RCS business messaging
Verified businesses can message you in Messages with branding, buttons and rich cards.
Your phone
Carriers
93 carriers offer RCS business messaging on the iPhone 18 Pro Max, and 699 don't.
Questions
Why does RCS business messaging depend on my phone?
Carrier settings differ by phone: Apple ships them per iPhone model. The same carrier can offer a feature on newer phones and not on older ones, or the other way round.
Where do these answers come from?
From the carrier settings shipped for each carrier, read for each iPhone. Some features also need your plan to include them; those show as available.