diff --git a/config.c b/config.c
index bdffd6bb..26d57acc 100644
--- a/config.c
+++ b/config.c
@@ -1628,6 +1628,9 @@ void setup_config_box(struct controlbox *b, int midsession,
     ctrl_checkbox(s, "Flush log file frequently", 'u',
 		 HELPCTX(logging_flush),
 		 conf_checkbox_handler, I(CONF_logflush));
+    ctrl_checkbox(s, "Include header", 'h',
+		 HELPCTX(logging_header),
+		 conf_checkbox_handler, I(CONF_logheader));
 
     if ((midsession && protocol == PROT_SSH) ||
         (!midsession && backend_vt_from_proto(PROT_SSH))) {
diff --git a/doc/config.but b/doc/config.but
index c76e1847..96323ce6 100644
--- a/doc/config.but
+++ b/doc/config.but
@@ -246,6 +246,15 @@ warned that the log file may not always be up to date as a result
 (although it will of course be flushed when it is closed, for instance
 at the end of a session).
 
+\S{config-logheader} \I{log file, header}\q{Include header}
+
+\cfg{winhelp-topic}{logging.header}
+
+This option allows you to choose whether to include a header line
+with the date and time when the log file is opened. It may be useful to
+disable this if the log file is being used as realtime input to other
+programs that don't expect the header line.
+
 \S{config-logssh} Options specific to \i{SSH packet log}ging
 
 These options only apply if SSH packet data is being logged.
diff --git a/logging.c b/logging.c
index 0393b7bf..da502c86 100644
--- a/logging.c
+++ b/logging.c
@@ -103,7 +103,7 @@ static void logfopen_callback(void *vctx, int mode)
         }
     }
 
-    if (ctx->state == L_OPEN) {
+    if (ctx->state == L_OPEN && conf_get_int(ctx->conf, CONF_logheader)) {
 	/* Write header line into log file. */
 	tm = ltime();
 	strftime(buf, 24, "%Y.%m.%d %H:%M:%S", &tm);
diff --git a/putty.h b/putty.h
index 3963e48e..1a0d1ca2 100644
--- a/putty.h
+++ b/putty.h
@@ -931,6 +931,7 @@ void cleanup_exit(int);
     X(INT, NONE, logtype) \
     X(INT, NONE, logxfovr) \
     X(INT, NONE, logflush) \
+    X(INT, NONE, logheader) \
     X(INT, NONE, logomitpass) \
     X(INT, NONE, logomitdata) \
     X(INT, NONE, hide_mouseptr) \
diff --git a/settings.c b/settings.c
index ab735488..5b613b66 100644
--- a/settings.c
+++ b/settings.c
@@ -524,6 +524,7 @@ void save_open_settings(settings_w *sesskey, Conf *conf)
     write_setting_i(sesskey, "LogType", conf_get_int(conf, CONF_logtype));
     write_setting_i(sesskey, "LogFileClash", conf_get_int(conf, CONF_logxfovr));
     write_setting_i(sesskey, "LogFlush", conf_get_int(conf, CONF_logflush));
+    write_setting_i(sesskey, "LogHeader", conf_get_int(conf, CONF_logheader));
     write_setting_i(sesskey, "SSHLogOmitPasswords", conf_get_int(conf, CONF_logomitpass));
     write_setting_i(sesskey, "SSHLogOmitData", conf_get_int(conf, CONF_logomitdata));
     p = "raw";
@@ -785,6 +786,7 @@ void load_open_settings(settings_r *sesskey, Conf *conf)
     gppi(sesskey, "LogType", 0, conf, CONF_logtype);
     gppi(sesskey, "LogFileClash", LGXF_ASK, conf, CONF_logxfovr);
     gppi(sesskey, "LogFlush", 1, conf, CONF_logflush);
+    gppi(sesskey, "LogHeader", 1, conf, CONF_logheader);
     gppi(sesskey, "SSHLogOmitPasswords", 1, conf, CONF_logomitpass);
     gppi(sesskey, "SSHLogOmitData", 0, conf, CONF_logomitdata);
 
diff --git a/windows/winhelp.h b/windows/winhelp.h
index c9be5f44..2ecb537a 100644
--- a/windows/winhelp.h
+++ b/windows/winhelp.h
@@ -23,6 +23,7 @@
 #define WINHELP_CTX_logging_filename "logging.filename:config-logfilename"
 #define WINHELP_CTX_logging_exists "logging.exists:config-logfileexists"
 #define WINHELP_CTX_logging_flush "logging.flush:config-logflush"
+#define WINHELP_CTX_logging_header "logging.header:config-logheader"
 #define WINHELP_CTX_logging_ssh_omit_password "logging.ssh.omitpassword:config-logssh"
 #define WINHELP_CTX_logging_ssh_omit_data "logging.ssh.omitdata:config-logssh"
 #define WINHELP_CTX_keyboard_backspace "keyboard.backspace:config-backspace"