diff --git a/modules/rostests/apitests/kernel32/CMakeLists.txt b/modules/rostests/apitests/kernel32/CMakeLists.txt
index db715423fed..57a4e1858b5 100644
--- a/modules/rostests/apitests/kernel32/CMakeLists.txt
+++ b/modules/rostests/apitests/kernel32/CMakeLists.txt
@@ -37,6 +37,7 @@ list(APPEND SOURCE
     Pipes.c
     PrivMoveFileIdentityW.c
     QueueUserAPC.c
+    ReadFile.c
     SetComputerNameExW.c
     SetConsoleWindowInfo.c
     SetCurrentDirectory.c
@@ -45,7 +46,9 @@ list(APPEND SOURCE
     TerminateProcess.c
     TunnelCache.c
     UEFIFirmware.c
-    WideCharToMultiByte.c)
+    WideCharToMultiByte.c
+    WriteFile.c
+)
 
 list(APPEND PCH_SKIP_SOURCE
     testlist.c)
diff --git a/modules/rostests/apitests/kernel32/ReadFile.c b/modules/rostests/apitests/kernel32/ReadFile.c
new file mode 100644
index 00000000000..32aa2397a9a
--- /dev/null
+++ b/modules/rostests/apitests/kernel32/ReadFile.c
@@ -0,0 +1,223 @@
+/*
+ * PROJECT:     ReactOS API tests
+ * LICENSE:     MIT (https://spdx.org/licenses/MIT)
+ * PURPOSE:     Test for ReadFile
+ * COPYRIGHT:   Copyright 2026 Timo Kreuzer <timo.kreuzer@reactos.org>
+ */
+
+#include "precomp.h"
+
+static void Test_ReadFile_sync(HANDLE hFile)
+{
+    UCHAR Buffer[128];
+    DWORD dwBytesRead;
+    BOOL bResult;
+
+    SetFilePointer(hFile, 0, NULL, FILE_BEGIN);
+
+    /* Test NULL File */
+    SetLastError(0xdeadbeef);
+    dwBytesRead = 0xdeadbeef;
+    bResult = ReadFile(NULL, Buffer, sizeof(Buffer), &dwBytesRead, NULL);
+    ok_eq_bool(bResult, FALSE);
+    ok_eq_ulong(dwBytesRead, 0);
+    ok_eq_ulong(GetLastError(), ERROR_INVALID_HANDLE);
+
+    /* Test INVALID_HANDLE_VALUE */
+    SetLastError(0xdeadbeef);
+    dwBytesRead = 0xdeadbeef;
+    bResult = ReadFile(INVALID_HANDLE_VALUE, Buffer, sizeof(Buffer), &dwBytesRead, NULL);
+    ok_eq_bool(bResult, FALSE);
+    ok_eq_ulong(dwBytesRead, 0);
+    ok_eq_ulong(GetLastError(), ERROR_INVALID_HANDLE);
+
+    /* Read some bytes */
+    SetLastError(0xdeadbeef);
+    dwBytesRead = 0xdeadbeef;
+    bResult = ReadFile(hFile, Buffer, sizeof(Buffer), &dwBytesRead, NULL);
+    ok_eq_bool(bResult, TRUE);
+    ok_eq_ulong(dwBytesRead, sizeof(Buffer));
+    ok_eq_ulong(GetLastError(), 0xdeadbeef);
+
+    /* Try to read at end of file */
+    SetLastError(0xdeadbeef);
+    dwBytesRead = 0xdeadbeef;
+    ok(SetFilePointer(hFile, 0, NULL, FILE_END) > 0, "SetFilePointer failed\n");
+    bResult = ReadFile(hFile, Buffer, sizeof(Buffer), &dwBytesRead, NULL);
+    ok_eq_bool(bResult, TRUE);
+    ok_eq_ulong(dwBytesRead, 0);
+    ok_eq_ulong(GetLastError(), 0xdeadbeef);
+
+    /* Try to read 0 bytes at end of file */
+    SetLastError(0xdeadbeef);
+    bResult = ReadFile(hFile, Buffer, 0, &dwBytesRead, NULL);
+    ok_eq_bool(bResult, TRUE);
+    ok_eq_ulong(dwBytesRead, 0);
+    ok_eq_ulong(GetLastError(), 0xdeadbeef);
+    SetFilePointer(hFile, 0, NULL, FILE_BEGIN);
+
+    /* Test with NULL lpBuffer */
+    SetLastError(0xdeadbeef);
+    dwBytesRead = 0xdeadbeef;
+    StartSeh()
