There are a couple of ways to look at thisâthere are capacity limits, which restrict the number of messages you can send to the API endpoint. That comes to 50 requests per second, with some flexibility built in for heavy bursts of up to 150 per second.
Meanwhile, the actual number of messages you can send as a business is limited by tier. Tier 1 means being able to send messages to up to 1,000 unique customers, and then it multiplies by a factor of 10 as you move up tiers: 10,000 for tier 2, and 100,000 for tier 3. Remember, the higher the tier, the lower the cost-per-message.