diff --git a/clang/docs/ClangFormatStyleOptions.rst b/clang/docs/ClangFormatStyleOptions.rst
--- a/clang/docs/ClangFormatStyleOptions.rst
+++ b/clang/docs/ClangFormatStyleOptions.rst
@@ -154,6 +154,13 @@
   * ``GNU``
     A style complying with the `GNU coding standards
     <https://www.gnu.org/prep/standards/standards.html>`_
+  * ``File``
+    Not a real style, but allows to use the ``.clang-format`` file from the
+    parent directory (or its parent if there is none). If there is no parent
+    file fount it falls back to the ``LLVM`` style.
+
+    With this option you can overwrite some parts of your main style for your
+    subdirectories.
 
 .. START_FORMAT_STYLE_OPTIONS
 
diff --git a/clang/docs/ReleaseNotes.rst b/clang/docs/ReleaseNotes.rst
--- a/clang/docs/ReleaseNotes.rst
+++ b/clang/docs/ReleaseNotes.rst
@@ -303,6 +303,8 @@
 - Option ``SpacesInLineCommentPrefix`` has been added to control the
   number of spaces in a line comments prefix.
 
+- ``BasedOnStyle: File`` allows to use the ``.clang-format`` of the
+  parent directories to overwrite only parts of it.
 
 libclang
 --------
diff --git a/clang/include/clang/Format/Format.h b/clang/include/clang/Format/Format.h
--- a/clang/include/clang/Format/Format.h
+++ b/clang/include/clang/Format/Format.h
@@ -52,6 +52,11 @@
 /// The ``FormatStyle`` is used to configure the formatting to follow
 /// specific guidelines.
 struct FormatStyle {
+  // If the BasedOn: was File and this style needs the file from the parent
+  // directories. It is not part of the actual style for formatting. Thus the //
+  // instead of ///.
+  bool NeedsParentFile;
+
   /// The extra indent or outdent of access modifiers, e.g. ``public:``.
   int AccessModifierOffset;
 
diff --git a/clang/lib/Format/Format.cpp b/clang/lib/Format/Format.cpp
--- a/clang/lib/Format/Format.cpp
+++ b/clang/lib/Format/Format.cpp
@@ -867,6 +867,7 @@
 
