diff --git a/esphome/components/modbus/__init__.py b/esphome/components/modbus/__init__.py
index 88105b7baf..cada835905 100644
--- a/esphome/components/modbus/__init__.py
+++ b/esphome/components/modbus/__init__.py
@@ -41,3 +41,4 @@ def register_modbus_device(var, config):
     parent = yield cg.get_variable(config[CONF_MODBUS_ID])
     cg.add(var.set_parent(parent))
     cg.add(var.set_address(config[CONF_ADDRESS]))
+    cg.add(parent.register_device(var))