diff --git a/src/variables/time_mon.cc b/src/variables/time_mon.cc
index 18059112..cbc73bd4 100644
--- a/src/variables/time_mon.cc
+++ b/src/variables/time_mon.cc
@@ -46,7 +46,7 @@ void TimeMon::evaluate(Transaction *transaction,
     struct tm timeinfo;
     localtime_r(&timer, &timeinfo);
 
-    transaction->m_variableTimeMin.assign(std::to_string(timeinfo.tm_mon));
+    transaction->m_variableTimeMin.assign(std::to_string(timeinfo.tm_mon + 1));
 
     l->push_back(new VariableValue(&m_retName,
         &transaction->m_variableTimeMin));
diff --git a/test/test-cases/regression/variable-TIME_MON.json b/test/test-cases/regression/variable-TIME_MON.json
index 663956ae..b7011214 100644
--- a/test/test-cases/regression/variable-TIME_MON.json
+++ b/test/test-cases/regression/variable-TIME_MON.json
@@ -33,7 +33,8 @@
       ]
     },
     "expected":{
-      "debug_log":"Target value: \"([0-9]+)\" \\(Variable: TIME_MON\\)"
+      "http_code": 200,
+      "debug_log":"Target value: \"[1-9][012]?\" \\(Variable: TIME_MON\\)"
     },
     "rules":[
       "SecRuleEngine On",