diff --git a/src/applications/config/option/PhabricatorPHPMailerConfigOptions.php b/src/applications/config/option/PhabricatorPHPMailerConfigOptions.php
index d4918f934c..a9b5643206 100644
--- a/src/applications/config/option/PhabricatorPHPMailerConfigOptions.php
+++ b/src/applications/config/option/PhabricatorPHPMailerConfigOptions.php
@@ -44,6 +44,23 @@ final class PhabricatorPHPMailerConfigOptions
       $this->newOption('phpmailer.smtp-password', 'string', null)
         ->setMasked(true)
         ->setDescription(pht('Password for SMTP.')),
+      $this->newOption('phpmailer.smtp-encoding', 'string', '8bit')
+        ->setSummary(pht('Configure how mail is encoded.'))
+        ->setDescription(
+          pht(
+            "Mail is normally encoded in `8bit`, which works correctly with ".
+            "most MTAs. However, some MTAs do not work well with this ".
+            "encoding. If you're having trouble with mail being mangled or ".
+            "arriving with too many or too few newlines, you may try ".
+            "adjusting this setting.\n\n".
+            "Supported values are `8bit` (default), `quoted-printable`, ".
+            "`7bit`, `binary` and `base64`.\n\n".
+            "The settings in the table below may work well.\n\n".
+            "| MTA | Setting | Notes\n".
+            "|-----|---------|------\n".
+            "| SendGrid via SMTP | `quoted-printable` | Double newlines under ".
+            "`8bit`.\n".
+            "| All Other MTAs | `8bit` | Default setting.")),
     );
   }
 
diff --git a/src/applications/metamta/adapter/PhabricatorMailImplementationPHPMailerAdapter.php b/src/applications/metamta/adapter/PhabricatorMailImplementationPHPMailerAdapter.php
index 32f152f8ff..d9609b1a7b 100644
--- a/src/applications/metamta/adapter/PhabricatorMailImplementationPHPMailerAdapter.php
+++ b/src/applications/metamta/adapter/PhabricatorMailImplementationPHPMailerAdapter.php
@@ -13,10 +13,8 @@ final class PhabricatorMailImplementationPHPMailerAdapter
     $this->mailer = new PHPMailer($use_exceptions = true);
     $this->mailer->CharSet = 'utf-8';
 
-    // NOTE: This works around what seems to be a bug in SendGrid, see
-    // D10278. This affects other SMTP mailers too, but as long as they
-    // don't have an opposite bug to SendGrid's bug that should be OK.
-    $this->mailer->Encoding = 'quoted-printable';
+    $encoding = PhabricatorEnv::getEnvConfig('phpmailer.smtp-encoding', '8bit');
+    $this->mailer->Encoding = $encoding;
 
     // By default, PHPMailer sends one mail per recipient. We handle
     // multiplexing higher in the stack, so tell it to send mail exactly
diff --git a/src/applications/metamta/adapter/PhabricatorMailImplementationPHPMailerLiteAdapter.php b/src/applications/metamta/adapter/PhabricatorMailImplementationPHPMailerLiteAdapter.php
index 5b27b78561..e758832039 100644
--- a/src/applications/metamta/adapter/PhabricatorMailImplementationPHPMailerLiteAdapter.php
+++ b/src/applications/metamta/adapter/PhabricatorMailImplementationPHPMailerLiteAdapter.php
@@ -15,7 +15,9 @@ class PhabricatorMailImplementationPHPMailerLiteAdapter
     require_once $root.'/externals/phpmailer/class.phpmailer-lite.php';
     $this->mailer = new PHPMailerLite($use_exceptions = true);
     $this->mailer->CharSet = 'utf-8';
-    $this->mailer->Encoding = 'quoted-printable';
+
+    $encoding = PhabricatorEnv::getEnvConfig('phpmailer.smtp-encoding', '8bit');
+    $this->mailer->Encoding = $encoding;
 
     // By default, PHPMailerLite sends one mail per recipient. We handle
     // multiplexing higher in the stack, so tell it to send mail exactly
diff --git a/src/docs/user/configuration/configuring_outbound_email.diviner b/src/docs/user/configuration/configuring_outbound_email.diviner
index fdc5abf153..77d09f7cf2 100644
--- a/src/docs/user/configuration/configuring_outbound_email.diviner
+++ b/src/docs/user/configuration/configuring_outbound_email.diviner
@@ -12,7 +12,7 @@ Phabricator can send outbound email via several different providers, called
 |---------|-------|------|---------|-------|
 | Mailgun | Easy | Cheap | Yes | Recommended |
 | Amazon SES | Easy | Cheap | No | Recommended |
-| SendGrid | Easy | Cheap | Yes | |
+| SendGrid | Medium | Cheap | Yes | Discouraged (See Note) |
 | External SMTP | Medium | Varies | No | Gmail, etc. |
 | Local SMTP | Hard | Free | No | (Default) sendmail, postfix, etc |
 | Custom | Hard | Free | No | Write an adapter for some other service. |
@@ -34,6 +34,11 @@ it to be able to deliver mail. You should receive setup warnings if they are
 not. For more information on using daemons, see
 @{article:Managing Daemons with phd}.
 
+**Note on SendGrid**: Users have experienced a number of odd issues with
+SendGrid, compared to fewer issues with other mailers. We discourage SendGrid
+unless you're already using it. If you send to SendGrid via SMTP, you may need
+to adjust `phpmailer.smtp-encoding`.
+
 = Basics =
 
 Regardless of how outbound email is delivered, you should configure these keys
@@ -83,6 +88,9 @@ document. If you can already send outbound email from the command line or know
 how to configure it, this option is straightforward. If you have no idea how to
 do any of this, strongly consider using Mailgun or Amazon SES instead.
 
+If you experience issues with mail getting mangled (for example, arriving with
+too many or too few newlines) you may try adjusting `phpmailer.smtp-encoding`.
+
 = Adapter: SMTP =
 
 You can use this adapter to send mail via an external SMTP server, like Gmail.
@@ -97,6 +105,9 @@ To do this, set these configuration keys:
   - **phpmailer.smtp-password**: set to your password used for authentication.
   - **phpmailer.smtp-protocol**: set to `tls` or `ssl` if necessary. Use
     `ssl` for Gmail.
+  - **phpmailer.smtp-encoding**: Normally safe to leave as the default, but
+    adjusting it may help resolve mail mangling issues (for example, mail
+    arriving with too many or too few newlines).
 
 = Adapter: Mailgun =