diff --git a/tests/baselines/reference/unionTypeCallSignatures3.js b/tests/baselines/reference/unionTypeCallSignatures3.js
new file mode 100644
index 00000000000..2dae152e474
--- /dev/null
+++ b/tests/baselines/reference/unionTypeCallSignatures3.js
@@ -0,0 +1,39 @@
+//// [unionTypeCallSignatures3.ts]
+function f1(s: string) { }
+function f2(s?: string) { }
+function f3(...s: string[]) { }
+function f4(s: string, s2?: string) { }
+function f5(s?: string, n?: number) { }
+function f6(s?: string, ...n: number[]) { }
+function f7(s: string, ...sRest: string[]) { }
+
+var fUnion: typeof f1 | typeof f2 | typeof f3 | typeof f4 | typeof f5 | typeof f6 | typeof f7;
+
+fUnion(""); // All constituents can be called by passing a single string.
+
+
+//// [unionTypeCallSignatures3.js]
+function f1(s) { }
+function f2(s) { }
+function f3() {
+    var s = [];
+    for (var _i = 0; _i < arguments.length; _i++) {
+        s[_i - 0] = arguments[_i];
+    }
+}
+function f4(s, s2) { }
+function f5(s, n) { }
+function f6(s) {
+    var n = [];
+    for (var _i = 1; _i < arguments.length; _i++) {
+        n[_i - 1] = arguments[_i];
+    }
+}
+function f7(s) {
+    var sRest = [];
+    for (var _i = 1; _i < arguments.length; _i++) {
+        sRest[_i - 1] = arguments[_i];
+    }
+}
+var fUnion;
+fUnion(""); // All constituents can be called by passing a single string.
diff --git a/tests/baselines/reference/unionTypeCallSignatures3.symbols b/tests/baselines/reference/unionTypeCallSignatures3.symbols
new file mode 100644
index 00000000000..45dffe2d821
--- /dev/null
+++ b/tests/baselines/reference/unionTypeCallSignatures3.symbols
@@ -0,0 +1,46 @@
+=== tests/cases/conformance/types/union/unionTypeCallSignatures3.ts ===
+function f1(s: string) { }
+>f1 : Symbol(f1, Decl(unionTypeCallSignatures3.ts, 0, 0))
+>s : Symbol(s, Decl(unionTypeCallSignatures3.ts, 0, 12))
+
+function f2(s?: string) { }
+>f2 : Symbol(f2, Decl(unionTypeCallSignatures3.ts, 0, 26))
+>s : Symbol(s, Decl(unionTypeCallSignatures3.ts, 1, 12))
+
+function f3(...s: string[]) { }
+>f3 : Symbol(f3, Decl(unionTypeCallSignatures3.ts, 1, 27))
+>s : Symbol(s, Decl(unionTypeCallSignatures3.ts, 2, 12))
+
+function f4(s: string, s2?: string) { }
+>f4 : Symbol(f4, Decl(unionTypeCallSignatures3.ts, 2, 31))
+>s : Symbol(s, Decl(unionTypeCallSignatures3.ts, 3, 12))
+>s2 : Symbol(s2, Decl(unionTypeCallSignatures3.ts, 3, 22))
+
+function f5(s?: string, n?: number) { }
+>f5 : Symbol(f5, Decl(unionTypeCallSignatures3.ts, 3, 39))
+>s : Symbol(s, Decl(unionTypeCallSignatures3.ts, 4, 12))
+>n : Symbol(n, Decl(unionTypeCallSignatures3.ts, 4, 23))
+
+function f6(s?: string, ...n: number[]) { }
+>f6 : Symbol(f6, Decl(unionTypeCallSignatures3.ts, 4, 39))
+>s : Symbol(s, Decl(unionTypeCallSignatures3.ts, 5, 12))
+>n : Symbol(n, Decl(unionTypeCallSignatures3.ts, 5, 23))
+
+function f7(s: string, ...sRest: string[]) { }
+>f7 : Symbol(f7, Decl(unionTypeCallSignatures3.ts, 5, 43))
+>s : Symbol(s, Decl(unionTypeCallSignatures3.ts, 6, 12))
+>sRest : Symbol(sRest, Decl(unionTypeCallSignatures3.ts, 6, 22))
+
+var fUnion: typeof f1 | typeof f2 | typeof f3 | typeof f4 | typeof f5 | typeof f6 | typeof f7;
+>fUnion : Symbol(fUnion, Decl(unionTypeCallSignatures3.ts, 8, 3))
+>f1 : Symbol(f1, Decl(unionTypeCallSignatures3.ts, 0, 0))
+>f2 : Symbol(f2, Decl(unionTypeCallSignatures3.ts, 0, 26))
+>f3 : Symbol(f3, Decl(unionTypeCallSignatures3.ts, 1, 27))
+>f4 : Symbol(f4, Decl(unionTypeCallSignatures3.ts, 2, 31))
+>f5 : Symbol(f5, Decl(unionTypeCallSignatures3.ts, 3, 39))
+>f6 : Symbol(f6, Decl(unionTypeCallSignatures3.ts, 4, 39))
+>f7 : Symbol(f7, Decl(unionTypeCallSignatures3.ts, 5, 43))
+
+fUnion(""); // All constituents can be called by passing a single string.
