diff --git a/README.md b/README.md
index d846d486..b8530135 100644
--- a/README.md
+++ b/README.md
@@ -241,6 +241,7 @@ To generate coverage reports for the Javascript tests:
 - `MAIL_SENDER`: String. Email address to send outgoing mail from.
 - `MAIL_SERVER`: The SMTP host
 - `MAIL_TLS`: Boolean. Use TLS to connect to the SMTP server.
+- `MICROSOFT_TASK_ORDER_EMAIL_ADDRESS`: String. Email address for Microsoft to receive PDFs of new and updated task orders.
 - `PERMANENT_SESSION_LIFETIME`: Integer specifying how many seconds a user's session can stay valid for. https://flask.palletsprojects.com/en/1.1.x/config/#PERMANENT_SESSION_LIFETIME
 - `PGDATABASE`: String specifying the name of the postgres database.
 - `PGHOST`: String specifying the hostname of the postgres database.
diff --git a/atst/utils/mailer.py b/atst/utils/mailer.py
index a67a851b..a5dbfc0b 100644
--- a/atst/utils/mailer.py
+++ b/atst/utils/mailer.py
@@ -1,5 +1,6 @@
 from contextlib import contextmanager
 import smtplib
+import io
 from email.message import EmailMessage
 
 
@@ -76,8 +77,34 @@ class Mailer(object):
 
         return msg
 
-    def send(self, recipients, subject, body):
+    def _add_attachment(self, message, content, filename, maintype, subtype):
+        with io.BytesIO(content) as bytes_:
+            message.add_attachment(
+                bytes_.read(), filename=filename, maintype=maintype, subtype=subtype
+            )
+
+    def send(self, recipients, subject, body, attachments=[]):
+        """
+        Send a message, optionally with attachments.
+        Attachments should be provided as a list of dictionaries of the form:
+        {
+            content: bytes,
+            maintype: string,
+            subtype: string,
+            filename: string,
+        }
+        """
         message = self._build_message(recipients, subject, body)
+        if attachments:
+            message.make_mixed()
+            for attachment in attachments:
+                self._add_attachment(
+                    message,
+                    content=attachment["content"],
+                    filename=attachment["filename"],
+                    maintype=attachment.get("maintype", "application"),
+                    subtype=attachment.get("subtype", "octet-stream"),
+                )
         self.connection.send(message)
 
     @property
diff --git a/config/base.ini b/config/base.ini
index 71081e83..1f4c732a 100644
--- a/config/base.ini
+++ b/config/base.ini
@@ -26,6 +26,7 @@ MAIL_PORT
 MAIL_SENDER
 MAIL_SERVER
 MAIL_TLS
+MICROSOFT_TASK_ORDER_EMAIL_ADDRESS = example@example.com
 PERMANENT_SESSION_LIFETIME = 1800
 PGDATABASE = atat
 PGHOST = localhost
diff --git a/tests/conftest.py b/tests/conftest.py
index 8c22ddc3..03d07a12 100644
--- a/tests/conftest.py
+++ b/tests/conftest.py
@@ -164,6 +164,12 @@ def pdf_upload2():
         yield FileStorage(fp, content_type="application/pdf")
 
 
+@pytest.fixture
+def downloaded_task_order():
+    with open(PDF_FILENAME, "rb") as fp:
+        yield {"name": "mock.pdf", "content": fp.read()}
+
+
 @pytest.fixture
 def extended_financial_verification_data(pdf_upload):
     return {
diff --git a/tests/utils/test_mailer.py b/tests/utils/test_mailer.py
index 8b40ea48..41c68434 100644
--- a/tests/utils/test_mailer.py
+++ b/tests/utils/test_mailer.py
@@ -1,10 +1,17 @@
 import pytest
-from atst.utils.mailer import Mailer, Mailer, MailConnection, RedisConnection
+from atst.utils.mailer import (
+    Mailer,
+    MailConnection,
+    RedisConnection,
+)
+from atst.utils.localization import translate
+from email.mime.base import MIMEBase
 
 
 class MockConnection(MailConnection):
     def __init__(self):
         self._messages = []
+        self.sender = "mock@mock.com"
 
     def send(self, message):
         self._messages.append(message)
@@ -46,3 +53,55 @@ def test_redis_mailer_can_save_messages(app):
     assert message_data["recipients"][0] in message
     assert message_data["subject"] in message
     assert message_data["body"] in message
+
+
+def test_send_with_attachment(app, mailer, downloaded_task_order):
+    to_number = "11111111111111"
+    attachment = {
+        "maintype": "application",
+        "subtype": "pdf",
+        "filename": downloaded_task_order["name"],
+        "content": downloaded_task_order["content"],
+    }
+    mailer.send(
+        recipients=[app.config["MICROSOFT_TASK_ORDER_EMAIL_ADDRESS"]],
+        subject=translate("email.task_order_sent.subject", {"to_number": to_number}),
+        body=translate("email.task_order_sent.body", {"to_number": to_number}),
+        attachments=[attachment],
+    )
+    # one email was sent
+    assert len(mailer.messages) == 1
+
+    # the email was sent to Microsoft with the correct subject line
+    message = mailer.messages[0]
+    assert message["To"] == app.config["MICROSOFT_TASK_ORDER_EMAIL_ADDRESS"]
+    assert message["Subject"] == translate(
+        "email.task_order_sent.subject", {"to_number": to_number}
+    )
+
+    # the email was sent as a multipart message with two parts -- the message
+    # body and the attachment
+    assert message.is_multipart()
+    message_payload = message.get_payload()
+    assert len(message_payload) == 2
+
+    # A body and attachment were in the email
+    body = next(
+        (
+            part
+            for part in message_payload
+            if part["Content-Type"] == 'text/plain; charset="utf-8"'
+        ),
+        None,
+    )
+    attachment = next(
+        (part for part in message_payload if part["Content-Type"] == "application/pdf"),
+        None,
+    )
+    assert body
+    assert attachment
+
+    assert (
+        attachment["Content-Disposition"]
+        == f"attachment; filename=\"{downloaded_task_order['name']}\""
+    )
diff --git a/translations.yaml b/translations.yaml
index 4fdb3b3c..44dd2a92 100644
--- a/translations.yaml
+++ b/translations.yaml
@@ -84,6 +84,9 @@ email:
   application_invite: "{inviter_name} has invited you to a JEDI cloud application"
   portfolio_invite: "{inviter_name} has invited you to a JEDI cloud portfolio"
   environment_ready: JEDI cloud environment ready
+  task_order_sent:
+    subject: "Task Order {to_number}"
+    body: "Task Order number {to_number} updated."
 empty_state:
   applications:
     header:
@@ -480,7 +483,6 @@ portfolios:
         "False": View Team
         "True": Edit Team
       perms_env_mgmt:
-
         "False": View Environments
         "True": Edit Environments
       roles: