diff --git a/include/zephyr/posix/unistd.h b/include/zephyr/posix/unistd.h
index 0865a8e131c..d5782200275 100644
--- a/include/zephyr/posix/unistd.h
+++ b/include/zephyr/posix/unistd.h
@@ -237,6 +237,7 @@ int close(int file);
 ssize_t write(int file, const void *buffer, size_t count);
 ssize_t read(int file, void *buffer, size_t count);
 off_t lseek(int file, off_t offset, int whence);
+int fsync(int fd);
 
 /* File System related operations */
 int rename(const char *old, const char *newp);
diff --git a/lib/os/fdtable.c b/lib/os/fdtable.c
index 757ebf4361f..1fd42ad1208 100644
--- a/lib/os/fdtable.c
+++ b/lib/os/fdtable.c
@@ -362,6 +362,7 @@ int fsync(int fd)
 
 	return z_fdtable_call_ioctl(fdtable[fd].vtable, fdtable[fd].obj, ZFD_IOCTL_FSYNC);
 }
+FUNC_ALIAS(fsync, _fsync, int);
 
 off_t lseek(int fd, off_t offset, int whence)
 {
diff --git a/lib/posix/options/fs.c b/lib/posix/options/fs.c
index ca861a729b1..d7203d150e9 100644
--- a/lib/posix/options/fs.c
+++ b/lib/posix/options/fs.c
@@ -144,6 +144,10 @@ static int fs_ioctl_vmeth(void *obj, unsigned int request, va_list args)
 	struct posix_fs_desc *ptr = obj;
 
 	switch (request) {
+	case ZFD_IOCTL_FSYNC: {
+		rc = fs_sync(&ptr->file);
+		break;
+	}
 	case ZFD_IOCTL_LSEEK: {
 		off_t offset;
 		int whence;