diff --git a/include/bluetooth/bluetooth.h b/include/bluetooth/bluetooth.h
index ab8fe320f0c..8f4f96d19c7 100644
--- a/include/bluetooth/bluetooth.h
+++ b/include/bluetooth/bluetooth.h
@@ -363,11 +363,14 @@ struct bt_le_adv_param {
  *  @param sd_len Number of elements in sd
  *
  *  @return Zero on success or (negative) error code otherwise.
+ *  @return -ENOMEM No free connection objects available for connectable
+ *                  advertiser.
  *  @return -ECONNREFUSED When connectable advertising is requested and there
- *			  is already maximum number of connections established.
- *			  This error code is only guaranteed when using Zephyr
- *			  controller, for other controllers code returned in
- *			  this case may be -EIO.
+ *                        is already maximum number of connections established
+ *                        in the controller.
+ *                        This error code is only guaranteed when using Zephyr
+ *                        controller, for other controllers code returned in
+ *                        this case may be -EIO.
  */
 int bt_le_adv_start(const struct bt_le_adv_param *param,
 		    const struct bt_data *ad, size_t ad_len,
diff --git a/include/bluetooth/conn.h b/include/bluetooth/conn.h
index 11dc05948f8..ad81a19ee9a 100644
--- a/include/bluetooth/conn.h
+++ b/include/bluetooth/conn.h
@@ -304,6 +304,7 @@ struct bt_conn *bt_conn_create_le(const bt_addr_le_t *peer,
  *  @param param Initial connection parameters.
  *
  *  @return Zero on success or (negative) error code on failure.
+ *  @return -ENOMEM No free connection object available.
  */
 int bt_conn_create_auto_le(const struct bt_le_conn_param *param);
 
@@ -492,6 +493,15 @@ struct bt_conn_cb {
 	 *  This callback notifies the application that a connection
 	 *  has been disconnected.
 	 *
+	 *  When this callback is called the stack still has one reference to
+	 *  the connection object. If the application in this callback tries to
+	 *  start either a connectable advertiser or create a new connection
+	 *  this might fail because there are no free connection objects
+	 *  available.
+	 *  To avoid this issue it is recommended to either start connectable
+	 *  advertise or create a new connection using @ref k_work_submit or
+	 *  increase :option:`CONFIG_BT_MAX_CONN`.
+	 *
 	 *  @param conn Connection object.
 	 *  @param reason HCI reason for the disconnection.
 	 */