What it means
Every WhatsApp Business API number has a rolling quality rating: Green (high), Yellow (medium), or Red (low). Meta calculates it from how recipients react to your messages over the past 7 days. Blocks, reports as spam, and message-block actions all push the rating down. Healthy engagement keeps it Green.
The rating is visible in your Meta Business Manager and changes daily. New numbers start without a rating; one builds up over the first weeks of sending.
Why it matters
Quality rating directly affects your messaging tier (the daily cap on how many unique users you can message). A Green rating lets you climb tiers fast and reach unlimited daily volume. A Red rating freezes you at your current tier and threatens permanent number suspension.
Most quality drops trace back to one thing: sending marketing templates to people who did not opt in, or who barely remember your brand. Tight opt-in collection and good list hygiene are the cheapest insurance against rating drops.
Example
An e-commerce brand blasts a Black Friday template to 8,000 contacts including dormant ones from three years back. Block rate spikes. Quality drops to Red the next day, freezing them at the 1,000-conversation tier just as their busiest week begins. The lesson: the next campaign goes only to engaged contacts (around 2,000), the rating recovers within two weeks, and tier expansion resumes.