Sending email

Django provides wrappers for Python’s email and smtplib modules to simplify composing and sending email. Django’s email framework also supports swapping in different delivery mechanisms: you can direct email to the console or a file during development, or use community-maintained solutions for sending email directly through commercial email service providers.

The code lives in the django.core.mail module.

Quick examples

Use send_mail() for straightforward email sending. For example, to send a plain text message:

from django.core.mail import send_mail

send_mail(
    "Subject here",
    "Here is the message.",
    "from@example.com",
    ["to@example.com"],
)

When additional email sending functionality is needed, use the EmailMessage or EmailMultiAlternatives class. For example, to send a multipart email that includes both HTML and plain text versions with a specific template and custom headers, you can use the following approach:

from django.core.mail import EmailMultiAlternatives
from django.template.loader import render_to_string

# First, render the plain text content.
text_content = render_to_string(
    "templates/emails/my_email.txt",
    context={"my_variable": 42},
)

# Secondly, render the HTML content.
html_content = render_to_string(
    "templates/emails/my_email.html",
    context={"my_variable": 42},
)

# Then, create a multipart email instance.
msg = EmailMultiAlternatives(
    subject="Subject here",
    body=text_content,
    from_email="from@example.com",
    to=["to@example.com"],
    headers={"List-Unsubscribe": "<mailto:unsub@example.com>"},
)

# Lastly, attach the HTML content to the email instance and send.
msg.attach_alternative(html_content, "text/html")
msg.send()

Configuring email

New Django projects are not configured to send email by default. Instead, email is printed to stdout as a development aid (for projects created with startproject) or results in a MailerDoesNotExist error (when the MAILERS setting isn’t defined).

To enable sending real email, you will need to tell Django how to send it by creating or editing the MAILERS setting. For example, to send through an SMTP server running on the local machine:

MAILERS = {
    "default": {
        "BACKEND": "django.core.mail.backends.smtp.EmailBackend",
        "OPTIONS": {
            "host": "localhost",
        },
    },
}

SMTP is supported by nearly all email service mailers and many hosting environments. But there are other options: many commercial services offer APIs with additional sending features, and during development or testing you might not want to send email at all.

Django abstracts the email sending process into an “email backend” class. Email backends lists the email backends that come with Django: the SMTP backend for production use and several others meant for development and testing. It also covers third-party packages and custom backends if Django’s built-in backends don’t meet your needs.

Django’s test runner automatically overrides the email configuration during testing. It substitutes the memory backend for each defined mailer, preventing email from being sent and giving test cases access to the messages.

Changed in Django Development version:

In earlier releases, Django defaulted to sending email through an SMTP server running on localhost (using the now-deprecated EMAIL_BACKEND and related settings).

Deprecated since version 6.1: Until Django 7.0, if the MAILERS setting is not defined then the earlier behavior still applies: Django will default to using an SMTP server on localhost (but will issue deprecation warnings). Starting in Django 7.0, attempts to send email without MAILERS defined will result in a MailerDoesNotExist error.

Existing projects can opt into the new behavior early by adding MAILERS to settings.py. See Migrating email to mailers.

Multiple mailers

Sometimes different types of email need to be sent in different ways: internal vs. external email, different servers for users in different regions, different services for transactional notifications and bulk marketing email, etc.

The MAILERS setting can define multiple mail configurations. For example:

import os

MAILERS = {
    "default": {
        "BACKEND": "django.core.mail.backends.smtp.EmailBackend",
        "OPTIONS": {
            "host": "smtp.example.net",
            "use_tls": True,
            "username": os.environ["EMAIL_ACCOUNT_ID"],
            "password": os.environ["EMAIL_API_KEY"],
        },
    },
    "notifications": {
        "BACKEND": "example.third.party.EmailBackend",
        "OPTIONS": {
            "api_key": os.environ["THIRD_PARTY_API_KEY"],
            "region": "eu",
        },
    },
    "admin": {
        "BACKEND": "django.core.mail.backends.smtp.EmailBackend",
        "OPTIONS": {
            "host": "localhost",
        },
    },
}

This defines three mailer configurations:

  • "default" sends through an SMTP server at smtp.example.net with a TLS secured connection. It reads an account id and API key from environment variables and uses them as the SMTP authentication username and password. (Many SMTP relay services use some variation of this authentication scheme. Check your provider’s documentation for specific options to use.)

  • "notifications" sends through a hypothetical commercial email service, using a third-party EmailBackend that connects directly to their API. (See Third-party backends for pointers on locating real, community maintained email backend packages.)

  • "admin" sends through an SMTP server running on localhost, with no other options required.

With this configuration, you can provide the using argument to Django’s email sending functions to specify a particular mailer configuration:

from django.core.mail import send_mail

send_mail(
    "Account activated",
    "Congratulations, you're all ready to use our Django app!",
    "from@example.com",
    ["user@example.com"],
    using="notifications",
)

If using is not specified, Django uses the mailer defined for the "default" mailer configuration.

With reusable apps or Django features that send email for you, there may be an option to use a specific mailer. For example, Django’s logging AdminEmailHandler allows specifying the mailer configuration in its using option.

Sending messages

django.core.mail provides functions for conveniently sending email, as well as classes for building and sending more complex email messages with attachments and multiple content types.

Note

The character set of email sent with django.core.mail will be set to the value of your DEFAULT_CHARSET setting.

send_mail()

send_mail(subject, message, from_email, recipient_list, *, fail_silently=False, auth_user=None, auth_password=None, connection=None, html_message=None)[source]

django.core.mail.send_mail() sends a single email message.

The subject, message, from_email and recipient_list parameters are required.

  • subject: A string.

  • message: A string.

  • from_email: A string. If None, Django will use the value of the DEFAULT_FROM_EMAIL setting.

  • recipient_list: A list of strings, each an email address. Each member of recipient_list will see the other recipients in the “To:” field of the email message.

The following parameters are optional, and must be given as keyword arguments if used.

  • fail_silently: A boolean. When it’s False, send_mail() will raise an smtplib.SMTPException if an error occurs. See the smtplib docs for a list of possible exceptions, all of which are subclasses of SMTPException.

  • auth_user: The optional username to use to authenticate to the SMTP server. If this isn’t provided, Django will use the value of the EMAIL_HOST_USER setting.

  • auth_password: The optional password to use to authenticate to the SMTP server. If this isn’t provided, Django will use the value of the EMAIL_HOST_PASSWORD setting.

  • connection: The optional email backend to use to send the mail. If unspecified, an instance of the default backend will be used. See the documentation on Email backends for more details.

  • html_message: If html_message is provided, the resulting email will be a multipart/alternative email with message as the text/plain content type and html_message as the text/html content type.

  • using: An optional MAILERS alias to use to send the mail. If unspecified, the default mailer configuration will be used.

fail_silently, auth_user, auth_password, and connection are not allowed with the using argument.

The return value will be the number of successfully delivered messages (which can be 0 or 1 since it can only send one message).

Deprecated since version 6.0: Passing fail_silently and later parameters as positional arguments is deprecated.

Deprecated since version 6.1: The fail_silently, auth_user, auth_password, and connection arguments are deprecated. In most cases they can be replaced by using with an appropriate MAILERS configuration. See Migrating email to mailers.

Changed in Django Development version:

The using argument was added.

Older versions ignored fail_silently=True, auth_user, and auth_password when a connection was also provided. This now raises a TypeError.

send_mass_mail()

send_mass_mail(datatuple, *, fail_silently=False, auth_user=None, auth_password=None, connection=None, using=None)[source]

django.core.mail.send_mass_mail() is intended to handle mass emailing.

datatuple is a tuple in which each element is in this format:

(subject, message, from_email, recipient_list)

fail_silently, auth_user, auth_password and connection have the same functions as in send_mail(). They must be given as keyword arguments if used, and are not allowed with the using argument.

The keyword argument using is an optional MAILERS alias to use to send the mail. If unspecified, the default mailer configuration will be used.

Each separate element of datatuple results in a separate email message. As in send_mail(), recipients in the same recipient_list will all see the other addresses in the email messages’ “To:” field.

For example, the following code would send two different messages to two different sets of recipients; however, only one connection to the mail server would be opened:

message1 = (
    "Subject here",
    "Here is the message",
    "from@example.com",
    ["first@example.com", "other@example.com"],
)
message2 = (
    "Another Subject",
    "Here is another message",
    "from@example.com",
    ["second@test.com"],
)
send_mass_mail((message1, message2), fail_silently=False)

The return value will be the number of successfully delivered messages.

Deprecated since version 6.0: Passing fail_silently and later parameters as positional arguments is deprecated.

Deprecated since version 6.1: The fail_silently, auth_user, auth_password, and connection arguments are deprecated. In most cases they can be replaced by using with an appropriate MAILERS configuration. See Migrating email to mailers.

Changed in Django Development version:

The using argument was added.

