> ## Documentation Index
> Fetch the complete documentation index at: https://resend.com/docs/llms.txt
> Use this file to discover all available pages before exploring further.

# Batch Sending

> Send up to 100 emails in a single API call.

Batch sending allows you to send multiple emails at once (up to 100) instead of making individual API requests for each email.

## When to use batch sending

Use batch sending when you need to:

* Send multiple transactional emails (e.g., order confirmations and notifications)
* Trigger emails to different recipients with unique content
* Reduce the number of API calls to improve performance

<Note>
  For marketing campaigns, [use our no-code editor,
  Broadcasts](/dashboard/broadcasts/introduction), instead.
</Note>

## Send batch emails

You can send up to 100 emails in a single API call using the batch endpoint. Each email in the batch can have different recipients, subjects, and content.

<CodeGroup>
  ```ts Node.js theme={"theme":{"light":"github-light","dark":"vesper"}}
  import { Resend } from 'resend';

  const resend = new Resend('re_xxxxxxxxx');

  const { data, error } = await resend.batch.send([
    {
      from: 'Acme <onboarding@resend.dev>',
      to: ['delivered@resend.dev'],
      subject: 'Welcome to Acme',
      html: '<p>Thanks for signing up!</p>',
    },
    {
      from: 'Acme <onboarding@resend.dev>',
      to: ['delivered@resend.dev'],
      subject: 'Order Confirmation',
      html: '<p>Your order has been confirmed.</p>',
    },
  ]);

  console.log(data);
  ```

  ```php PHP theme={"theme":{"light":"github-light","dark":"vesper"}}
  $resend = Resend::client('re_xxxxxxxxx');

  $resend->batch->send([
    [
      'from' => 'Acme <onboarding@resend.dev>',
      'to' => ['delivered@resend.dev'],
      'subject' => 'Welcome to Acme',
      'html' => '<p>Thanks for signing up!</p>',
    ],
    [
      'from' => 'Acme <onboarding@resend.dev>',
      'to' => ['delivered@resend.dev'],
      'subject' => 'Order Confirmation',
      'html' => '<p>Your order has been confirmed.</p>',
    ]
  ]);
  ```

  ```py Python theme={"theme":{"light":"github-light","dark":"vesper"}}
  import resend
  from typing import List

  resend.api_key = "re_xxxxxxxxx"

  params: List[resend.Emails.SendParams] = [
    {
      "from": "Acme <onboarding@resend.dev>",
      "to": ["delivered@resend.dev"],
      "subject": "Welcome to Acme",
      "html": "<p>Thanks for signing up!</p>",
    },
    {
      "from": "Acme <onboarding@resend.dev>",
      "to": ["delivered@resend.dev"],
      "subject": "Order Confirmation",
      "html": "<p>Your order has been confirmed.</p>",
    }
  ]

  resend.Batch.send(params)
  ```

  ```rb Ruby theme={"theme":{"light":"github-light","dark":"vesper"}}
  require "resend"

  Resend.api_key = 're_xxxxxxxxx'

  params = [
    {
      "from": "Acme <onboarding@resend.dev>",
      "to": ["delivered@resend.dev"],
      "subject": "Welcome to Acme",
      "html": "<p>Thanks for signing up!</p>",
    },
    {
      "from": "Acme <onboarding@resend.dev>",
      "to": ["delivered@resend.dev"],
      "subject": "Order Confirmation",
      "html": "<p>Your order has been confirmed.</p>",
    }
  ]

  Resend::Batch.send(params)
  ```

  ```go Go theme={"theme":{"light":"github-light","dark":"vesper"}}
  package main

  import (
  	"context"
  	"fmt"

  	"github.com/resend/resend-go/v3"
  )

  func main() {
    ctx := context.TODO()
    client := resend.NewClient("re_xxxxxxxxx")

    var batchEmails = []*resend.SendEmailRequest{
      {
        From:    "Acme <onboarding@resend.dev>",
        To:      []string{"delivered@resend.dev"},
        Subject: "Welcome to Acme",
        Html:    "<p>Thanks for signing up!</p>",
      },
      {
        From:    "Acme <onboarding@resend.dev>",
        To:      []string{"delivered@resend.dev"},
        Subject: "Order Confirmation",
        Html:    "<p>Your order has been confirmed.</p>",
      },
    }

    sent, err := client.Batch.SendWithContext(ctx, batchEmails)

    if err != nil {
      panic(err)
    }
    fmt.Println(sent.Data)
  }
  ```

  ```rust Rust theme={"theme":{"light":"github-light","dark":"vesper"}}
  use resend_rs::types::CreateEmailBaseOptions;
  use resend_rs::{Resend, Result};

  #[tokio::main]
  async fn main() -> Result<()> {
    let resend = Resend::new("re_xxxxxxxxx");

    let emails = vec![
      CreateEmailBaseOptions::new(
        "Acme <onboarding@resend.dev>",
        vec!["delivered@resend.dev"],
        "Welcome to Acme",
      )
      .with_html("<p>Thanks for signing up!</p>"),
      CreateEmailBaseOptions::new(
        "Acme <onboarding@resend.dev>",
        vec!["delivered@resend.dev"],
        "Order Confirmation",
      )
      .with_html("<p>Your order has been confirmed.</p>"),
    ];

    let _emails = resend.batch.send(emails).await?;

    Ok(())
  }
  ```

  ```java Java theme={"theme":{"light":"github-light","dark":"vesper"}}
  import com.resend.*;
  import java.util.Arrays;

  public class Main {
      public static void main(String[] args) {
          Resend resend = new Resend("re_xxxxxxxxx");

          CreateEmailOptions firstEmail = CreateEmailOptions.builder()
              .from("Acme <onboarding@resend.dev>")
              .to("delivered@resend.dev")
              .subject("Welcome to Acme")
              .html("<p>Thanks for signing up!</p>")
              .build();

          CreateEmailOptions secondEmail = CreateEmailOptions.builder()
              .from("Acme <onboarding@resend.dev>")
              .to("delivered@resend.dev")
              .subject("Order Confirmation")
              .html("<p>Your order has been confirmed.</p>")
              .build();

          CreateBatchEmailsResponse data = resend.batch().send(
              Arrays.asList(firstEmail, secondEmail)
          );
      }
  }
  ```

  ```csharp .NET theme={"theme":{"light":"github-light","dark":"vesper"}}
  using Resend;

  IResend resend = ResendClient.Create("re_xxxxxxxxx");

  var mail1 = new EmailMessage()
  {
      From = "Acme <onboarding@resend.dev>",
      To = "delivered@resend.dev",
      Subject = "Welcome to Acme",
      HtmlBody = "<p>Thanks for signing up!</p>",
  };

  var mail2 = new EmailMessage()
  {
      From = "Acme <onboarding@resend.dev>",
      To = "delivered@resend.dev",
      Subject = "Order Confirmation",
      HtmlBody = "<p>Your order has been confirmed.</p>",
  };

  var resp = await resend.EmailBatchAsync([mail1, mail2]);
  Console.WriteLine("Nr Emails={0}", resp.Content.Data.Count);
  ```

  ```bash cURL theme={"theme":{"light":"github-light","dark":"vesper"}}
  curl -X POST 'https://api.resend.com/emails/batch' \
       -H 'Authorization: Bearer re_xxxxxxxxx' \
       -H 'Content-Type: application/json' \
       -d $'[
    {
      "from": "Acme <onboarding@resend.dev>",
      "to": ["delivered@resend.dev"],
      "subject": "Welcome to Acme",
      "html": "<p>Thanks for signing up!</p>"
    },
    {
      "from": "Acme <onboarding@resend.dev>",
      "to": ["delivered@resend.dev"],
      "subject": "Order Confirmation",
      "html": "<p>Your order has been confirmed.</p>"
    }
  ]'
  ```
</CodeGroup>

## Response format

The batch endpoint returns an array of email IDs for successfully created emails.

```json theme={"theme":{"light":"github-light","dark":"vesper"}}
{
  "data": [
    {
      "id": "ae2014de-c168-4c61-8267-70d2662a1ce1"
    },
    {
      "id": "faccb7a5-8a28-4e9a-ac64-8da1cc3bc1cb"
    }
  ]
}
```

If the request fails, the response will include an `error` object with a `message` property. You can find more information about the error in the [Errors](/api-reference/errors) section of the API Reference.

## Limitations

When using batch sending, keep in mind:

* Maximum of **100 emails** per batch request
* The `attachments` field is not supported yet
* The `scheduled_at` field is not supported yet
* Each email in the batch is processed independently
* The request will fail and return an error if any email in your payload is invalid (for example, required fields are missing or fields contain invalid data).

## View batch emails

All emails sent via the batch endpoint appear in the [Emails page](https://resend.com/emails) of your dashboard along with individually sent emails. Each email will have a `queued` status initially before being processed.

## API Reference

For complete API documentation, see the [Send Batch Emails API reference](/api-reference/emails/send-batch-emails).