+        bResult = ReadFile(hFile, NULL, sizeof(Buffer), &dwBytesRead, NULL);
+        ok_eq_bool(bResult, FALSE);
+        ok_eq_ulong(dwBytesRead, 0);
+        ok_eq_ulong(GetLastError(), ERROR_NOACCESS);
+    EndSeh(STATUS_SUCCESS);
+
+    /* Test with NULL lpBuffer and 0 nNumberOfBytesToRead */
+    SetLastError(0xdeadbeef);
+    dwBytesRead = 0xdeadbeef;
+    StartSeh()
+        bResult = ReadFile(hFile, NULL, 0, &dwBytesRead, NULL);
+        ok_eq_bool(bResult, TRUE);
+        ok_eq_ulong(dwBytesRead, 0);
+        ok_eq_ulong(GetLastError(), 0xdeadbeef);
+    EndSeh(STATUS_SUCCESS);
+
+    /* Test with NULL lpNumberOfBytesRead */
+    SetLastError(0xdeadbeef);
+    StartSeh()
+        bResult = ReadFile(hFile, Buffer, sizeof(Buffer), NULL, NULL);
+        ok_eq_bool(bResult, TRUE);
+        ok_eq_ulong(GetLastError(), 0xdeadbeef);
+    EndSeh((GetNTVersion() >= _WIN32_WINNT_WIN8) ? STATUS_SUCCESS : EXCEPTION_ACCESS_VIOLATION);
+
+    /* Test with NULL lpNumberOfBytesRead at end of file */
+    ok(SetFilePointer(hFile, 0, NULL, FILE_END) > 0, "SetFilePointer failed\n");
+    SetLastError(0xdeadbeef);
+    StartSeh()
+        bResult = ReadFile(hFile, Buffer, sizeof(Buffer), NULL, NULL);
+        ok_eq_bool(bResult, TRUE);
+        ok_eq_ulong(GetLastError(), 0xdeadbeef);
+    EndSeh((GetNTVersion() >= _WIN32_WINNT_WIN8) ? STATUS_SUCCESS : EXCEPTION_ACCESS_VIOLATION);
+}
+
+static void Test_ReadFile_async(HANDLE hFile)
+{
+    BOOL bResult;
+    UCHAR Buffer[128];
+    DWORD dwBytesRead;
+    OVERLAPPED ol = { 0 };
+
+    SetFilePointer(hFile, 0, NULL, FILE_BEGIN);
+
+    /* Test NULL File */
+    SetLastError(0xdeadbeef);
+    dwBytesRead = 0xdeadbeef;
+    bResult = ReadFile(NULL, Buffer, sizeof(Buffer), &dwBytesRead, &ol);
+    ok_eq_bool(bResult, FALSE);
+    ok_eq_ulong(dwBytesRead, 0);
+    ok_eq_ulong(GetLastError(), ERROR_INVALID_HANDLE);
+
+    /* Test INVALID_HANDLE_VALUE */
+    SetLastError(0xdeadbeef);
+    dwBytesRead = 0xdeadbeef;
+    bResult = ReadFile(INVALID_HANDLE_VALUE, Buffer, sizeof(Buffer), &dwBytesRead, &ol);
+    ok_eq_bool(bResult, FALSE);
+    ok_eq_ulong(dwBytesRead, 0);
+    ok_eq_ulong(GetLastError(), ERROR_INVALID_HANDLE);
+
+    /* Read some bytes */
+    SetLastError(0xdeadbeef);
+    dwBytesRead = 0xdeadbeef;
+    bResult = ReadFile(hFile, Buffer, sizeof(Buffer), &dwBytesRead, &ol);
+    ok_eq_bool(bResult, TRUE);
+    dwBytesRead = 0xdeadbeef;
+    bResult = GetOverlappedResult(hFile, &ol, &dwBytesRead, TRUE);
+    ok_eq_bool(bResult, TRUE);
+    ok_eq_ulong(dwBytesRead, sizeof(Buffer));
+    ok_eq_ulong(GetLastError(), (GetNTVersion() >= _WIN32_WINNT_WIN10) ? 0 : 0xdeadbeef);
+
+    /* Try to read at end of file */
+    SetLastError(0xdeadbeef);
+    dwBytesRead = 0xdeadbeef;
+    ol.Offset = GetFileSize(hFile, NULL);
+    ok(ol.Offset > 0, "GetFileSize failed\n");
+    bResult = ReadFile(hFile, Buffer, sizeof(Buffer), &dwBytesRead, &ol);
+    ok_eq_bool(bResult, FALSE);
+    ok_eq_ulong(dwBytesRead, 0);
+    ok_eq_ulong(GetLastError(), ERROR_HANDLE_EOF);
+