Older versions ignored fail_silently=True, auth_user, and auth_password when a connection was also provided. This now raises a TypeError.

send_mass_mail() vs. send_mail()

The main difference between send_mass_mail() and repeatedly calling send_mail() is that send_mail() opens a connection to the mail server each time it’s executed, while send_mass_mail() uses a single connection for all of its messages. This makes send_mass_mail() slightly more efficient.

send_mail() with multiple to addresses sends a single email message, with john@example.com and jane@example.com both appearing in the “To:” field:

send_mail(
    "Subject",
    "Message.",
    "from@example.com",
    ["john@example.com", "jane@example.com"],
)

send_mass_mail() sends a separate message per datatuple element, so john@example.com and jane@example.com each receive their own email:

datatuple = (
    ("Subject", "Message.", "from@example.com", ["john@example.com"]),
    ("Subject", "Message.", "from@example.com", ["jane@example.com"]),
)
send_mass_mail(datatuple)

mail_admins()

mail_admins(subject, message, *, fail_silently=False, connection=None, html_message=None, using=None)[source]

django.core.mail.mail_admins() is a shortcut for sending an email to the site admins, as defined in the ADMINS setting.

mail_admins() prefixes the subject with the value of the EMAIL_SUBJECT_PREFIX setting, which is "[Django] " by default.

The “From:” header of the email will be the value of the SERVER_EMAIL setting.

This method exists for convenience and readability.

If html_message is provided, the resulting email will be a multipart/alternative email with message as the text/plain content type and html_message as the text/html content type.

The keyword argument using is an optional MAILERS alias to use to send the mail. If unspecified, the default mailer configuration will be used.

Deprecated since version 6.0: Passing fail_silently and later parameters as positional arguments is deprecated.

Deprecated since version 6.1: The fail_silently and connection arguments are deprecated. In most cases they can be replaced by using with an appropriate MAILERS configuration. See Migrating email to mailers.

Changed in Django Development version:

The using argument was added.

Older versions ignored fail_silently=True when a connection was also provided. This now raises a TypeError.

mail_managers()

mail_managers(subject, message, *, fail_silently=False, connection=None, html_message=None, using=None)[source]

django.core.mail.mail_managers() is just like mail_admins(), except it sends an email to the site managers, as defined in the MANAGERS setting.

The keyword argument using is an optional MAILERS alias to use to send the mail. If unspecified, the default mailer configuration will be used.

Deprecated since version 6.0: Passing fail_silently and later parameters as positional arguments is deprecated.

Deprecated since version 6.1: The fail_silently and connection arguments are deprecated. In most cases they can be replaced by using with an appropriate MAILERS configuration. See Migrating email to mailers.

Changed in Django Development version:

The using argument was added.

Older versions ignored fail_silently=True when a connection was also provided. This now raises a TypeError.

The EmailMessage class

Django’s send_mail() and send_mass_mail() functions are actually thin wrappers that make use of the EmailMessage class.

Not all features of the EmailMessage class are available through the send_mail() and related wrapper functions. If you wish to use advanced features, such as BCC’ed recipients, file attachments, or multi-part email, you’ll need to create EmailMessage instances directly.

Note

This is a design feature. send_mail() and related functions were originally the only interface Django provided. However, the list of parameters they accepted was slowly growing over time. It made sense to move to a more object-oriented design for email messages and retain the original functions only for backwards compatibility.

EmailMessage is responsible for creating the email message itself. The email backend is then responsible for sending the email.

For convenience, EmailMessage provides a send() method for sending a single email. If you need to send multiple messages, the email backend API provides an alternative.

class EmailMessage[source]

The EmailMessage class is initialized with the following parameters. All parameters are optional and can be set at any time prior to calling the send() method.

The first four parameters can be passed as positional or keyword arguments, but must be in the given order if positional arguments are used:

  • subject: The subject line of the email.

  • body: The body text. This should be a plain text message.

  • from_email: The sender’s address. Both fred@example.com and "Fred" <fred@example.com> forms are legal. If omitted, the DEFAULT_FROM_EMAIL setting is used.

  • to: A list or tuple of recipient addresses.

The following parameters must be given as keyword arguments if used:

  • cc: A list or tuple of recipient addresses used in the “Cc” header when sending the email.

  • bcc: A list or tuple of addresses used in the “Bcc” header when sending the email.

  • reply_to: A list or tuple of recipient addresses used in the “Reply-To” header when sending the email.

  • attachments: A list of attachments to put on the message. Each can be an instance of MIMEPart or EmailAttachment, or a tuple with attributes (filename, content, mimetype).

    Changed in Django 6.0:

    Support for MIMEPart objects in the attachments list was added.

    Deprecated since version 6.0: Support for Python’s legacy MIMEBase objects in attachments is deprecated. Use MIMEPart instead.

  • headers: A dictionary of extra headers to put on the message. The keys are the header name, values are the header values. It’s up to the caller to ensure header names and values are in the correct format for an email message. The corresponding attribute is extra_headers.

  • connection: An email backend instance. This parameter is ignored when using send_messages().

    Deprecated since version 6.1: The connection argument is deprecated. Instead, define a MAILERS configuration with the desired connection options, and then call EmailMessage.send(using="...") with that configuration’s alias. See Migrating email to mailers.

