diff --git a/doc/guix.texi b/doc/guix.texi
index 95e9ebb35bb..64ef5964745 100644
--- a/doc/guix.texi
+++ b/doc/guix.texi
@@ -29879,6 +29879,7 @@ remote servers.  Run @command{man smtpd.conf} for more information.
 @item @code{log-file} (default: @code{"/var/log/mail.log"})
 The file location for the OpenSMTPD log file.  Logging occurs in the
 foreground via the Shepherd, i.e. OpenSMTPD does not detach.
+When set to @code{#f} OpenSMTPD will instead detach and log to the syslog.
 
 @item @code{setgid-commands?} (default: @code{#t})
 Make the following commands setgid to @code{smtpq} so they can be
diff --git a/gnu/services/mail.scm b/gnu/services/mail.scm
index eef46d8f63d..edcc0caa97c 100644
--- a/gnu/services/mail.scm
+++ b/gnu/services/mail.scm
@@ -1744,8 +1744,11 @@ match from local for any action outbound
            (documentation "Run the OpenSMTPD daemon.")
            (start (let ((smtpd (file-append package "/sbin/smtpd")))
                     #~(make-forkexec-constructor
-                       (list #$smtpd "-d" "-f" #$config-file)
-                       #:log-file #$log-file)))
+                       (list #$smtpd "-f" #$config-file
+                             #$@(if log-file '("-d") '()))
+                       #$@(if log-file
+                              (list #:log-file log-file)
+                              (list #:pid-file "/var/run/smtpd.pid")))))
            (stop #~(make-kill-destructor))))))
 
 (define %opensmtpd-accounts