+    /* Try to read 0 bytes at end of file */
+    SetLastError(0xdeadbeef);
+    bResult = ReadFile(hFile, Buffer, 0, &dwBytesRead, &ol);
+    ok_eq_bool(bResult, TRUE);
+    ok_eq_ulong(dwBytesRead, 0);
+    ok_eq_ulong(GetLastError(), 0xdeadbeef);
+    ol.Offset = 0;
+
+    /* Test with NULL lpBuffer */
+    SetLastError(0xdeadbeef);
+    dwBytesRead = 0xdeadbeef;
+    StartSeh()
+        bResult = ReadFile(hFile, NULL, sizeof(Buffer), &dwBytesRead, &ol);
+        ok_eq_bool(bResult, FALSE);
+        ok_eq_ulong(GetLastError(), ERROR_NOACCESS);
+    EndSeh(STATUS_SUCCESS);
+
+    /* Test with NULL lpBuffer and 0 nNumberOfBytesToRead */
+    SetLastError(0xdeadbeef);
+    dwBytesRead = 0xdeadbeef;
+    StartSeh()
+        bResult = ReadFile(hFile, NULL, 0, &dwBytesRead, &ol);
+        ok_eq_bool(bResult, TRUE);
+        ok_eq_ulong(GetLastError(), 0xdeadbeef);
+        bResult = GetOverlappedResult(hFile, &ol, &dwBytesRead, TRUE);
+        ok_eq_bool(bResult, TRUE);
+        ok_eq_ulong(dwBytesRead, 0);
+        ok_eq_ulong(GetLastError(), (GetNTVersion() >= _WIN32_WINNT_WIN10) ? 0 : 0xdeadbeef);
+    EndSeh(STATUS_SUCCESS);
+
+    /* Test with NULL lpNumberOfBytesRead */
+    SetLastError(0xdeadbeef);
+    bResult = ReadFile(hFile, Buffer, sizeof(Buffer), NULL, &ol);
+    ok_eq_bool(bResult, TRUE);
+    ok_eq_ulong(GetLastError(), 0xdeadbeef);
+    bResult = GetOverlappedResult(hFile, &ol, &dwBytesRead, TRUE);
+    ok_eq_bool(bResult, TRUE);
+    ok_eq_ulong(dwBytesRead, sizeof(Buffer));
+    ok_eq_ulong(GetLastError(), (GetNTVersion() >= _WIN32_WINNT_WIN10) ? 0 : 0xdeadbeef);
+
+    /* Test with NULL lpNumberOfBytesRead at end of file */
+    SetLastError(0xdeadbeef);
+    ol.Offset = GetFileSize(hFile, NULL);
+    ok(ol.Offset > 0, "GetFileSize failed\n");
+    bResult = ReadFile(hFile, Buffer, sizeof(Buffer), NULL, &ol);
+    ok_eq_bool(bResult, FALSE);
+    ok_eq_ulong(GetLastError(), ERROR_HANDLE_EOF);
+    SetLastError(0xdeadbeef);
+    dwBytesRead = 0xdeadbeef;
+    bResult = GetOverlappedResult(hFile, &ol, &dwBytesRead, TRUE);
+    ok_eq_bool(bResult, FALSE);
+    ok_eq_ulong(dwBytesRead, 0);
+    ok_eq_ulong(GetLastError(), ERROR_HANDLE_EOF);
+    ol.Offset = 0;
+}
+
+START_TEST(ReadFile)
+{
+    CHAR FileName[MAX_PATH];
+    HANDLE hFile;
+
+    /* Open the executable file */
+    GetModuleFileNameA(NULL, FileName, ARRAYSIZE(FileName));
+    hFile = CreateFileA(FileName,
+                        FILE_READ_ACCESS,
+                        FILE_SHARE_READ,
+                        NULL,
+                        OPEN_EXISTING,
+                        FILE_ATTRIBUTE_NORMAL,
+                        NULL);
+    if (hFile == INVALID_HANDLE_VALUE)
+    {
+        skip("CreateFileA failed with error %lu\n", GetLastError());
+        return;
+    }
+
+    Test_ReadFile_sync(hFile);
+    Test_ReadFile_async(hFile);
+
+    CloseHandle(hFile);
+}
diff --git a/modules/rostests/apitests/kernel32/WriteFile.c b/modules/rostests/apitests/kernel32/WriteFile.c
new file mode 100644
index 00000000000..05c9e1b4777
