diff --git a/doc/configuration.txt b/doc/configuration.txt
index 8c6e6158d..632268f94 100644
--- a/doc/configuration.txt
+++ b/doc/configuration.txt
@@ -9089,11 +9089,14 @@ no option abortonclose
       pending in the queue or when trying to connect). If the request is
       already being served by a server, then the connection to the server is
       in turn switched to half-close to indicate the same condition to the
-      server, which will then decide how to proceed.
+      server, which will then decide how to proceed. This is the default for
+      HTTP-mode backends.
 
   The recommendation is to enable this option on internet-facing TLS endpoints
   and HTTP services, and to disable it for pure TCP ones as well as unexposed
-  legacy environments.
+  legacy environments. It is enabled by default in HTTP backends, and may be
+  forcefully disabled by prepending the "no" keyword before it, either in the
+  backend section itself, or in the "defaults" section it inherits from.
 
   If this option has been enabled in a "defaults" section, it can be disabled
   in a specific instance by prepending the "no" keyword before it.
diff --git a/include/haproxy/proxy.h b/include/haproxy/proxy.h
index 46f5df84b..7be5a55d5 100644
--- a/include/haproxy/proxy.h
+++ b/include/haproxy/proxy.h
@@ -141,10 +141,18 @@ static inline void proxy_reset_timeouts(struct proxy *proxy)
 	proxy->timeout.tunnel = TICK_ETERNITY;
 }
 
-/* return proxy's abortonclose status: 0=off, non-zero=on */
+/* return proxy's abortonclose status: 0=off, non-zero=on.
+ * Considers the proxy's mode when neither on/off was set,
+ * and HTTP mode defaults to on.
+ */
 static inline int proxy_abrt_close(const struct proxy *px)
 {
-	return !!(px->options & PR_O_ABRT_CLOSE);
+	if (px->options & PR_O_ABRT_CLOSE)
+		return 1;
+	else if (px->no_options & PR_O_ABRT_CLOSE)
+		return 0;
+	/* When unset: 1 for HTTP, 0 for TCP */
+	return px->mode == PR_MODE_HTTP;
 }
 
 /* increase the number of cumulated connections received on the designated frontend */
diff --git a/reg-tests/http-messaging/http_abortonclose.vtc b/reg-tests/http-messaging/http_abortonclose.vtc
index f9ad90621..33b194dff 100644
--- a/reg-tests/http-messaging/http_abortonclose.vtc
+++ b/reg-tests/http-messaging/http_abortonclose.vtc
@@ -126,6 +126,7 @@ haproxy h2 -conf {
 
     defaults
         mode http
+        no option abortonclose
         retries 1
         timeout client  10s
         timeout server  10s