diff --git a/flang/docs/Intrinsics.md b/flang/docs/Intrinsics.md
index 848619cb65d909..ccb93e104dab65 100644
--- a/flang/docs/Intrinsics.md
+++ b/flang/docs/Intrinsics.md
@@ -657,14 +657,6 @@ CALL CO_REDUCE
 CALL CO_SUM
 ```
 
-### Inquiry Functions
-ACCESS (GNU extension) is not supported on Windows. Otherwise:
-```
-CHARACTER(LEN=*) :: path = 'path/to/file'
-IF (ACCESS(path, 'rwx')) &
-  ...
-```
-
 ## Non-standard intrinsics
 ### PGI
 ```
diff --git a/flang/include/flang/Runtime/extensions.h b/flang/include/flang/Runtime/extensions.h
index fef651f3b2eedb..7d0952206fc195 100644
--- a/flang/include/flang/Runtime/extensions.h
+++ b/flang/include/flang/Runtime/extensions.h
@@ -44,12 +44,5 @@ std::int64_t RTNAME(Signal)(std::int64_t number, void (*handler)(int));
 // GNU extension subroutine SLEEP(SECONDS)
 void RTNAME(Sleep)(std::int64_t seconds);
 
-// GNU extension function ACCESS(NAME, MODE)
-// TODO: not supported on Windows
-#ifndef _WIN32
-std::int64_t FORTRAN_PROCEDURE_NAME(access)(const char *name,
-    std::int64_t nameLength, const char *mode, std::int64_t modeLength);
-#endif
-
 } // extern "C"
 #endif // FORTRAN_RUNTIME_EXTENSIONS_H_
diff --git a/flang/runtime/extensions.cpp b/flang/runtime/extensions.cpp
index 12498b502ae1cf..3ac98000335d7d 100644
--- a/flang/runtime/extensions.cpp
+++ b/flang/runtime/extensions.cpp
@@ -17,7 +17,6 @@
 #include "flang/Runtime/entry-names.h"
 #include "flang/Runtime/io-api.h"
 #include <chrono>
-#include <cstring>
 #include <ctime>
 #include <signal.h>
 #include <thread>
@@ -139,77 +138,5 @@ void RTNAME(Sleep)(std::int64_t seconds) {
   std::this_thread::sleep_for(std::chrono::seconds(seconds));
 }
 
-// TODO: not supported on Windows
-#ifndef _WIN32
-std::int64_t FORTRAN_PROCEDURE_NAME(access)(const char *name,
-    std::int64_t nameLength, const char *mode, std::int64_t modeLength) {
-  std::int64_t ret{-1};
-  if (nameLength <= 0 || modeLength <= 0 || !name || !mode) {
-    return ret;
-  }
-
-  // ensure name is null terminated
-  char *newName{nullptr};
-  if (name[nameLength - 1] != '\0') {
-    newName = static_cast<char *>(std::malloc(nameLength + 1));
-    std::memcpy(newName, name, nameLength);
-    newName[nameLength] = '\0';
-    name = newName;
-  }
-
-  // calculate mode
-  bool read{false};
-  bool write{false};
-  bool execute{false};
-  bool exists{false};
-  int imode{0};
-
-  for (std::int64_t i = 0; i < modeLength; ++i) {
-    switch (mode[i]) {
-    case 'r':
-      read = true;
-      break;
-    case 'w':
-      write = true;
-      break;
-    case 'x':
-      execute = true;
-      break;
-    case ' ':
-      exists = true;
-      break;
-    default:
-      // invalid mode
-      goto cleanup;
-    }
-  }
-  if (!read && !write && !execute && !exists) {
-    // invalid mode
-    goto cleanup;
-  }
-
-  if (!read && !write && !execute) {
-    imode = F_OK;
-  } else {
-    if (read) {
-      imode |= R_OK;
-    }
-    if (write) {
-      imode |= W_OK;
-    }
-    if (execute) {
-      imode |= X_OK;
-    }
-  }
-  ret = access(name, imode);
-
-cleanup:
-  if (newName) {
-    free(newName);
-  }
-  return ret;
-}
-#endif
-
 } // namespace Fortran::runtime
 } // extern "C"
