diff --git a/compiler/ballerina-lang/src/main/java/org/wso2/ballerinalang/compiler/semantics/analyzer/Types.java b/compiler/ballerina-lang/src/main/java/org/wso2/ballerinalang/compiler/semantics/analyzer/Types.java
index e21f15a19e54..0e71020f9c7f 100644
--- a/compiler/ballerina-lang/src/main/java/org/wso2/ballerinalang/compiler/semantics/analyzer/Types.java
+++ b/compiler/ballerina-lang/src/main/java/org/wso2/ballerinalang/compiler/semantics/analyzer/Types.java
@@ -1498,6 +1498,7 @@ public boolean isInherentlyImmutableType(BType type) {
             case TypeTags.INVOKABLE:
             case TypeTags.TYPEDESC:
             case TypeTags.HANDLE:
+            case TypeTags.REGEXP:    
                 return true;
             case TypeTags.XML:
                 return getImpliedType(((BXMLType) type).constraint).tag == TypeTags.NEVER;