diff --git a/CTFd/config.py b/CTFd/config.py
index 7ac2ef5e..6616c25f 100644
--- a/CTFd/config.py
+++ b/CTFd/config.py
@@ -143,10 +143,12 @@ class Config(object):
         Whether to connect to the SMTP server over SSL
 
     MAILGUN_API_KEY
-        Mailgun API key to send email over Mailgun
+        Mailgun API key to send email over Mailgun. As of CTFd v3, Mailgun integration is deprecated.
+        Installations using the Mailgun API should migrate over to SMTP settings.
 
     MAILGUN_BASE_URL
-        Mailgun base url to send email over Mailgun
+        Mailgun base url to send email over Mailgun. As of CTFd v3, Mailgun integration is deprecated.
+        Installations using the Mailgun API should migrate over to SMTP settings.
     """
     MAILFROM_ADDR = os.getenv("MAILFROM_ADDR") or "noreply@ctfd.io"
     MAIL_SERVER = os.getenv("MAIL_SERVER") or None
diff --git a/CTFd/themes/admin/templates/configs/email.html b/CTFd/themes/admin/templates/configs/email.html
index 384e91f3..b2c403ca 100644
--- a/CTFd/themes/admin/templates/configs/email.html
+++ b/CTFd/themes/admin/templates/configs/email.html
@@ -232,6 +232,9 @@
 				</div>
 			</div>
 			<div role="tabpanel" class="tab-pane" id="mailgun">
+				<div class="alert alert-warning" role="alert">
+					Mailgun integration is deprecated! Please see your Mailgun account for SMTP credentials.
+				</div>
 				<div class="form-group">
 					<label>
 						Mailgun API Base URL<br>
diff --git a/docs/configuration.rst b/docs/configuration.rst
index 9f1b926e..2cf54caf 100644
--- a/docs/configuration.rst
+++ b/docs/configuration.rst
@@ -69,11 +69,11 @@ Whether to connect to the SMTP server over SSL
 
 MAILGUN_API_KEY
 ~~~~~~~~~~~~~~~
-Mailgun API key to send email over Mailgun
+Mailgun API key to send email over Mailgun. As of CTFd v3, Mailgun integration is deprecated. Installations using the Mailgun API should migrate over to SMTP settings.
 
 MAILGUN_BASE_URL
 ~~~~~~~~~~~~~~~~
-Mailgun base url to send email over Mailgun
+Mailgun base url to send email over Mailgun. As of CTFd v3, Mailgun integration is deprecated. Installations using the Mailgun API should migrate over to SMTP settings.
 
 LOG_FOLDER
 ~~~~~~~~~~