diff --git a/flang/unittests/Runtime/AccessTest.cpp b/flang/unittests/Runtime/AccessTest.cpp
deleted file mode 100644
index 5c8a634192d92b..00000000000000
--- a/flang/unittests/Runtime/AccessTest.cpp
+++ /dev/null
@@ -1,390 +0,0 @@
-//===-- flang/unittests/Runtime/AccessTest.cpp ----------------------------===//
-//
-// 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
-//
-//===----------------------------------------------------------------------===//
-
-// TODO: ACCESS is not yet implemented on Windows
-#ifndef _WIN32
-
-#include "CrashHandlerFixture.h"
-#include "gtest/gtest.h"
-#include "flang/Runtime/extensions.h"
-
-#include <fcntl.h>
-#include <filesystem>
-#include <sys/stat.h>
-#include <sys/types.h>
-#include <unistd.h>
-
-namespace {
-
-struct AccessTests : public CrashHandlerFixture {};
-
-struct AccessType {
-  bool read{false};
-  bool write{false};
-  bool execute{false};
-  bool exists{false};
-};
-
-} // namespace
-
-static std::string addPIDSuffix(const char *name) {
-  std::stringstream ss;
-  ss << name;
-  ss << '.';
-
-  ss << getpid();
-
-  return ss.str();
-}
-
-static std::filesystem::path createTemporaryFile(
-    const char *name, const AccessType &accessType) {
-  std::filesystem::path path{
-      std::filesystem::temp_directory_path() / addPIDSuffix(name)};
-
-  // O_CREAT | O_EXCL enforces that this file is newly created by this call.
-  // This feels risky. If we don't have permission to create files in the
-  // temporary directory or if the files already exist, the test will fail.
-  // But we can't use std::tmpfile() because we need a path to the file and
-  // to control the filesystem permissions
-  mode_t mode{0};
-  if (accessType.read) {
-    mode |= S_IRUSR;
-  }
-  if (accessType.write) {
-    mode |= S_IWUSR;
-  }
-  if (accessType.execute) {
-    mode |= S_IXUSR;
-  }
-
-  int file = open(path.c_str(), O_CREAT | O_EXCL, mode);
-  if (file == -1) {
-    return {};
-  }
-
-  close(file);
-
-  return path;
-}
-
-static std::int64_t callAccess(
-    const std::filesystem::path &path, const AccessType &accessType) {
-  const char *cpath{path.c_str()};
-  std::int64_t pathlen = std::strlen(cpath);
-
-  std::string mode;
-  if (accessType.read) {
-    mode += 'r';
-  }
-  if (accessType.write) {
-    mode += 'w';
-  }
-  if (accessType.execute) {
-    mode += 'x';
-  }
-  if (accessType.exists) {
-    mode += ' ';
-  }
-
-  const char *cmode = mode.c_str();
-  std::int64_t modelen = std::strlen(cmode);
-
-  return FORTRAN_PROCEDURE_NAME(access)(cpath, pathlen, cmode, modelen);
-}
-
-TEST(AccessTests, TestExists) {
-  AccessType accessType;
-  accessType.exists = true;
-
-  std::filesystem::path path = createTemporaryFile(__func__, accessType);
-  ASSERT_FALSE(path.empty());
-
-  std::int64_t res = callAccess(path, accessType);
-
-  std::filesystem::remove(path);
-
-  ASSERT_EQ(res, 0);
-}
-
-TEST(AccessTests, TestNotExists) {
-  std::filesystem::path nonExistant{addPIDSuffix(__func__)};
-  ASSERT_FALSE(std::filesystem::exists(nonExistant));
-
-  AccessType accessType;
-  accessType.exists = true;
-  std::int64_t res = callAccess(nonExistant, accessType);
-
-  ASSERT_NE(res, 0);
-}
-
-TEST(AccessTests, TestRead) {
-  AccessType accessType;
-  accessType.read = true;
-
