Multiple recipients

The to parameter of sendEmail accepts either a single string or an array of strings. When you pass an array, every recipient sees the full To list. This is appropriate for team notifications, shared updates, and other messages where recipients know each other.

Passing multiple recipients

const result = await client.sendEmail(
  ["alice@example.com", "bob@example.com", "charlie@example.com"],
  "Team standup notes",
  { text: "Notes from today's standup are attached." }
);

How arrays are serialized

The SDK joins array values differently depending on whether the request uses JSON or multipart:

Transport	Join separator	Example
JSON (no attachments)	`,` (comma, no space)	`"alice@example.com,bob@example.com"`
Multipart (with attachments)	`,` (comma + space)	`"alice@example.com, bob@example.com"`

Single string values are passed as-is in both cases. The API handles the final delivery.

Validation

The SDK validates to before sending:

It must be a non-empty string after trimming, or a non-empty array.
Every array element must be a non-empty string after trimming.

If validation fails, the method returns { success: false, errorMessage: "'to' must contain at least one recipient" } with no statusCode.

The SDK does not validate email address format. The API validates addresses and enforces recipient limits server-side. The exact maximum number of recipients per message is not published by BosonWare. Contact support@bosonware.com to confirm your plan’s limits.

When to send individual emails instead

If recipients should not see each other’s addresses, or if you need per-recipient customization, loop over the list and call sendEmail once per recipient. This also gives you per-recipient Result objects and messageId values for tracking.

send-individual.ts

import BosonMailClient from "@bosonware-ent/bosonmail";

const client = new BosonMailClient({ apiKey: process.env.BOSONMAIL_API_KEY! });

const recipients = ["alice@example.com", "bob@example.com", "charlie@example.com"];

for (const recipient of recipients) {
  const result = await client.sendEmail(
    recipient,
    "Your personalized report",
    { text: `Hi, here is your report for this week.` }
  );

  if (result.success) {
    console.log(`Sent to ${recipient}: messageId=${result.messageId}`);
  } else {
    console.error(`Failed to ${recipient}:`, result.errorMessage);
  }
}

Individual sends give you per-recipient status tracking via messageId, but each message counts against your plan’s outbound allowance. Confirm with BosonWare whether API sends through the SDK count toward your inbox’s 500 outbound emails per month.

CC and BCC with multiple recipients

You can combine multiple to recipients with cc and bcc. See CC and BCC for full details on how each field behaves and how arrays are serialized.

const result = await client.sendEmail(
  ["team-a@example.com", "team-b@example.com"],
  "Project update",
  {
    text: "The project is on track.",
    cc: "manager@example.com",
    bcc: ["archive@example.com", "audit@example.com"]
  }
);

CC and BCC

How CC and BCC fields work with single and multiple recipients.

Sending emails

Full sendEmail reference with all parameters and validation rules.

Email status

Track delivery for each messageId after sending.

Guides: Multiple recipients

Practical guide for batch and individual sending patterns.

Getting Started

SDK Reference

Guides

Advanced

Resources

Passing multiple recipients

How arrays are serialized

Validation

When to send individual emails instead

CC and BCC with multiple recipients

CC and BCC

Sending emails

Email status

Guides: Multiple recipients

​Passing multiple recipients

​How arrays are serialized

​Validation

​When to send individual emails instead

​CC and BCC with multiple recipients

CC and BCC

Sending emails

Email status

Guides: Multiple recipients

Passing multiple recipients

How arrays are serialized

Validation

When to send individual emails instead

CC and BCC with multiple recipients