Twilio WhatsApp

Twilio is a WhatsApp Business Solution Provider (BSP) — an authorized reseller of the official WhatsApp Business Platform. Using Twilio WhatsApp is safe, sanctioned, and fully supported by Meta.

When to use this

• You need zero ban risk.
• You ship customer-critical notifications (OTPs, order confirmations, billing alerts).
• You already use Twilio for SMS or Voice (same console, same billing).
• You want message templates, buttons, and list replies — all the official features.

Pricing

• Trial — free credits.
• Per-message — $0.005 for utility messages, up to $0.05+ for marketing, varies by country.
• Per-conversation — WhatsApp bills in 24-hour conversation windows; Twilio exposes this directly.
• Country-specific pricing: https://www.twilio.com/whatsapp/pricing.

Setup

1. Create a Twilio account at https://twilio.com.
2. Request WhatsApp sender approval — business verification, Meta review, can take days.
3. Use Twilio's sandbox for development (no approval needed) — it's a shared test number you join by messaging a code.
4. Copy Account SID, Auth Token, and your WhatsApp-enabled number.

import "github.com/gopackx/go-notification/channel/whatsapp/twilio"

notifier.RegisterChannel("whatsapp", twilio.New(twilio.Config{
    AccountSID: os.Getenv("TWILIO_ACCOUNT_SID"),
    AuthToken:  os.Getenv("TWILIO_AUTH_TOKEN"),
    From:       "whatsapp:+14155238886", // sandbox or your approved sender
}))

Configuration reference

Sending templates

WhatsApp requires pre-approved templates for business-initiated conversations (marketing, reminders, OTPs sent outside the 24h window). Manage templates in the Twilio Console → WhatsApp → Template Manager.

func (n OTP) ToWhatsApp(u notification.Notifiable) *whatsapp.Message {
    return whatsapp.NewMessage().
        Template("otp_verification", []string{n.Code}). // SID or name, plus variables
        Text("Your code: " + n.Code)                      // fallback text
}

Troubleshooting

• 63007: not an active WhatsApp number — your From isn't approved yet, or sandbox join code wasn't entered by the recipient.
• 63016: template not approved — wait for Meta approval, or the template name has a typo.
• 24-hour window errors — you can only free-text the recipient within 24h of their last inbound message. Outside that, you must use an approved template.
• Cost surprises — marketing category is 5–10× utility. Double-check template categorization before launch.