A Twilio phone number approved by WhatsApp begins at Tier 1. On day 1, the number sends to 1,000 unique recipients. On day 2, the number sends to the 1,000 unique recipients again. At the end of day 2, the number would be upgraded to Tier 2 based on having sent to 2,000 unique To numbers within the past 2 days.
Example 2: A Twilio phone number approved by WhatsApp begins at Tier 1. On day 1, the number sends to 50 unique recipients. On day 2, the number sends to 100 unique recipients. On the 3rd day, the number sends to 200 unique recipients. During days 4-7, the number sends messages to 400 unique recipients each day.
At the end of day 7, the number would be upgraded to Tier 2 based on having sent to 2,000 unique To numbers within the past 7 days.