diff --git a/tests/baselines/reference/unionTypeIdentity.errors.txt b/tests/baselines/reference/unionTypeIdentity.errors.txt
new file mode 100644
index 0000000000..77d25bd78d
--- /dev/null
+++ b/tests/baselines/reference/unionTypeIdentity.errors.txt
@@ -0,0 +1,20 @@
+tests/cases/conformance/types/typeRelationships/typeAndMemberIdentity/unionTypeIdentity.ts(6,5): error TS2403: Subsequent variable declarations must have the same type.  Variable 'strOrNum' must be of type 'string | boolean', but here has type 'string'.
+tests/cases/conformance/types/typeRelationships/typeAndMemberIdentity/unionTypeIdentity.ts(7,5): error TS2403: Subsequent variable declarations must have the same type.  Variable 'strOrNum' must be of type 'string | boolean', but here has type 'boolean'.
+tests/cases/conformance/types/typeRelationships/typeAndMemberIdentity/unionTypeIdentity.ts(8,5): error TS2403: Subsequent variable declarations must have the same type.  Variable 'strOrNum' must be of type 'string | boolean', but here has type 'number'.
+
+
+==== tests/cases/conformance/types/typeRelationships/typeAndMemberIdentity/unionTypeIdentity.ts (3 errors) ====
+    // Two types are considered identical when
+    // they are union types with identical sets of constituent types, or
+    var strOrNum: string | boolean;
+    var strOrNum: boolean | string;
+    var strOrNum: boolean | string | boolean;
+    var strOrNum: string; // error
+        ~~~~~~~~
+!!! error TS2403: Subsequent variable declarations must have the same type.  Variable 'strOrNum' must be of type 'string | boolean', but here has type 'string'.
+    var strOrNum: boolean; // error
+        ~~~~~~~~
+!!! error TS2403: Subsequent variable declarations must have the same type.  Variable 'strOrNum' must be of type 'string | boolean', but here has type 'boolean'.
+    var strOrNum: number; // error
+        ~~~~~~~~
+!!! error TS2403: Subsequent variable declarations must have the same type.  Variable 'strOrNum' must be of type 'string | boolean', but here has type 'number'.
\ No newline at end of file
diff --git a/tests/baselines/reference/unionTypeIdentity.js b/tests/baselines/reference/unionTypeIdentity.js
new file mode 100644
index 0000000000..82cad82797
--- /dev/null
+++ b/tests/baselines/reference/unionTypeIdentity.js
@@ -0,0 +1,19 @@
+//// [unionTypeIdentity.ts]
+// Two types are considered identical when
+// they are union types with identical sets of constituent types, or
+var strOrNum: string | boolean;
+var strOrNum: boolean | string;
+var strOrNum: boolean | string | boolean;
+var strOrNum: string; // error
+var strOrNum: boolean; // error
+var strOrNum: number; // error
+
+//// [unionTypeIdentity.js]
+// Two types are considered identical when
+// they are union types with identical sets of constituent types, or
+var strOrNum;
+var strOrNum;
+var strOrNum;
+var strOrNum; // error
+var strOrNum; // error
+var strOrNum; // error
diff --git a/tests/cases/conformance/types/typeRelationships/typeAndMemberIdentity/unionTypeIdentity.ts b/tests/cases/conformance/types/typeRelationships/typeAndMemberIdentity/unionTypeIdentity.ts
new file mode 100644
index 0000000000..79100f476b
--- /dev/null
+++ b/tests/cases/conformance/types/typeRelationships/typeAndMemberIdentity/unionTypeIdentity.ts
@@ -0,0 +1,8 @@
+// Two types are considered identical when
+// they are union types with identical sets of constituent types, or
+var strOrNum: string | boolean;
+var strOrNum: boolean | string;
+var strOrNum: boolean | string | boolean;
+var strOrNum: string; // error
+var strOrNum: boolean; // error
+var strOrNum: number; // error
\ No newline at end of file