How to Set Up WhatsApp Business API in 2026 (Complete Guide)

Collect every artifact Meta will ask for before you ever submit the API form. Centralize it in OnSync's evidence vault.

• Verify Meta Business Manager, billing, and commerce settings.
• Document opt-in proof with screenshots, URLs, and timestamps.
• Pick the phone number, confirm it can receive calls/SMS, and release it from the consumer app.

Submit templates, quality justifications, and the hosting model you chose. Pair the application with a clear launch plan.

• Create Meta Support ticket summarizing use cases, opt-in journey, and compliance contacts.
• Draft first five templates (OTP, welcome, promo) and run them through OnSync linting.
• Decide Cloud API vs BSP; sign the data processing and messaging agreements.

Provision webhooks, API keys, and OnSync's unified inbox so the second Meta approves, conversations land in one place.

• Map webhook events to CRM fields, lifecycle stages, and automations.
• Configure routing rules by queue, skill, language, and time zone.
• Create AI-assisted replies and SLA timers inside OnSync to protect response speed.

Trigger end-to-end rehearsals with staging contacts, QA every template, and rehearse incident responses before scaling volume.

• Send sample notifications through the production number to sandbox devices.
• Validate opt-out commands, sentiment flags, and escalation flows.
• Share go-live timeline with sales, support, and marketing so no rogue blasts occur.