diff --git a/libcxx/docs/ReleaseNotes/19.rst b/libcxx/docs/ReleaseNotes/19.rst
index 17a0415a8ad43..ecf6569cf43fb 100644
--- a/libcxx/docs/ReleaseNotes/19.rst
+++ b/libcxx/docs/ReleaseNotes/19.rst
@@ -56,7 +56,7 @@ Deprecations and Removals
   the LLVM 19 release while also issuing a deprecation warning). See :ref:`the hardening documentation
   <using-hardening-modes>` for more details.
 
-- TODO: The base template for ``std::char_traits`` has been removed in LLVM 19. If you are using ``std::char_traits`` with
+- The base template for ``std::char_traits`` has been removed in LLVM 19. If you are using ``std::char_traits`` with
   types other than ``char``, ``wchar_t``, ``char8_t``, ``char16_t``, ``char32_t`` or a custom character type for which you
   specialized ``std::char_traits``, your code will stop working. The Standard does not mandate that a base template is
   provided, and such a base template is bound to be incorrect for some types, which could currently cause unexpected behavior
diff --git a/libcxx/include/__string/char_traits.h b/libcxx/include/__string/char_traits.h
index e3563c57fea0c..8ea9625d07183 100644
--- a/libcxx/include/__string/char_traits.h
+++ b/libcxx/include/__string/char_traits.h
@@ -72,106 +72,6 @@ exposition-only to document what members a char_traits specialization should pro
 };
 */
 
-//
-// Temporary extension to provide a base template for std::char_traits.
-// TODO(LLVM-19): Remove this class.
-//
-#if !defined(_LIBCPP_CHAR_TRAITS_REMOVE_BASE_SPECIALIZATION)
-template <class _CharT>
-struct _LIBCPP_DEPRECATED_(
-    "char_traits<T> for T not equal to char, wchar_t, char8_t, char16_t or char32_t is non-standard and is provided "
-    "for a temporary period. It will be removed in LLVM 19, so please migrate off of it.") char_traits {
-  using char_type  = _CharT;
-  using int_type   = int;
-  using off_type   = streamoff;
-  using pos_type   = streampos;
-  using state_type = mbstate_t;
-
-  static inline void _LIBCPP_CONSTEXPR_SINCE_CXX17 _LIBCPP_HIDE_FROM_ABI
-  assign(char_type& __c1, const char_type& __c2) _NOEXCEPT {
-    __c1 = __c2;
-  }
-  static inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR bool eq(char_type __c1, char_type __c2) _NOEXCEPT {
-    return __c1 == __c2;
-  }
-  static inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR bool lt(char_type __c1, char_type __c2) _NOEXCEPT {
-    return __c1 < __c2;
-  }
-
-  static _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 int
-  compare(const char_type* __s1, const char_type* __s2, size_t __n) {
-    for (; __n; --__n, ++__s1, ++__s2) {
-      if (lt(*__s1, *__s2))
-        return -1;
-      if (lt(*__s2, *__s1))
-        return 1;
-    }
-    return 0;
-  }
-  _LIBCPP_HIDE_FROM_ABI static _LIBCPP_CONSTEXPR_SINCE_CXX17 size_t length(const char_type* __s) {
-    size_t __len = 0;
-    for (; !eq(*__s, char_type(0)); ++__s)
-      ++__len;
-    return __len;
-  }
-  _LIBCPP_HIDE_FROM_ABI static _LIBCPP_CONSTEXPR_SINCE_CXX17 const char_type*
-  find(const char_type* __s, size_t __n, const char_type& __a) {
-    for (; __n; --__n) {
-      if (eq(*__s, __a))
-        return __s;
-      ++__s;
-    }
-    return nullptr;
-  }
-  static _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 char_type*
-  move(char_type* __s1, const char_type* __s2, size_t __n) {
-    if (__n == 0)
-      return __s1;
-    char_type* __r = __s1;
-    if (__s1 < __s2) {
-      for (; __n; --__n, ++__s1, ++__s2)
-        assign(*__s1, *__s2);
-    } else if (__s2 < __s1) {
-      __s1 += __n;
-      __s2 += __n;
-      for (; __n; --__n)
-        assign(*--__s1, *--__s2);
-    }
-    return __r;
-  }
-  _LIBCPP_HIDE_FROM_ABI static _LIBCPP_CONSTEXPR_SINCE_CXX20 char_type*
-  copy(char_type* __s1, const char_type* __s2, size_t __n) {
-    _LIBCPP_ASSERT_NON_OVERLAPPING_RANGES(!std::__is_pointer_in_range(__s1, __s1 + __n, __s2),
-                                          "char_traits::copy: source and destination ranges overlap");
-    char_type* __r = __s1;
-    for (; __n; --__n, ++__s1, ++__s2)
-      assign(*__s1, *__s2);
-    return __r;
-  }
-  _LIBCPP_HIDE_FROM_ABI static _LIBCPP_CONSTEXPR_SINCE_CXX20 char_type*