+>fUnion : Symbol(fUnion, Decl(unionTypeCallSignatures3.ts, 8, 3))
+
diff --git a/tests/baselines/reference/unionTypeCallSignatures3.types b/tests/baselines/reference/unionTypeCallSignatures3.types
new file mode 100644
index 00000000000..52aae993e4a
--- /dev/null
+++ b/tests/baselines/reference/unionTypeCallSignatures3.types
@@ -0,0 +1,48 @@
+=== tests/cases/conformance/types/union/unionTypeCallSignatures3.ts ===
+function f1(s: string) { }
+>f1 : (s: string) => void
+>s : string
+
+function f2(s?: string) { }
+>f2 : (s?: string) => void
+>s : string
+
+function f3(...s: string[]) { }
+>f3 : (...s: string[]) => void
+>s : string[]
+
+function f4(s: string, s2?: string) { }
+>f4 : (s: string, s2?: string) => void
+>s : string
+>s2 : string
+
+function f5(s?: string, n?: number) { }
+>f5 : (s?: string, n?: number) => void
+>s : string
+>n : number
+
+function f6(s?: string, ...n: number[]) { }
+>f6 : (s?: string, ...n: number[]) => void
+>s : string
+>n : number[]
+
+function f7(s: string, ...sRest: string[]) { }
+>f7 : (s: string, ...sRest: string[]) => void
+>s : string
+>sRest : string[]
+
+var fUnion: typeof f1 | typeof f2 | typeof f3 | typeof f4 | typeof f5 | typeof f6 | typeof f7;
+>fUnion : ((s: string) => void) | ((s?: string) => void) | ((...s: string[]) => void) | ((s: string, s2?: string) => void) | ((s?: string, n?: number) => void) | ((s?: string, ...n: number[]) => void) | ((s: string, ...sRest: string[]) => void)
+>f1 : (s: string) => void
+>f2 : (s?: string) => void
+>f3 : (...s: string[]) => void
+>f4 : (s: string, s2?: string) => void
+>f5 : (s?: string, n?: number) => void
+>f6 : (s?: string, ...n: number[]) => void
+>f7 : (s: string, ...sRest: string[]) => void
+
+fUnion(""); // All constituents can be called by passing a single string.
+>fUnion("") : void
+>fUnion : ((s: string) => void) | ((s?: string) => void) | ((...s: string[]) => void) | ((s: string, s2?: string) => void) | ((s?: string, n?: number) => void) | ((s?: string, ...n: number[]) => void) | ((s: string, ...sRest: string[]) => void)
+>"" : string
+
diff --git a/tests/cases/conformance/types/union/unionTypeCallSignatures3.ts b/tests/cases/conformance/types/union/unionTypeCallSignatures3.ts
new file mode 100644
index 00000000000..8549315a319
--- /dev/null
+++ b/tests/cases/conformance/types/union/unionTypeCallSignatures3.ts
@@ -0,0 +1,11 @@
+function f1(s: string) { }
+function f2(s?: string) { }
+function f3(...s: string[]) { }
+function f4(s: string, s2?: string) { }
+function f5(s?: string, n?: number) { }
+function f6(s?: string, ...n: number[]) { }
+function f7(s: string, ...sRest: string[]) { }
+
+var fUnion: typeof f1 | typeof f2 | typeof f3 | typeof f4 | typeof f5 | typeof f6 | typeof f7;
+
+fUnion(""); // All constituents can be called by passing a single string.