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Configure send bindings

When you add a send_email binding to a Worker, you can restrict which addresses it may send from and to. Configure these restrictions in your Wrangler configuration file. For the binding API itself, refer to the Workers API.

Binding types

Each entry in send_email can be configured to restrict what the binding can do. The sender address must always belong to a domain you have onboarded to Email Service.

  • No restriction attribute: The binding can send to any verified destination address in your account.
  • destination_address: The binding can only send to the single destination address configured here. If you call send() with to set to null or undefined, the configured address is used.
  • allowed_destination_addresses: The binding can only send to addresses listed in this allowlist.
  • allowed_sender_addresses: The binding can only send from the addresses listed in this allowlist.
JSONC
{
  "send_email": [
    // Send to any verified destination
    { "name": "EMAIL" },
    // Send only to a single fixed destination
    {
      "name": "NOTIFY_OPS",
      "destination_address": "ops@yourdomain.com",
    },
    // Send only to addresses on an allowlist
    {
      "name": "EMAIL_TEAM",
      "allowed_destination_addresses": [
        "alice@yourdomain.com",
        "bob@yourdomain.com",
      ],
    },
    // Send only from addresses on an allowlist
    {
      "name": "RESTRICTED_EMAIL",
      "allowed_sender_addresses": [
        "noreply@yourdomain.com",
        "support@yourdomain.com",
      ],
    },
  ],
}

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