WhatsApp Business API vs Mossmoon.

The WhatsApp Business API is Meta's official server-side product. You (or a BSP reselling it, like Twilio or 360dialog) register a business, verify it with Meta, and message through Meta's infrastructure under Meta's commercial rules: template pre-approval, the 24-hour customer service window, and per-conversation billing.

Mossmoon doesn't touch the Business API. Your customer scans a QR with the normal WhatsApp on their phone, and a hosted always-on connection makes that number programmable. No Meta onboarding, no templates, no 24-hour window, no per-message fees. The trade-off: it's built for real one-to-one conversations, not mass one-to-many broadcast.

Business API: per-conversation fees set by Meta that vary by country and message category (marketing conversations cost more than utility ones), usually plus a BSP's platform fee on top. A support-heavy month in Brazil and a quiet month in the US can produce wildly different bills.

Mossmoon: $15 per line per month flat, or $20 with voice calling enabled. Unlimited inbound and outbound. Your bill is the number of active lines times a number you already know. Run your own numbers in the cost calculator; at very low volume the Business API can genuinely be cheaper, and the calculator will tell you so.

Business API: Meta business verification takes days to weeks per business, plus display-name review, plus template approval before your first proactive outbound. Onboarding a client means walking them through Meta Business Manager.

Mossmoon: POST one API call, put the QR in front of your customer, they scan, the line is live. Under two minutes end to end. First line is free for 7 days, and the trial starts when the QR is scanned, not when you sign up.

On the Business API, you can only message a user freely for 24 hours after their last message. After that, every outbound must be a pre-approved template in an approved category. This is the single constraint that breaks most conversational use cases: the day-3 follow-up, the reschedule nudge, the 'did that fix it?' check-in.

Mossmoon has no window and no templates, because those are Business API policies and the connection isn't the Business API. Send what a human would send, when a human would send it.

Three cases, honestly: one-to-many broadcast at scale (promotional blasts to opted-in lists are what templates and per-message pricing were designed for); the official green-checkmark business presence, if your brand requires it; and organizations whose compliance teams specifically require Meta's official commercial channel.

If that's you, use the Business API for that workload. Plenty of teams run both: Business API for broadcast campaigns, Mossmoon for the two-way conversations the window keeps killing.

WhatsApp's terms are written around the account owner using their own account, and the always-on connection is authorized by the owner scanning from their own phone, the same flow WhatsApp ships for connecting any additional device. What gets numbers flagged is behavior: unsolicited mass messaging gets any WhatsApp account banned, Business API or not.

Mossmoon enforces the healthy pattern on purpose: outbound rate limits, burst throttling, and refusal of blast-shaped traffic. Used for real conversations, lines stay healthy long-term.

Yes, in either direction, because both sides are just REST APIs and webhooks from your application's point of view. Teams most often start on Mossmoon (live today, zero onboarding), and add the Business API later if a broadcast use case appears.

Your integration code barely changes: swap the send endpoint and the webhook parser. The bigger migration cost is on the Business API side, where every new customer still has to clear Meta verification.