diff --git a/features/FEATURE_BLE/targets/TARGET_NORDIC/TARGET_NRF51/source/nRF5xn.h b/features/FEATURE_BLE/targets/TARGET_NORDIC/TARGET_NRF51/source/nRF5xn.h
index 18b76b405c..25d6c21656 100644
--- a/features/FEATURE_BLE/targets/TARGET_NORDIC/TARGET_NRF51/source/nRF5xn.h
+++ b/features/FEATURE_BLE/targets/TARGET_NORDIC/TARGET_NRF51/source/nRF5xn.h
@@ -134,7 +134,7 @@ public:
     virtual void processEvents();
 
 public:
-    static nRF5xn& Instance(BLE::InstanceID_t instanceId);
+    static nRF5xn& Instance(BLE::InstanceID_t instanceId = BLE::DEFAULT_INSTANCE);
 
 private:
     bool              initialized;
diff --git a/features/FEATURE_BLE/targets/TARGET_NORDIC/TARGET_NRF52/source/nRF5xn.h b/features/FEATURE_BLE/targets/TARGET_NORDIC/TARGET_NRF52/source/nRF5xn.h
index 7d6c4c3522..6efd3ec37a 100644
--- a/features/FEATURE_BLE/targets/TARGET_NORDIC/TARGET_NRF52/source/nRF5xn.h
+++ b/features/FEATURE_BLE/targets/TARGET_NORDIC/TARGET_NRF52/source/nRF5xn.h
@@ -133,7 +133,7 @@ public:
     virtual void processEvents();
 
 public:
-    static nRF5xn& Instance(BLE::InstanceID_t instanceId);
+    static nRF5xn& Instance(BLE::InstanceID_t instanceId = BLE::DEFAULT_INSTANCE);
 
 private:
     bool              initialized;