Deprecated since version 6.0: Passing all except the first four parameters as positional arguments is deprecated.

For example:

from django.core.mail import EmailMessage

email = EmailMessage(
    subject="Hello",
    body="Body goes here",
    from_email="from@example.com",
    to=["to1@example.com", "to2@example.com"],
    bcc=["bcc@example.com"],
    reply_to=["another@example.com"],
    headers={"Message-ID": "foo"},
)

The class has the following methods:

send(fail_silently=False, *, using=None)[source]

Sends the message. Returns 1 if the message was sent successfully, otherwise 0. (An empty list of recipients returns 0 – it will not raise an exception.)

The optional using keyword argument specifies a MAILERS alias to use to send the mail. If not given, the default mailer configuration will be used.

If a deprecated connection was specified when the email was constructed, that connection will be used. Providing both a connection and using will raise an error.

If the deprecated keyword argument fail_silently is True, certain backend-dependent exceptions while sending the message will be ignored. Providing both fail_silently and using will raise an error.

Changed in Django Development version:

The using argument was added.

Older versions ignored fail_silently=True when a connection was also provided. This now raises a TypeError.

Deprecated since version 6.1: The fail_silently argument is deprecated. See Replacing fail_silently for alternatives.

message(*, policy=email.policy.default)[source]

Constructs and returns a Python email.message.EmailMessage object representing the message to be sent.

The keyword argument policy allows specifying the set of rules for updating and serializing the representation of the message. It must be an email.policy.Policy object. Defaults to email.policy.default. In certain cases you may want to use SMTP, SMTPUTF8 or a custom policy. For example, the SMTP email backend uses the SMTP policy to ensure \r\n line endings as required by the SMTP protocol.

If you ever need to extend Django’s EmailMessage class, you’ll probably want to override this method to put the content you want into the Python EmailMessage object.

Changed in Django 6.0:

The policy keyword argument was added and the return type was updated to an instance of EmailMessage.

recipients()[source]

Returns a list of all the recipients of the message, whether they’re recorded in the to, cc or bcc attributes. This is another method you might need to override when subclassing, because the SMTP server needs to be told the full list of recipients when the message is sent. If you add another way to specify recipients in your class, they need to be returned from this method as well.

attach(filename, content, mimetype)[source]
attach(mimepart)

Creates a new attachment and adds it to the message. There are two ways to call attach():

  • You can pass it three arguments: filename, content and mimetype. filename is the name of the file attachment as it will appear in the email, content is the data that will be contained inside the attachment and mimetype is the optional MIME type for the attachment. If you omit mimetype, the MIME content type will be guessed from the filename of the attachment.

    For example:

    message.attach("design.png", img_data, "image/png")
    

    If you specify a mimetype of message/rfc822, content can be a django.core.mail.EmailMessage or Python’s email.message.EmailMessage or email.message.Message.

    For a mimetype starting with text/, content is expected to be a string. Binary data will be decoded using UTF-8, and if that fails, the MIME type will be changed to application/octet-stream and the data will be attached unchanged.

  • Or for attachments requiring additional headers or parameters, you can pass attach() a single Python MIMEPart object. This will be attached directly to the resulting message. For example, to attach an inline image with a Content-ID:

    import email.utils
    from email.message import MIMEPart
    from django.core.mail import EmailMultiAlternatives
    
    message = EmailMultiAlternatives(...)
    image_data_bytes = ...  # Load image as bytes
    
    # Create a random Content-ID, including angle brackets
    cid = email.utils.make_msgid()
    inline_image = email.message.MIMEPart()
    inline_image.set_content(
        image_data_bytes,
        maintype="image",
        subtype="png",  # or "jpeg", etc. depending on the image type
        disposition="inline",
        cid=cid,
    )
    message.attach(inline_image)
    # Refer to Content-ID in HTML without angle brackets
    message.attach_alternative(f'… <img src="cid:{cid[1:-1]}"> …', "text/html")
    

    Python’s email.contentmanager.set_content() documentation describes the supported arguments for MIMEPart.set_content().

    Changed in Django 6.0:

    Support for MIMEPart attachments was added.

    Deprecated since version 6.0: Support for email.mime.base.MIMEBase attachments is deprecated. Use MIMEPart instead.

attach_file(path, mimetype=None)[source]

Creates a new attachment using a file from your filesystem. Call it with the path of the file to attach and, optionally, the MIME type to use for the attachment. If the MIME type is omitted, it will be guessed from the filename. You can use it like this:

message.attach_file("/images/weather_map.png")

For MIME types starting with text/, binary data is handled as in attach().

class EmailAttachment

A named tuple to store attachments to an email.

