diff --git a/mongoose.c b/mongoose.c
index 3be4fd44..05b7406b 100644
--- a/mongoose.c
+++ b/mongoose.c
@@ -5812,9 +5812,10 @@ static void mg_ws_cb(struct mg_connection *c, int ev, void *ev_data,
           if (final) mg_call(c, MG_EV_WS_MSG, &m);
           break;
         case WEBSOCKET_OP_CLOSE:
-          MG_DEBUG(("%lu Got WS CLOSE", c->id));
+          MG_DEBUG(("%lu WS CLOSE", c->id));
           mg_call(c, MG_EV_WS_CTL, &m);
-          mg_ws_send(c, "", 0, WEBSOCKET_OP_CLOSE);
+          // Echo the payload of the received CLOSE message back to the sender
+          mg_ws_send(c, m.data.ptr, m.data.len, WEBSOCKET_OP_CLOSE);
           c->is_draining = 1;
           break;
         default:
diff --git a/src/ws.c b/src/ws.c
index eace26ef..f836cc7f 100644
--- a/src/ws.c
+++ b/src/ws.c
@@ -192,9 +192,10 @@ static void mg_ws_cb(struct mg_connection *c, int ev, void *ev_data,
           if (final) mg_call(c, MG_EV_WS_MSG, &m);
           break;
         case WEBSOCKET_OP_CLOSE:
-          MG_DEBUG(("%lu Got WS CLOSE", c->id));
+          MG_DEBUG(("%lu WS CLOSE", c->id));
           mg_call(c, MG_EV_WS_CTL, &m);
-          mg_ws_send(c, "", 0, WEBSOCKET_OP_CLOSE);
+          // Echo the payload of the received CLOSE message back to the sender
+          mg_ws_send(c, m.data.ptr, m.data.len, WEBSOCKET_OP_CLOSE);
           c->is_draining = 1;
           break;
         default: