diff --git a/modules/programs/aerc-accounts.nix b/modules/programs/aerc-accounts.nix
index a40877f5..5c772c2c 100644
--- a/modules/programs/aerc-accounts.nix
+++ b/modules/programs/aerc-accounts.nix
@@ -177,21 +177,20 @@ in {
               params = cfg.aerc.smtpOauth2Params;
             };
 
-            protocol = if smtp.tls.enable && !smtp.tls.useStartTls then
-              "smtps${loginMethod'}"
+            protocol = if smtp.tls.enable then
+              if smtp.tls.useStartTls then
+                "smtp${loginMethod'}"
+              else
+                "smtps${loginMethod'}"
             else
-              "smtp${loginMethod'}";
+              "smtp+insecure${loginMethod'}";
 
             port' = optPort smtp.port;
 
-            smtp-starttls =
-              if smtp.tls.enable && smtp.tls.useStartTls then "yes" else null;
-
           in {
             outgoing =
               "${protocol}://${userName}@${smtp.host}${port'}${oauthParams'}";
-          } // optPwCmd "outgoing" passwordCommand
-          // optAttr "smtp-starttls" smtp-starttls;
+          } // optPwCmd "outgoing" passwordCommand;
 
         msmtp = cfg: {
           outgoing = "msmtpq --read-envelope-from --read-recipients";
diff --git a/tests/modules/programs/aerc/extraAccounts.expected b/tests/modules/programs/aerc/extraAccounts.expected
index a53e6e00..172e3452 100644
--- a/tests/modules/programs/aerc/extraAccounts.expected
+++ b/tests/modules/programs/aerc/extraAccounts.expected
@@ -38,7 +38,6 @@ source-cred-cmd = echo PaSsWorD!
 [e_smtp-nopasscmd-tls-starttls]
 from = Foo Bar <addr@mail.invalid>
 outgoing = smtp+plain://foobar@smtp.host.invalid:42
-smtp-starttls = yes
 
 [f_smtp-passcmd-tls-nostarttls]
 from = Foo Bar <addr@mail.invalid>
@@ -47,12 +46,12 @@ outgoing-cred-cmd = echo PaSsWorD!
 
 [g_smtp-passcmd-notls-nostarttls]
 from = Foo Bar <addr@mail.invalid>
-outgoing = smtp+plain://foobar@smtp.host.invalid:42
+outgoing = smtp+insecure+plain://foobar@smtp.host.invalid:42
 outgoing-cred-cmd = echo PaSsWorD!
 
 [h_smtp-passcmd-notls-starttls]
 from = Foo Bar <addr@mail.invalid>
-outgoing = smtp+plain://foobar@smtp.host.invalid:42
+outgoing = smtp+insecure+plain://foobar@smtp.host.invalid:42
 outgoing-cred-cmd = echo PaSsWorD!
 
 [i_maildir-mbsync]