diff --git a/homeassistant/components/modbus/services.yaml b/homeassistant/components/modbus/services.yaml
index 835927e4627..87e8b98fa21 100644
--- a/homeassistant/components/modbus/services.yaml
+++ b/homeassistant/components/modbus/services.yaml
@@ -8,8 +8,8 @@ write_coil:
       required: true
       selector:
         number:
-          min: 1
-          max: 255
+          min: 0
+          max: 65535
     state:
       name: State
       description: State to write.
@@ -42,8 +42,8 @@ write_register:
       required: true
       selector:
         number:
-          min: 1
-          max: 255
+          min: 0
+          max: 65535
     unit:
       name: Unit
       description: Address of the modbus unit.