The named tuple has the following indexes:

  • filename

  • content

  • mimetype

Sending alternative content types

Sending multiple content versions

It can be useful to include multiple versions of the content in an email; the classic example is to send both text and HTML versions of a message. With Django’s email library, you can do this using the EmailMultiAlternatives class.

class EmailMultiAlternatives[source]

A subclass of EmailMessage that allows additional versions of the message body in the email via the attach_alternative() method. This directly inherits all methods (including the class initialization) from EmailMessage.

alternatives

A list of EmailAlternative named tuples. This is particularly useful in tests:

self.assertEqual(len(msg.alternatives), 1)
self.assertEqual(msg.alternatives[0].content, html_content)
self.assertEqual(msg.alternatives[0].mimetype, "text/html")

Alternatives should only be added using the attach_alternative() method, or passed to the constructor.

attach_alternative(content, mimetype)[source]

Attach an alternative representation of the message body in the email.

For example, to send a text and HTML combination, you could write:

from django.core.mail import EmailMultiAlternatives

subject = "hello"
from_email = "from@example.com"
to = "to@example.com"
text_content = "This is an important message."
html_content = "<p>This is an <strong>important</strong> message.</p>"
msg = EmailMultiAlternatives(subject, text_content, from_email, [to])
msg.attach_alternative(html_content, "text/html")
msg.send()
body_contains(text)[source]

Returns a boolean indicating whether the provided text is contained in the email body and in all attached MIME type text/* alternatives.

This can be useful when testing emails. For example:

def test_contains_email_content(self):
    subject = "Hello World"
    from_email = "from@example.com"
    to = "to@example.com"
    msg = EmailMultiAlternatives(subject, "I am content.", from_email, [to])
    msg.attach_alternative("<p>I am content.</p>", "text/html")

    self.assertIs(msg.body_contains("I am content"), True)
    self.assertIs(msg.body_contains("<p>I am content.</p>"), False)
class EmailAlternative

A named tuple to store alternative versions of email content.

The named tuple has the following indexes:

  • content

  • mimetype

Updating the default content type

By default, the MIME type of the body parameter in an EmailMessage is "text/plain". It is good practice to leave this alone, because it guarantees that any recipient will be able to read the email, regardless of their mail client. However, if you are confident that your recipients can handle an alternative content type, you can use the content_subtype attribute on the EmailMessage class to change the main content type. The major type will always be "text", but you can change the subtype. For example:

msg = EmailMessage(subject, html_content, from_email, [to])
msg.content_subtype = "html"  # Main content is now text/html
msg.send()

Preventing header injection

Header injection is a security exploit in which an attacker inserts extra email headers to control the “To:” and “From:” in email messages that your scripts generate.

The Django email functions outlined above all protect against header injection by forbidding newlines in header values. If any subject, from_email or recipient_list contains a newline (in either Unix, Windows or Mac style), the email function (e.g. send_mail()) will raise ValueError and, hence, will not send the email. It’s your responsibility to validate all data before passing it to the email functions.

If a message contains headers at the start of the string, the headers will be printed as the first bit of the email message.

Here’s an example view that takes a subject, message and from_email from the request’s POST data, sends that to admin@example.com and redirects to “/contact/thanks/” when it’s done:

from django.core.mail import send_mail
from django.http import HttpResponse, HttpResponseRedirect


def send_email(request):
    subject = request.POST.get("subject", "")
    message = request.POST.get("message", "")
    from_email = request.POST.get("from_email", "")
    if subject and message and from_email:
        try:
            send_mail(subject, message, from_email, ["admin@example.com"])
        except ValueError:
            return HttpResponse("Invalid header found.")
        return HttpResponseRedirect("/contact/thanks/")
    else:
        # In reality we'd use a form class
        # to get proper validation errors.
        return HttpResponse("Make sure all fields are entered and valid.")
Changed in Django 6.0:

Older versions raised django.core.mail.BadHeaderError for some invalid headers. This has been replaced with ValueError.

Sending many messages efficiently

Establishing and closing an SMTP connection (or any other network connection, for that matter) is an expensive process. If you have a lot of emails to send, it makes sense to reuse an SMTP connection, rather than creating and destroying a connection every time you want to send an email.

There are two ways to tell an email backend to reuse a connection. Both require an email backend instance obtained via get_connection(), which is documented in Email backends.

The first approach is to obtain an email backend instance from mailers and use its send_messages() method. This takes a list of EmailMessage (or subclass) instances, and sends them all using that single connection.