--- /dev/null
+++ b/modules/rostests/apitests/kernel32/WriteFile.c
@@ -0,0 +1,170 @@
+/*
+ * PROJECT:     ReactOS API tests
+ * LICENSE:     MIT (https://spdx.org/licenses/MIT)
+ * PURPOSE:     Test for WriteFile
+ * COPYRIGHT:   Copyright 2026 Timo Kreuzer <timo.kreuzer@reactos.org>
+ */
+
+#include "precomp.h"
+
+static void Test_WriteFile_sync(HANDLE hFile)
+{
+    UCHAR Buffer[128];
+    DWORD dwBytesWritten;
+    BOOL bResult;
+
+    SetFilePointer(hFile, 0, NULL, FILE_BEGIN);
+
+    /* Test NULL File */
+    SetLastError(0xdeadbeef);
+    dwBytesWritten = 0xdeadbeef;
+    bResult = WriteFile(NULL, Buffer, sizeof(Buffer), &dwBytesWritten, NULL);
+    ok_eq_bool(bResult, FALSE);
+    ok_eq_ulong(dwBytesWritten, 0);
+    ok_eq_ulong(GetLastError(), ERROR_INVALID_HANDLE);
+
+    /* Test INVALID_HANDLE_VALUE */
+    SetLastError(0xdeadbeef);
+    dwBytesWritten = 0xdeadbeef;
+    bResult = WriteFile(INVALID_HANDLE_VALUE, Buffer, sizeof(Buffer), &dwBytesWritten, NULL);
+    ok_eq_bool(bResult, FALSE);
+    ok_eq_ulong(dwBytesWritten, 0);
+    ok_eq_ulong(GetLastError(), ERROR_INVALID_HANDLE);
+
+    /* Write some bytes */
+    SetLastError(0xdeadbeef);
+    dwBytesWritten = 0xdeadbeef;
+    bResult = WriteFile(hFile, Buffer, sizeof(Buffer), &dwBytesWritten, NULL);
+    ok_eq_bool(bResult, TRUE);
+    ok_eq_ulong(dwBytesWritten, sizeof(Buffer));
+    ok_eq_ulong(GetLastError(), 0xdeadbeef);
+
+    /* Test with NULL lpBuffer */
+    SetLastError(0xdeadbeef);
+    dwBytesWritten = 0xdeadbeef;
+    StartSeh()
+        bResult = WriteFile(hFile, NULL, sizeof(Buffer), &dwBytesWritten, NULL);
+        ok_eq_bool(bResult, FALSE);
+        ok_eq_ulong(dwBytesWritten, 0);
+        ok_eq_ulong(GetLastError(), ERROR_INVALID_USER_BUFFER);
+    EndSeh(STATUS_SUCCESS);
+
+    /* Test with NULL lpBuffer and 0 nNumberOfBytesToWrite */
+    SetLastError(0xdeadbeef);
+    dwBytesWritten = 0xdeadbeef;
+    StartSeh()
+        bResult = WriteFile(hFile, NULL, 0, &dwBytesWritten, NULL);
+        ok_eq_bool(bResult, TRUE);
+        ok_eq_ulong(dwBytesWritten, 0);
+        ok_eq_ulong(GetLastError(), 0xdeadbeef);
+    EndSeh(STATUS_SUCCESS);
+
+    /* Test with NULL lpNumberOfBytesWritten */
+    SetLastError(0xdeadbeef);
+    StartSeh()
+        bResult = WriteFile(hFile, Buffer, sizeof(Buffer), NULL, NULL);
+        ok_eq_bool(bResult, TRUE);
+        ok_eq_ulong(GetLastError(), 0xdeadbeef);
+    EndSeh((GetNTVersion() >= _WIN32_WINNT_WIN8) ? STATUS_SUCCESS : EXCEPTION_ACCESS_VIOLATION);
+}
+
+static void Test_WriteFile_async(HANDLE hFile)
+{
+    BOOL bResult;
+    UCHAR Buffer[128];
+    DWORD dwBytesWritten;
+    OVERLAPPED ol = { 0 };
+
+    SetFilePointer(hFile, 0, NULL, FILE_BEGIN);
+
+    /* Test NULL File */
+    SetLastError(0xdeadbeef);
+    dwBytesWritten = 0xdeadbeef;
+    bResult = WriteFile(NULL, Buffer, sizeof(Buffer), &dwBytesWritten, &ol);
+    ok_eq_bool(bResult, FALSE);
+    ok_eq_ulong(dwBytesWritten, 0);
+    ok_eq_ulong(GetLastError(), ERROR_INVALID_HANDLE);
+