-  assign(char_type* __s, size_t __n, char_type __a) {
-    char_type* __r = __s;
-    for (; __n; --__n, ++__s)
-      assign(*__s, __a);
-    return __r;
-  }
-
-  static inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR int_type not_eof(int_type __c) _NOEXCEPT {
-    return eq_int_type(__c, eof()) ? ~eof() : __c;
-  }
-  static inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR char_type to_char_type(int_type __c) _NOEXCEPT {
-    return char_type(__c);
-  }
-  static inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR int_type to_int_type(char_type __c) _NOEXCEPT {
-    return int_type(__c);
-  }
-  static inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR bool eq_int_type(int_type __c1, int_type __c2) _NOEXCEPT {
-    return __c1 == __c2;
-  }
-  static inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR int_type eof() _NOEXCEPT { return int_type(EOF); }
-};
-#endif // !defined(_LIBCPP_CHAR_TRAITS_REMOVE_BASE_SPECIALIZATION)
-
 // char_traits<char>
 
 template <>
diff --git a/libcxx/test/libcxx/strings/char.traits/char.traits.specializations/arbitrary_char_type.deprecated.verify.cpp b/libcxx/test/libcxx/strings/char.traits/char.traits.specializations/arbitrary_char_type.deprecated.verify.cpp
deleted file mode 100644
index ec6f34ef5462e..0000000000000
--- a/libcxx/test/libcxx/strings/char.traits/char.traits.specializations/arbitrary_char_type.deprecated.verify.cpp
+++ /dev/null
@@ -1,21 +0,0 @@
-//===----------------------------------------------------------------------===//
-//
-// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
-// See https://llvm.org/LICENSE.txt for license information.
-// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
-//
-//===----------------------------------------------------------------------===//
-
-// <string>
-
-// template<> struct char_traits<T> for arbitrary T
-
-// Make sure we issue deprecation warnings.
-
-#include <string>
-
-void f() {
-    std::char_traits<unsigned char> t1; (void)t1; // expected-warning{{'char_traits<unsigned char>' is deprecated}}
-    std::char_traits<signed char> t2; (void)t2; // expected-warning{{'char_traits<signed char>' is deprecated}}
-    std::char_traits<unsigned long> t3; (void)t3; // expected-warning{{'char_traits<unsigned long>' is deprecated}}
-}
diff --git a/libcxx/test/libcxx/strings/char.traits/char.traits.specializations/arbitrary_char_type.pass.cpp b/libcxx/test/libcxx/strings/char.traits/char.traits.specializations/arbitrary_char_type.pass.cpp
deleted file mode 100644
index c2de29d22b2fe..0000000000000
--- a/libcxx/test/libcxx/strings/char.traits/char.traits.specializations/arbitrary_char_type.pass.cpp
+++ /dev/null
@@ -1,146 +0,0 @@
-//===----------------------------------------------------------------------===//
-//
-// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
-// See https://llvm.org/LICENSE.txt for license information.
-// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
-//
-//===----------------------------------------------------------------------===//
-
-// <string>
-
-// template<> struct char_traits<T> for arbitrary T
-
-// Non-standard but provided temporarily for users to migrate.
-
-// ADDITIONAL_COMPILE_FLAGS: -Wno-deprecated
-
-#include <string>
-#include <cassert>
-#include <type_traits>
-
-#include "test_macros.h"
-
-template <class Char>
-TEST_CONSTEXPR_CXX20 bool test() {
-    static_assert(std::is_same<typename std::char_traits<Char>::char_type, Char>::value, "");
-    static_assert(std::is_same<typename std::char_traits<Char>::int_type, int>::value, "");
-    static_assert(std::is_same<typename std::char_traits<Char>::off_type, std::streamoff>::value, "");
-    static_assert(std::is_same<typename std::char_traits<Char>::pos_type, std::streampos>::value, "");
-    static_assert(std::is_same<typename std::char_traits<Char>::state_type, std::mbstate_t>::value, "");
-
-    assert(std::char_traits<Char>::to_int_type(Char('a')) == Char('a'));
-    assert(std::char_traits<Char>::to_int_type(Char('A')) == Char('A'));
-    assert(std::char_traits<Char>::to_int_type(0) == 0);
-
-    assert(std::char_traits<Char>::to_char_type(Char('a')) == Char('a'));