For example, if you have a function called get_notification_emails() that returns a list of EmailMessage objects representing some periodic email you wish to send out, you could send these emails using a single call to send_messages():

from django.core import mail

email_list = get_notification_emails()
# Use the default mailer. You could substitute
# mail.mailers["alias"] for a specific mailer.
backend = mail.mailers.default
backend.send_messages(email_list)

In this example, the call to send_messages() opens a connection on the backend, sends the list of messages, and then closes the connection again. (This is how send_mass_mail() is implemented.)

The second approach is to use the open() and close() methods on the email backend to manually control the connection. send_messages() will not open or close the connection if it is already open, so if you manually open the connection, you can control when it is closed. For example:

from django.core import mail

# Use the "notifications" mailer configuration.
backend = mail.mailers["notifications"]

# Manually open the connection.
backend.open()

# Construct an email message. (Passing None as the third argument
# uses settings.DEFAULT_FROM_EMAIL as the "From:" address.)
email1 = mail.EmailMessage("Hi", "Message", None, ["to1@example.com"])
# Send the email. The connection was already open, so send_messages()
# leaves it open after sending.
backend.send_messages([email1])

# Construct and send two more messages. The connection is still open.
email2 = mail.EmailMessage("Hi", "Message", None, ["to2@example.com"])
email3 = mail.EmailMessage("Hi", "Message", None, ["to3@example.com"])
backend.send_messages([email2, email3])

# Because we opened it, we need to manually close the connection.
backend.close()

When you manually open a backend’s connection, you are responsible for ensuring it gets closed. The example above actually has a bug: if an exception occurs while sending the messages, the connection will not be closed. This can be fixed with a try-finally statement, but using the backend instance as a context manager is preferable, as it automatically calls open() and close() as needed.

This is equivalent to the previous example, but uses the backend as a context manager to avoid leaving the connection open on errors:

from django.core import mail

# Use mail.mailers[...] as a context manager.
with mail.mailers["notifications"] as backend:
    # The backend connection is automatically opened inside the context.
    email1 = mail.EmailMessage("Hi", "Message", None, ["to1@example.com"])
    backend.send_messages([email1])

    # The connection is still open, and is reused for the second send.
    email2 = mail.EmailMessage("Hi", "Message", None, ["to2@example.com"])
    email3 = mail.EmailMessage("Hi", "Message", None, ["to3@example.com"])
    backend.send_messages([email2, email3])

# After exiting the context (either normally or because of an error),
# the backend connection is automatically closed.

Email backends

The actual sending of an email is handled by the email backend.

Django comes with several email backends. With the exception of the SMTP backend, these are mainly useful during testing and development. If the built-in backends don’t meet your needs there are third-party packages available. You can also subclass one of the built-in backends to change its behavior, or even write your own email backend.

The email backend class has the following methods:

  • open() instantiates a long-lived email-sending connection.

  • close() closes the current email-sending connection.

  • send_messages(email_messages) sends a list of EmailMessage objects. If the connection is not open, this call will implicitly open the connection, and close the connection afterward. If the connection is already open, it will be left open after mail has been sent.

It can also be used as a context manager, which will automatically call open() and close() as needed. An example is in Sending many messages efficiently.

SMTP backend

The SMTP email backend connects to an SMTP server to send email. To use it, set BACKEND to "django.core.mail.backends.smtp.EmailBackend".

The SMTP backend supports these OPTIONS:

  • "host" (required): the SMTP server hostname or IP address.

  • "port": the port number to connect to on the SMTP host. If omitted, uses the standard port for the connection protocol depending on the "use_tls" and "use_ssl" options: 587 for TLS, 465 for SSL, or 25 for an unsecured connection.

  • "username" and "password": set these if your server requires SMTP authentication (“SMTP AUTH” credentials, sometimes called SMTP login).

    Although the username is often an email address, it should not be confused with default “From:” addresses. Those are defined by the DEFAULT_FROM_EMAIL and SERVER_EMAIL settings.

  • "use_tls" or "use_ssl": set one of these options to True to connect to the SMTP server using a secure protocol – "use_tls" for explicit TLS or "use_ssl" for SSL (implicit TLS).

  • "ssl_certfile" and "ssl_keyfile": if the SMTP server’s SSL/TLS connection requires client certificate authentication, use these options to specify the paths to a PEM-formatted certificate chain file and private key file. (The key file can be omitted if the certificate file includes the private key.)

    These options are not intended for use with a private certificate authority or self-signed SMTP server certificate. See Private and self-signed SMTP server certificates below.

    Note that these options don’t result in checking certificate validity. They are passed to the underlying SSL connection. Refer to the documentation of Python’s ssl.SSLContext.wrap_socket() method for details on how the certificate chain file and private key file are handled.

  • "timeout": the timeout (in seconds) for connecting to the SMTP server and other blocking operations. If not specified, the value is obtained from socket.getdefaulttimeout(), which defaults to no timeout (None) meaning SMTP operations can block indefinitely.