-  std::filesystem::path path = createTemporaryFile(__func__, accessType);
-  ASSERT_FALSE(path.empty());
-
-  std::int64_t res = callAccess(path, accessType);
-
-  std::filesystem::remove(path);
-
-  ASSERT_EQ(res, 0);
-}
-
-TEST(AccessTests, TestNotRead) {
-  AccessType accessType;
-  accessType.read = false;
-
-  std::filesystem::path path = createTemporaryFile(__func__, accessType);
-  ASSERT_FALSE(path.empty());
-
-  accessType.read = true;
-  std::int64_t res = callAccess(path, accessType);
-
-  std::filesystem::remove(path);
-
-  ASSERT_NE(res, 0);
-}
-
-TEST(AccessTests, TestWrite) {
-  AccessType accessType;
-  accessType.write = true;
-
-  std::filesystem::path path = createTemporaryFile(__func__, accessType);
-  ASSERT_FALSE(path.empty());
-
-  std::int64_t res = callAccess(path, accessType);
-
-  std::filesystem::remove(path);
-
-  ASSERT_EQ(res, 0);
-}
-
-TEST(AccessTests, TestNotWrite) {
-  AccessType accessType;
-  accessType.write = false;
-
-  std::filesystem::path path = createTemporaryFile(__func__, accessType);
-  ASSERT_FALSE(path.empty());
-
-  accessType.write = true;
-  std::int64_t res = callAccess(path, accessType);
-
-  std::filesystem::remove(path);
-
-  ASSERT_NE(res, 0);
-}
-
-TEST(AccessTests, TestReadWrite) {
-  AccessType accessType;
-  accessType.read = true;
-  accessType.write = true;
-
-  std::filesystem::path path = createTemporaryFile(__func__, accessType);
-  ASSERT_FALSE(path.empty());
-
-  std::int64_t res = callAccess(path, accessType);
-
-  std::filesystem::remove(path);
-
-  ASSERT_EQ(res, 0);
-}
-
-TEST(AccessTests, TestNotReadWrite0) {
-  AccessType accessType;
-  accessType.read = false;
-  accessType.write = false;
-
-  std::filesystem::path path = createTemporaryFile(__func__, accessType);
-  ASSERT_FALSE(path.empty());
-
-  accessType.read = true;
-  accessType.write = true;
-  std::int64_t res = callAccess(path, accessType);
-
-  std::filesystem::remove(path);
-
-  ASSERT_NE(res, 0);
-}
-
-TEST(AccessTests, TestNotReadWrite1) {
-  AccessType accessType;
-  accessType.read = true;
-  accessType.write = false;
-
-  std::filesystem::path path = createTemporaryFile(__func__, accessType);
-  ASSERT_FALSE(path.empty());
-
-  accessType.read = true;
-  accessType.write = true;
-  std::int64_t res = callAccess(path, accessType);
-
-  std::filesystem::remove(path);
-
-  ASSERT_NE(res, 0);
-}
-
-TEST(AccessTests, TestNotReadWrite2) {
-  AccessType accessType;
-  accessType.read = false;
-  accessType.write = true;
-
-  std::filesystem::path path = createTemporaryFile(__func__, accessType);
-  ASSERT_FALSE(path.empty());
-
-  accessType.read = true;
-  accessType.write = true;
-  std::int64_t res = callAccess(path, accessType);
-
-  std::filesystem::remove(path);
-
-  ASSERT_NE(res, 0);
-}
-
-TEST(AccessTests, TestExecute) {
-  AccessType accessType;
-  accessType.execute = true;
-
-  std::filesystem::path path = createTemporaryFile(__func__, accessType);
-  ASSERT_FALSE(path.empty());
-
-  std::int64_t res = callAccess(path, accessType);
-
-  std::filesystem::remove(path);
-
-  ASSERT_EQ(res, 0);
-}
-
-TEST(AccessTests, TestNotExecute) {
-  AccessType accessType;
-  accessType.execute = false;
-
-  std::filesystem::path path = createTemporaryFile(__func__, accessType);
