diff --git a/clang/docs/ReleaseNotes.rst b/clang/docs/ReleaseNotes.rst
index 9bc96f4dc1e961..dcc2eaf4b202f9 100644
--- a/clang/docs/ReleaseNotes.rst
+++ b/clang/docs/ReleaseNotes.rst
@@ -188,6 +188,11 @@ Attribute Changes in Clang
   supported the ability to specify a message in the attribute, so there were no
   changes to the attribute behavior.
 
+- Updated the value returned by ``__has_c_attribute(fallthrough)`` to ``201910L``
+  based on the final date specified by the C2x committee draft. We previously
+  used ``201904L`` (the date the proposal was seen by the committee) by mistake.
+  There were no other changes to the attribute behavior.
+
 Windows Support
 ---------------
 - For the MinGW driver, added the options ``-mguard=none``, ``-mguard=cf`` and
diff --git a/clang/include/clang/Basic/Attr.td b/clang/include/clang/Basic/Attr.td
index 48c7791ebe330e..2e3297b72a8cfb 100644
--- a/clang/include/clang/Basic/Attr.td
+++ b/clang/include/clang/Basic/Attr.td
@@ -1412,7 +1412,7 @@ def ExtVectorType : Attr {
 
 def FallThrough : StmtAttr {
   let Spellings = [CXX11<"", "fallthrough", 201603>,
-                   C2x<"", "fallthrough", 201904>,
+                   C2x<"", "fallthrough", 201910>,
                    CXX11<"clang", "fallthrough">, GCC<"fallthrough">];
   // The attribute only applies to a NullStmt, but we have special fix-it
   // behavior if applied to a case label.
diff --git a/clang/test/Preprocessor/has_c_attribute.c b/clang/test/Preprocessor/has_c_attribute.c
index 401daa72b85b18..1da4d0541e6e0d 100644
--- a/clang/test/Preprocessor/has_c_attribute.c
+++ b/clang/test/Preprocessor/has_c_attribute.c
@@ -3,7 +3,7 @@
 
 #define C2x(x) x: __has_c_attribute(x)
 
-// CHECK: fallthrough: 201904L
+// CHECK: fallthrough: 201910L
 C2x(fallthrough)
 
 // CHECK: __nodiscard__: 202003L
diff --git a/clang/test/Sema/c2x-fallthrough.c b/clang/test/Sema/c2x-fallthrough.c
index baa62aa8f14011..092d5285f80bac 100644
--- a/clang/test/Sema/c2x-fallthrough.c
+++ b/clang/test/Sema/c2x-fallthrough.c
@@ -1,4 +1,7 @@
-// RUN: %clang_cc1 -fsyntax-only -fdouble-square-bracket-attributes -verify %s
+// RUN: %clang_cc1 -fsyntax-only -std=c2x -verify %s
+
+// This is the latest version of fallthrough that we support.
+_Static_assert(__has_c_attribute(fallthrough) == 201910L);
 
 void f(int n) {
   switch (n) {