  • "fail_silently": set to True to ignore certain errors while sending a message. All OSErrors are ignored while opening the SMTP connection, and smtplib.SMTPException errors are ignored while communicating with the server. This will suppress both transient network glitches and also serious configuration problems. However, it does not ignore all errors, and problems with serializing the message will not fail silently. (This option is available for backward compatibility but is not recommended for typical use.)

Example:

MAILERS = {
    "default": {
        "BACKEND": "django.core.mail.backends.smtp.EmailBackend",
        "OPTIONS": {
            "host": "smtp.example.net",
            "use_tls": True,
            "username": "my-app",
            "password": os.environ["MY_APP_SMTP_PASSWORD"],
            "timeout": 10,
        },
    },
}

Deprecated since version 6.1: When the MAILERS setting is not defined, Django uses the SMTP backend as the default mailer (the default EMAIL_BACKEND), connecting to localhost on port 25. This behavior will be removed in Django 7.0, which will not have a default email mailer.

When the SMTP backend is used without MAILERS defined, the options listed above are obtained from the deprecated EMAIL_HOST, EMAIL_PORT, EMAIL_HOST_USER, EMAIL_HOST_PASSWORD, EMAIL_USE_TLS, EMAIL_USE_SSL, EMAIL_SSL_KEYFILE, EMAIL_SSL_CERTFILE, and EMAIL_TIMEOUT settings, respectively. (There is no setting equivalent to the "fail_silently" option.)

class backends.smtp.EmailBackend

Directly instantiating an EmailBackend class is not recommended. Use mailers to obtain a backend instance.

When constructed directly, the SMTP EmailBackend class accepts the options listed above as keyword arguments. Default values come from the corresponding, deprecated EMAIL_* settings. host is not required and defaults to "localhost", and port defaults to 25 even if use_tls or use_ssl is True.

When the MAILERS setting is defined, attempting to directly create an SMTP EmailBackend will raise an AttributeError.

Deprecated since version 6.1: Directly constructing an instance of an EmailBackend class will be unsupported in Django 7.0. Undocumented use will result in different default argument handling compared to earlier releases.

Private and self-signed SMTP server certificates

If the SMTP server uses an SSL certificate from a private certificate authority (CA), the CA’s root certificate should be added to the system CA bundle on the client (where Django is running). Likewise, if the server uses a self-signed certificate, it should be added to the client’s system CA bundle so it can be trusted. (The SMTP backend’s "ssl_certfile" option cannot be used for CA roots or self-signed certificates.)

Follow platform-specific instructions for adding to the system CA bundle. If modifying the system bundle is not possible or desired, an alternative is using OpenSSL’s SSL_CERT_FILE or SSL_CERT_DIR environment variables to specify a custom certificate bundle.

For more complex scenarios, the SMTP backend can be subclassed to add root certificates to its ssl_context using ssl.SSLContext.load_verify_locations().

Console backend

Instead of sending out real emails, the console backend writes the emails that would be sent to the standard output. To use it, set BACKEND to "django.core.mail.backends.console.EmailBackend".

The console backend supports these OPTIONS:

  • "stream": a stream-like object to write to. Defaults to stdout.

  • "fail_silently": set to True to ignore all errors while writing the message to the stream, including errors serializing the message. (This option is available for backward compatibility but is not recommended.)

This backend is not intended for use in production – it is provided as a convenience that can be used during development.

Changed in Django Development version:

The settings file created by startproject now sets up MAILERS with the console backend as the default mailer.

File backend

The file backend writes emails to a file. A new file is created for each new session that is opened on this backend. To use it, set BACKEND to "django.core.mail.backends.filebased.EmailBackend".

The file backend supports these OPTIONS:

  • "file_path" (required): the directory to which the files are written. Can be a string or a pathlib.Path object. If the directory does not exist, the file backend will attempt to create it.

  • "fail_silently": set to True to ignore all errors while writing the message to the file – including errors serializing the message – but not errors related to ensuring the file path directory exists. (This option is available for backward compatibility but is not recommended.)

This backend is not intended for use in production – it is provided as a convenience that can be used during development.

Deprecated since version 6.1: When the file backend is used without the MAILERS setting defined, it will get its file_path option from the EMAIL_FILE_PATH setting.

In-memory backend

The 'locmem' backend stores messages in a special attribute of the django.core.mail module. The outbox attribute is created when the first message is sent. It’s a list with an EmailMessage instance for each message that would be sent. Messages in the outbox are annotated with a sent_using attribute that identifies the MAILERS alias used to send the message.

To use the in-memory backend, set BACKEND to "django.core.mail.backends.locmem.EmailBackend". It does not support any OPTIONS.

Django’s test runner automatically switches to this backend for testing.