-  ASSERT_FALSE(path.empty());
-
-  accessType.execute = true;
-  std::int64_t res = callAccess(path, accessType);
-
-  std::filesystem::remove(path);
-
-  ASSERT_NE(res, 0);
-}
-
-TEST(AccessTests, TestRWX) {
-  AccessType accessType;
-  accessType.read = true;
-  accessType.write = true;
-  accessType.execute = true;
-
-  std::filesystem::path path = createTemporaryFile(__func__, accessType);
-  ASSERT_FALSE(path.empty());
-
-  std::int64_t res = callAccess(path, accessType);
-
-  std::filesystem::remove(path);
-
-  ASSERT_EQ(res, 0);
-}
-
-TEST(AccessTests, TestNotRWX0) {
-  AccessType accessType;
-  accessType.read = false;
-  accessType.write = false;
-  accessType.execute = false;
-
-  std::filesystem::path path = createTemporaryFile(__func__, accessType);
-  ASSERT_FALSE(path.empty());
-
-  accessType.read = true;
-  accessType.write = true;
-  accessType.execute = true;
-  std::int64_t res = callAccess(path, accessType);
-
-  std::filesystem::remove(path);
-
-  ASSERT_NE(res, 0);
-}
-
-TEST(AccessTests, TestNotRWX1) {
-  AccessType accessType;
-  accessType.read = true;
-  accessType.write = false;
-  accessType.execute = false;
-
-  std::filesystem::path path = createTemporaryFile(__func__, accessType);
-  ASSERT_FALSE(path.empty());
-
-  accessType.read = true;
-  accessType.write = true;
-  accessType.execute = true;
-  std::int64_t res = callAccess(path, accessType);
-
-  std::filesystem::remove(path);
-
-  ASSERT_NE(res, 0);
-}
-
-TEST(AccessTests, TestNotRWX2) {
-  AccessType accessType;
-  accessType.read = true;
-  accessType.write = true;
-  accessType.execute = false;
-
-  std::filesystem::path path = createTemporaryFile(__func__, accessType);
-  ASSERT_FALSE(path.empty());
-
-  accessType.read = true;
-  accessType.write = true;
-  accessType.execute = true;
-  std::int64_t res = callAccess(path, accessType);
-
-  std::filesystem::remove(path);
-
-  ASSERT_NE(res, 0);
-}
-
-TEST(AccessTests, TestNotRWX3) {
-  AccessType accessType;
-  accessType.read = true;
-  accessType.write = false;
-  accessType.execute = true;
-
-  std::filesystem::path path = createTemporaryFile(__func__, accessType);
-  ASSERT_FALSE(path.empty());
-
-  accessType.read = true;
-  accessType.write = true;
-  accessType.execute = true;
-  std::int64_t res = callAccess(path, accessType);
-
-  std::filesystem::remove(path);
-
-  ASSERT_NE(res, 0);
-}
-
-TEST(AccessTests, TestNotRWX4) {
-  AccessType accessType;
-  accessType.read = false;
-  accessType.write = true;
-  accessType.execute = true;
-
-  std::filesystem::path path = createTemporaryFile(__func__, accessType);
-  ASSERT_FALSE(path.empty());
-
-  accessType.read = true;
-  accessType.write = true;
-  accessType.execute = true;
-  std::int64_t res = callAccess(path, accessType);
-
-  std::filesystem::remove(path);
-
-  ASSERT_NE(res, 0);
-}
-
-#endif // !_WIN32
diff --git a/flang/unittests/Runtime/CMakeLists.txt b/flang/unittests/Runtime/CMakeLists.txt
index f7caacad3a598f..23f02aa751246b 100644
--- a/flang/unittests/Runtime/CMakeLists.txt
+++ b/flang/unittests/Runtime/CMakeLists.txt
@@ -1,5 +1,4 @@
 add_flang_unittest(FlangRuntimeTests
-  AccessTest.cpp
   Allocatable.cpp
   ArrayConstructor.cpp
   BufferTest.cpp