The short answer
A marketing message to a customer in the USA costs ₹1.8313 ($0.0250). A utility message — order update, invoice or payment reminder — costs ₹0.2491 ($0.0034). Meta prices the USA and Canada together as one market, “North America” (country code +1). That is about 2.1× the Indian marketing rate of ₹0.8631, so it pays to keep offers to USA customers targeted and send order updates as utility templates.
Meta's prices are per delivered message, set by the message category and the country code of the customer's WhatsApp number. Messages your customers send you are free. With Lead Pattern you pay Meta's rate with zero markup, plus your plan (from ₹15,000 a year).