This backend is not intended for use in production – it is provided as a convenience that can be used during development and testing.

Changed in Django Development version:

The sent_using attribute was added to messages in the outbox.

Dummy backend

As the name suggests the dummy backend does nothing with your messages. To use it, set BACKEND to "django.core.mail.backends.dummy.EmailBackend". It does not support any OPTIONS.

This backend is not intended for use in production – it is provided as a convenience that can be used during development.

Third-party backends

There are community-maintained solutions!

Django has a vibrant ecosystem. There are email backends highlighted on the Community Ecosystem page. The Django Packages Email grid has even more options for you!

Third-party email backends are available that:

  • Integrate directly with commercial email service providers’ APIs (which often have extra functionality not available through SMTP).

  • Offload email sending to asynchronous task queues.

  • Add features to other email backends, such as enforcing do-not-send lists or logging sent messages.

  • Provide development and debugging tools, such as sandbox capture and in-browser email previews.

Defining a custom email backend

If you need to change how emails are sent you can write your own email backend. To use a custom backend, set BACKEND to the Python import path for your backend class and OPTIONS to any __init__() keyword arguments your backend supports.

Custom email backends should subclass BaseEmailBackend that is located in the django.core.mail.backends.base module. A custom email backend must implement the send_messages(email_messages) method. This method receives a list of EmailMessage instances and returns the number of successfully delivered messages. If your backend has any concept of a persistent session or connection, you should also implement the open() and close() methods. Refer to smtp.EmailBackend for a reference implementation.

Obtaining an instance of an email backend

The mailers factory in django.core.mail returns instances of email backends.

mailers

You can access the mailers configured in the MAILERS setting through a dict-like object: django.core.mail.mailers:

>>> from django.core.mail import mailers
>>> mailers["notifications"]

If the named key is not defined, a MailerDoesNotExist error will be raised. Other configuration problems will raise an InvalidMailer error.

New in Django Development version.
mailers.default

As a shortcut, the default mailer can be accessed through django.core.mail.mailers.default:

>>> from django.core.mail import mailers
>>> mailers.default

This is equivalent to mailers["default"]. If no default mailer has been configured, a MailerDoesNotExist error will be raised.

Deprecated since version 6.1: If the MAILERS setting is not defined, mailers.default will create an email backend instance from the deprecated EMAIL_BACKEND and related settings. This supports backward compatibility with Django 6.0 and earlier.

This behavior (and those settings) will be removed in Django 7.0.

get_connection(backend=None, *, fail_silently=False, **kwargs)[source]

The deprecated django.core.mail.get_connection() function creates and returns an instance of an email backend. Its behavior depends on the MAILERS setting and how the function is called.

If the MAILERS setting is defined:

  • get_connection() with no arguments will return mailers.default.

  • get_connection(...) called with only fail_silently or other keyword arguments will create an instance of MAILERS["default"] with any keywords added to the default mailer’s OPTIONS.

  • get_connection(backend, ...) with a backend import path will raise an error.

If the MAILERS setting is not defined:

  • get_connection() with no arguments will return an instance of the email backend specified in EMAIL_BACKEND.

  • If you specify the backend argument, an instance of that backend will be instantiated.

  • If the keyword argument fail_silently is True, certain backend-dependent exceptions during the email sending process will be silently ignored.

  • All other keyword arguments are passed directly to the constructor of the email backend.

Deprecated since version 6.0: Passing fail_silently as positional argument is deprecated.

Deprecated since version 6.1: get_connection() is deprecated and will be removed in Django 7.0. Switch to mailers[alias]. See Replacing get_connection() and connection arguments for migration suggestions.

Configuring email for development

There are times when you do not want Django to send emails at all. For example, while developing a website, you probably don’t want to send out thousands of emails – but you may want to validate that emails will be sent to the right people under the right conditions, and that those emails will contain the correct content.

The easiest way to configure email for local development is to use the console email backend. This backend redirects all email to stdout, allowing you to inspect the content of mail.

The file email backend can also be useful during development – this backend dumps the contents of every SMTP connection to a file that can be inspected at your leisure.

Another approach is to use a mocked SMTP server that receives the emails locally and displays them to the terminal, but does not actually send anything. The aiosmtpd package provides a way to accomplish this:

python -m pip install "aiosmtpd >= 1.4.5"

python -m aiosmtpd -n -l localhost:8025

This command will start a minimal SMTP server listening on port 8025 of localhost. This server prints to standard output all email headers and the email body. You then only need to set an SMTP backend’s "host" and "port" OPTIONS accordingly. For a more detailed discussion of SMTP server options, see the documentation of the aiosmtpd module.

For information about unit-testing the sending of emails in your application, see the Email services section of the testing documentation.