Switch on the account connected to this sender for one channel, so it sends and receives. This is the same switch as Activate on the dashboard's Accounts screen, with the same price and the same limits.

A newly connected account that your plan already includes (nothing charged now, nothing added to the monthly bill) is switched on by itself as soon as it can carry messages. One that would cost money starts inactive: every send on it is refused and it is not listed in the sender's channels until you activate it here or from Accounts, after seeing the price. A connection you switched off stays off.

Billing. Activating is billed as a channel connection. On a paid plan that is one full month charged from the balance at once, and the same amount every month while the connection stays active; the response states both as chargedCents and monthlyCents. The first connections a plan includes cost nothing, and so does re-activating a connection whose current month is already paid. A WhatsApp Business Account is never charged from the balance for its month: one beyond the ones the plan includes is billed on the subscription instead. The exception is a WhatsApp account switched off for non-payment, which settles its past-due fee from the balance when re-activated.

Calling this on a channel that is already active changes nothing and charges nothing. Not available with test-mode keys.

{
  "sender": {
    "id": "sender_12345",
    "name": "Primary sender",
    "phoneNumber": "+13125551212",
    "channels": [
      "sms",
      "voice"
    ],
    "webhook": {
      "url": "https://api.example.com/webhooks/zavu",
      "secret": "whsec_abc123...",
      "signatureVersion": "v2"
    },
    "whatsapp": {
      "displayPhoneNumber": "+14155551234",
      "paymentStatus": {
        "setupStatus": "COMPLETE",
        "methodStatus": "VALID"
      }
    },
    "emailAddress": "noreply@yourdomain.com"
  }
}