diff --git a/schema/Entity.json b/schema/Entity.json
index 24782155d0cd373895d1fc9581ae33408b97c009..a1eee1da5d18dbcdefa88ec3ead61cb95e3c0c91 100644
--- a/schema/Entity.json
+++ b/schema/Entity.json
@@ -19,13 +19,26 @@
         },
         "value": {
           "oneOf": [
-            "string",
-            "number",
-            "boolean",
-            "array",
-            "object"
+            {
+              "type": "string"
+            },
+            {
+              "type": "number"
+            },
+            {
+              "type": "boolean"
+            },
+            {
+              "type": "array"
+            },
+            {
+              "type": "object"
+            }
           ]
         },
+        "unitCode": {
+          "$ref": "https://forge.etsi.org/rep/NGSI-LD/NGSI-LD/raw/master/schema/common.json#/definitions/unitCode"
+        },
         "observedAt": {
           "$ref": "https://forge.etsi.org/rep/NGSI-LD/NGSI-LD/raw/master/schema/common.json#/definitions/observedAt"
         },
diff --git a/schema/common.json b/schema/common.json
index a3214d7e251fa808a56d44f4c1e59e9ea0c3ed9d..c4487f95647da360730fab5456341db4668ea4ca 100644
--- a/schema/common.json
+++ b/schema/common.json
@@ -12,6 +12,9 @@
       "type": "string",
       "pattern": "^((\\d|[a-zA-Z]|_)+(:(\\d|[a-zA-Z]|_)+)?(#\\d+)?)$|^(@context)$"
     },
+    "unitCode": {
+      "type": "string"
+    },
     "observedAt": {
       "type": "string",
       "format": "date-time"