 FormatStyle getLLVMStyle(FormatStyle::LanguageKind Language) {
   FormatStyle LLVMStyle;
+  LLVMStyle.NeedsParentFile = false;
   LLVMStyle.Language = Language;
   LLVMStyle.AccessModifierOffset = -2;
   LLVMStyle.AlignEscapedNewlines = FormatStyle::ENAS_Right;
@@ -1341,6 +1342,8 @@
     *Style = getMicrosoftStyle(Language);
   } else if (Name.equals_lower("none")) {
     *Style = getNoStyle();
+  } else if (Name.equals_lower("file")) {
+    Style->NeedsParentFile = true;
   } else {
     return false;
   }
@@ -2946,6 +2949,36 @@
         }
         LLVM_DEBUG(llvm::dbgs()
                    << "Using configuration file " << ConfigFile << "\n");
+
+        if (Style.NeedsParentFile) {
+          LLVM_DEBUG(llvm::dbgs() << "Needs a parent configuration\n");
+
+          auto ParentDirectory = llvm::sys::path::parent_path(Directory);
+
+          if (!ParentDirectory.empty()) {
+            SmallString<128> FileForLanguage(ParentDirectory);
+            llvm::sys::path::append(FileForLanguage,
+                                    llvm::sys::path::filename(FileName));
+            if (auto OuterStyle = getStyle(DefaultFormatStyle, FileForLanguage,
+                                           FallbackStyleName, Code, FS,
+                                           AllowUnknownOptions)) {
+              parseConfiguration(*Text.get(), &*OuterStyle,
+                                 AllowUnknownOptions);
+              return *OuterStyle;
+            } else {
+              LLVM_DEBUG(
+                  llvm::dbgs()
+                  << "Error while parsing parent: " << OuterStyle.takeError()
+                  << "\nUsing FallbackStyle:" << FallbackStyleName << "\n");
+            }
+          } else {
+            LLVM_DEBUG(llvm::dbgs() << "No parent left, using FallbackStyle:"
+                                    << FallbackStyleName << "\n");
+          }
+
+          return FallbackStyle;
+        }
+
         return Style;
       }
     }
diff --git a/clang/unittests/Format/FormatTest.cpp b/clang/unittests/Format/FormatTest.cpp
--- a/clang/unittests/Format/FormatTest.cpp
+++ b/clang/unittests/Format/FormatTest.cpp
@@ -16667,6 +16667,63 @@
   auto StyleTd = getStyle("file", "x.td", "llvm", "", &FS);
   ASSERT_TRUE((bool)StyleTd);
   ASSERT_EQ(*StyleTd, getLLVMStyle(FormatStyle::LK_TableGen));
+
+  // Test 9.1: overwriting a file style, when parent no file exists with no
+  // fallback style
+  ASSERT_TRUE(FS.addFile("/e/sub/.clang-format", 0,
+                         llvm::MemoryBuffer::getMemBuffer("BasedOnStyle: File\n"
+                                                          "ColumnLimit: 20")));
+  ASSERT_TRUE(FS.addFile("/e/sub/code.cpp", 0,
+                         llvm::MemoryBuffer::getMemBuffer("int i;")));
+  auto Style9 = getStyle("file", "/e/sub/code.cpp", "none", "", &FS);
+  ASSERT_TRUE(static_cast<bool>(Style9));
+  ASSERT_EQ(*Style9, [] {
+    auto Style = getNoStyle();
+    Style.ColumnLimit = 20;
+    return Style;
+  }());
+
+  // Test 9.2: with LLVM fallback style
+  Style9 = getStyle("file", "/e/sub/code.cpp", "LLVM", "", &FS);
+  ASSERT_TRUE(static_cast<bool>(Style9));
+  ASSERT_EQ(*Style9, [] {
+    auto Style = getLLVMStyle();
+    Style.ColumnLimit = 20;
+    return Style;
+  }());
+
+  // Test 9.3: with a parent file
+  ASSERT_TRUE(
+      FS.addFile("/e/.clang-format", 0,
+                 llvm::MemoryBuffer::getMemBuffer("BasedOnStyle: Google\n"
+                                                  "UseTab: Always")));
+  Style9 = getStyle("file", "/e/sub/code.cpp", "none", "", &FS);
+  ASSERT_TRUE(static_cast<bool>(Style9));
+  ASSERT_EQ(*Style9, [] {
+    auto Style = getGoogleStyle();
+    Style.ColumnLimit = 20;
+    Style.UseTab = FormatStyle::UT_Always;
+    return Style;
+  }());
+
+  // Test 9.4: propagate more than one level
+  ASSERT_TRUE(FS.addFile("/e/sub/sub/code.cpp", 0,
+                         llvm::MemoryBuffer::getMemBuffer("int i;")));
+  ASSERT_TRUE(FS.addFile("/e/sub/sub/.clang-format", 0,
+                         llvm::MemoryBuffer::getMemBuffer(
+                             "BasedOnStyle: File\n"
+                             "WhitespaceSensitiveMacros: ['FOO', 'BAR']")));
+  std::vector<std::string> NonDefaultWhiteSpaceMacros{"FOO", "BAR"};
+  ASSERT_NE(Style9->WhitespaceSensitiveMacros, NonDefaultWhiteSpaceMacros);
+  Style9 = getStyle("file", "/e/sub/sub/code.cpp", "none", "", &FS);
+  ASSERT_TRUE(static_cast<bool>(Style9));
+  ASSERT_EQ(*Style9, [&NonDefaultWhiteSpaceMacros] {
+    auto Style = getGoogleStyle();
+    Style.ColumnLimit = 20;
+    Style.UseTab = FormatStyle::UT_Always;
+    Style.WhitespaceSensitiveMacros = NonDefaultWhiteSpaceMacros;
+    return Style;
+  }());
 }
 
 TEST_F(ReplacementTest, FormatCodeAfterReplacements) {