Official vs unofficial WhatsApp API: cost, risk and when each one wins

Official (Meta Cloud API): you verify a business, register a dedicated number, and send outside the customer's 24-hour window only with pre-approved templates. Meta charges per delivered message, by category. You get the official channel, a business profile and approved volume.

Unofficial (instance API): you connect a normal number by QR code in minutes, with no business verification and no templates, and send through a REST API. You pay for the number, not the message. The trade-off: it is outside WhatsApp's terms, so the number can be limited or banned.

Brazil, in reais per delivered message, effective October 1, 2026 (Meta's BRL rate card, checked on 26/10/2026):

Meta only changes rates on the first day of a quarter, with a month's notice, and utility and authentication have volume tiers that lower the list rate at high volume. The examples below use list rates. Source: Meta's pricing page.

ZapZap's model, from its pricing page: R$15 per active number per month, prepaid, no per-message fee and no contract lock-in. The first month of each number adds a provisioning fee and the prorated days of the month. Side by side:

Read that table with caution, because it flatters the unofficial side. One number cannot safely send 25,000 messages a month to people who do not know it; the practical limit is how much volume a number can carry before WhatsApp restricts it, not the price. Real operations spread volume across several numbers and warm them up. At 5 numbers the flat price is R$ 75 and at 20 numbers R$ 300, which is a different shape of cost, but not a free lunch. The cost calculator lets you plug in your own volume and category mix.

No unofficial provider can guarantee the safety of your number. Anti-block layers (automatic typing, delays, queueing, warm-up between new numbers) lower the odds. Your list quality and your behavior matter more than any tool. See the anti-ban guide and the acceptable use policy.

Official: business verification, a dedicated number, template approval for anything outside the window. It takes longer to set up. Unofficial: an account, a QR scan and a first message in minutes, and no template approval for free-form text, media, polls or buttons.

The 24-hour window is the part that surprises people. On the official API, once 24 hours pass since the customer's last message, you can only send an approved template. If your use case is mostly replying quickly to people who just wrote, that rule rarely bites. If it is proactive notifications, it is central. The 24-hour window explained covers the cases.

Choose the official API when: you need the official channel, a verified business profile or approved high volume; you send proactive messages to many people (marketing, notifications) and cannot afford a banned number; your compliance team or your customers' terms require a sanctioned channel; or you are a large operation and the per-message cost is small next to the cost of a lost number.

Choose an unofficial API when: you want to start today with a number you already have and test an idea before committing; your traffic is mostly conversations that customers start (support, sales, scheduling), at a modest volume per number; you want predictable cost per number instead of per-message billing; and you accept the ban risk and manage it with opt-in lists, warm-up, human pacing and a dedicated number you can afford to lose.

Neither fixes a bad list. Messaging people who never agreed to hear from you gets numbers banned on either side and raises privacy-law problems (LGPD in Brazil). A side-by-side page with more criteria is at official API vs ZapZap, and the WhatsApp Business API page explains Meta's model in detail. For the full guide on the topic, see also unofficial API: an honest guide.

1) Count how many messages per month are replies to people who wrote first, and how many are proactive. 2) Price the proactive part with Meta's rates (use the table above or the calculator). 3) Ask what a lost number would cost you in leads and history. 4) If the answer is a lot, or you need the sanctioned channel, go official. If you are testing, serving mostly inbound conversations, or want a fixed monthly cost, an instance API is a reasonable starting point, and you can still move to the official API later.

Starting with an unofficial number does not close the door on the official one. Many teams run both: the official API for proactive, high-stakes messages and instances for conversations.

A new ZapZap account gets a welcome credit when the phone is verified (one per phone, subject to the current campaign), so you can connect a test number and send a first message without a deposit. The quick start covers it. Use a number you can afford to lose while you learn how it behaves.