-    assert(std::char_traits<Char>::to_char_type(Char('A')) == Char('A'));
-    assert(std::char_traits<Char>::to_char_type(0) == 0);
-
-    assert(std::char_traits<Char>::eof() == EOF);
-
-    assert(std::char_traits<Char>::not_eof(Char('a')) == Char('a'));
-    assert(std::char_traits<Char>::not_eof(Char('A')) == Char('A'));
-    assert(std::char_traits<Char>::not_eof(0) == 0);
-    assert(std::char_traits<Char>::not_eof(std::char_traits<Char>::eof()) !=
-           std::char_traits<Char>::eof());
-
-    assert(std::char_traits<Char>::lt(Char('\0'), Char('A')) == (Char('\0') < Char('A')));
-    assert(std::char_traits<Char>::lt(Char('A'), Char('\0')) == (Char('A') < Char('\0')));
-    assert(std::char_traits<Char>::lt(Char('a'), Char('a')) == (Char('a') < Char('a')));
-    assert(std::char_traits<Char>::lt(Char('A'), Char('a')) == (Char('A') < Char('a')));
-    assert(std::char_traits<Char>::lt(Char('a'), Char('A')) == (Char('a') < Char('A')));
-
-    assert( std::char_traits<Char>::eq(Char('a'), Char('a')));
-    assert(!std::char_traits<Char>::eq(Char('a'), Char('A')));
-
-    assert( std::char_traits<Char>::eq_int_type(Char('a'), Char('a')));
-    assert(!std::char_traits<Char>::eq_int_type(Char('a'), Char('A')));
-    assert(!std::char_traits<Char>::eq_int_type(std::char_traits<Char>::eof(), Char('A')));
-    assert( std::char_traits<Char>::eq_int_type(std::char_traits<Char>::eof(), std::char_traits<Char>::eof()));
-
-    {
-        Char s1[] = {1, 2, 3, 0};
-        Char s2[] = {0};
-        assert(std::char_traits<Char>::length(s1) == 3);
-        assert(std::char_traits<Char>::length(s2) == 0);
-    }
-
-    {
-        Char s1[] = {1, 2, 3};
-        assert(std::char_traits<Char>::find(s1, 3, Char(1)) == s1);
-        assert(std::char_traits<Char>::find(s1, 3, Char(2)) == s1+1);
-        assert(std::char_traits<Char>::find(s1, 3, Char(3)) == s1+2);
-        assert(std::char_traits<Char>::find(s1, 3, Char(4)) == 0);
-        assert(std::char_traits<Char>::find(s1, 3, Char(0)) == 0);
-        assert(std::char_traits<Char>::find(NULL, 0, Char(0)) == 0);
-    }
-
-    {
-        Char s1[] = {1, 2, 3};
-        Char s2[3] = {0};
-        assert(std::char_traits<Char>::copy(s2, s1, 3) == s2);
-        assert(s2[0] == Char(1));
-        assert(s2[1] == Char(2));
-        assert(s2[2] == Char(3));
-        assert(std::char_traits<Char>::copy(NULL, s1, 0) == NULL);
-        assert(std::char_traits<Char>::copy(s1, NULL, 0) == s1);
-    }
-
-    {
-        Char s1[] = {1, 2, 3};
-        assert(std::char_traits<Char>::move(s1, s1+1, 2) == s1);
-        assert(s1[0] == Char(2));
-        assert(s1[1] == Char(3));
-        assert(s1[2] == Char(3));
-        s1[2] = Char(0);
-        assert(std::char_traits<Char>::move(s1+1, s1, 2) == s1+1);
-        assert(s1[0] == Char(2));
-        assert(s1[1] == Char(2));
-        assert(s1[2] == Char(3));
-        assert(std::char_traits<Char>::move(NULL, s1, 0) == NULL);
-        assert(std::char_traits<Char>::move(s1, NULL, 0) == s1);
-    }
-
-    {
-        Char s1[] = {0};
-        assert(std::char_traits<Char>::compare(s1, s1, 0) == 0);
-        assert(std::char_traits<Char>::compare(NULL, NULL, 0) == 0);
-
-        Char s2[] = {1, 0};
-        Char s3[] = {2, 0};
-        assert(std::char_traits<Char>::compare(s2, s2, 1) == 0);
-        assert(std::char_traits<Char>::compare(s2, s3, 1) < 0);
-        assert(std::char_traits<Char>::compare(s3, s2, 1) > 0);
-    }
-
-    {
-        Char s2[3] = {0};
-        assert(std::char_traits<Char>::assign(s2, 3, Char(5)) == s2);
-        assert(s2[0] == Char(5));
-        assert(s2[1] == Char(5));
-        assert(s2[2] == Char(5));
-        assert(std::char_traits<Char>::assign(NULL, 0, Char(5)) == NULL);
-    }
-
-    {
-        Char c = Char('\0');
-        std::char_traits<Char>::assign(c, Char('a'));
-        assert(c == Char('a'));
-    }
-
-    return true;
-}
-
-int main(int, char**) {
-    test<unsigned char>();
-    test<signed char>();
-    test<unsigned long>();
-
-#if TEST_STD_VER > 17
-    static_assert(test<unsigned char>());
-    static_assert(test<signed char>());
-    static_assert(test<unsigned long>());
-#endif
-
-  return 0;
-}