diff --git a/clang/lib/Format/TokenAnnotator.cpp b/clang/lib/Format/TokenAnnotator.cpp
--- a/clang/lib/Format/TokenAnnotator.cpp
+++ b/clang/lib/Format/TokenAnnotator.cpp
@@ -3115,6 +3115,16 @@
                        Keywords.kw_lock))
         return Style.SpaceBeforeParens == FormatStyle::SBPO_ControlStatements ||
                spaceRequiredBeforeParens(Right);
+
+    // space between method modifier and opening parenthesis of a tuple return
+    // type
+    if (Left.isOneOf(tok::kw_public, tok::kw_private, tok::kw_protected,
+                     tok::kw_virtual, tok::kw_extern, tok::kw_static,
+                     Keywords.kw_internal, Keywords.kw_abstract,
+                     Keywords.kw_sealed, Keywords.kw_override,
+                     Keywords.kw_async, Keywords.kw_unsafe) &&
+        Right.is(tok::l_paren))
+      return true;
   } else if (Style.Language == FormatStyle::LK_JavaScript) {
     if (Left.is(TT_JsFatArrow))
       return true;
diff --git a/clang/unittests/Format/FormatTestCSharp.cpp b/clang/unittests/Format/FormatTestCSharp.cpp
--- a/clang/unittests/Format/FormatTestCSharp.cpp
+++ b/clang/unittests/Format/FormatTestCSharp.cpp
@@ -777,6 +777,20 @@
   verifyFormat(R"(private float[ , ] Values;)", Style);
   verifyFormat(R"(string dirPath = args?[ 0 ];)", Style);
   verifyFormat(R"(char[ ,, ] rawCharArray = MakeCharacterGrid();)", Style);
+
+  // Method returning tuple
+  verifyFormat(R"(public (string name, int age) methodTuple() {})", Style);
+  verifyFormat(R"(private (string name, int age) methodTuple() {})", Style);
+  verifyFormat(R"(protected (string name, int age) methodTuple() {})", Style);
+  verifyFormat(R"(virtual (string name, int age) methodTuple() {})", Style);
+  verifyFormat(R"(extern (string name, int age) methodTuple() {})", Style);
+  verifyFormat(R"(static (string name, int age) methodTuple() {})", Style);
+  verifyFormat(R"(internal (string name, int age) methodTuple() {})", Style);
+  verifyFormat(R"(abstract (string name, int age) methodTuple() {})", Style);
+  verifyFormat(R"(sealed (string name, int age) methodTuple() {})", Style);
+  verifyFormat(R"(override (string name, int age) methodTuple() {})", Style);
+  verifyFormat(R"(async (string name, int age) methodTuple() {})", Style);
+  verifyFormat(R"(unsafe (string name, int age) methodTuple() {})", Style);
 }
 
 TEST_F(FormatTestCSharp, CSharpNullableTypes) {