+    /* Test INVALID_HANDLE_VALUE */
+    SetLastError(0xdeadbeef);
+    dwBytesWritten = 0xdeadbeef;
+    bResult = WriteFile(INVALID_HANDLE_VALUE, Buffer, sizeof(Buffer), &dwBytesWritten, &ol);
+    ok_eq_bool(bResult, FALSE);
+    ok_eq_ulong(dwBytesWritten, 0);
+    ok_eq_ulong(GetLastError(), ERROR_INVALID_HANDLE);
+
+    /* Write some bytes */
+    SetLastError(0xdeadbeef);
+    dwBytesWritten = 0xdeadbeef;
+    bResult = WriteFile(hFile, Buffer, sizeof(Buffer), &dwBytesWritten, &ol);
+    ok_eq_bool(bResult, TRUE);
+    dwBytesWritten = 0xdeadbeef;
+    bResult = GetOverlappedResult(hFile, &ol, &dwBytesWritten, TRUE);
+    ok_eq_bool(bResult, TRUE);
+    ok_eq_ulong(dwBytesWritten, sizeof(Buffer));
+    ok_eq_ulong(GetLastError(), (GetNTVersion() >= _WIN32_WINNT_WIN10) ? 0 : 0xdeadbeef);
+
+    /* Test with NULL lpBuffer */
+    SetLastError(0xdeadbeef);
+    dwBytesWritten = 0xdeadbeef;
+    StartSeh()
+        bResult = WriteFile(hFile, NULL, sizeof(Buffer), &dwBytesWritten, &ol);
+        ok_eq_bool(bResult, FALSE);
+        ok_eq_ulong(GetLastError(), ERROR_INVALID_USER_BUFFER);
+    EndSeh(STATUS_SUCCESS);
+
+    /* Test with NULL lpBuffer and 0 nNumberOfBytesToWrite */
+    SetLastError(0xdeadbeef);
+    dwBytesWritten = 0xdeadbeef;
+    StartSeh()
+        bResult = WriteFile(hFile, NULL, 0, &dwBytesWritten, &ol);
+        ok_eq_bool(bResult, TRUE);
+        ok_eq_ulong(GetLastError(), 0xdeadbeef);
+        bResult = GetOverlappedResult(hFile, &ol, &dwBytesWritten, TRUE);
+        ok_eq_bool(bResult, TRUE);
+        ok_eq_ulong(dwBytesWritten, 0);
+        ok_eq_ulong(GetLastError(), (GetNTVersion() >= _WIN32_WINNT_WIN10) ? 0 : 0xdeadbeef);
+    EndSeh(STATUS_SUCCESS);
+
+    /* Test with NULL lpNumberOfBytesWritten */
+    SetLastError(0xdeadbeef);
+    bResult = WriteFile(hFile, Buffer, sizeof(Buffer), NULL, &ol);
+    ok_eq_bool(bResult, TRUE);
+    ok_eq_ulong(GetLastError(), 0xdeadbeef);
+    bResult = GetOverlappedResult(hFile, &ol, &dwBytesWritten, TRUE);
+    ok_eq_bool(bResult, TRUE);
+    ok_eq_ulong(dwBytesWritten, sizeof(Buffer));
+    ok_eq_ulong(GetLastError(), (GetNTVersion() >= _WIN32_WINNT_WIN10) ? 0 : 0xdeadbeef);
+}
+
+START_TEST(WriteFile)
+{
+    HANDLE hFile;
+
+    /* Create a temp file name */
+    CHAR tempFileName[MAX_PATH];
+    if (!GetTempFileNameA(".", "writetest", 0, tempFileName))
+    {
+        skip("GetTempFileNameA failed with error %lu\n", GetLastError());
+        return;
+    }
+
+    /* Create a temp file to write to */
+    hFile = CreateFileA(tempFileName,
+                        GENERIC_WRITE,
+                        0,
+                        NULL,
+                        CREATE_ALWAYS,
+                        FILE_ATTRIBUTE_NORMAL | FILE_FLAG_DELETE_ON_CLOSE,
+                        NULL);
+    if (hFile == INVALID_HANDLE_VALUE)
+    {
+        skip("CreateFileA failed with error %lu\n", GetLastError());
+        return;
+    }
+
+    Test_WriteFile_sync(hFile);
+    Test_WriteFile_async(hFile);
+
+    CloseHandle(hFile);
+}