diff --git a/backend/smb/filepool.go b/backend/smb/filepool.go
new file mode 100644
index 000000000..0061ec1ff
--- /dev/null
+++ b/backend/smb/filepool.go
@@ -0,0 +1,99 @@
+package smb
+
+import (
+	"context"
+	"fmt"
+	"os"
+	"sync"
+
+	"github.com/cloudsoda/go-smb2"
+	"golang.org/x/sync/errgroup"
+)
+
+// FsInterface defines the methods that filePool needs from Fs
+type FsInterface interface {
+	getConnection(ctx context.Context, share string) (*conn, error)
+	putConnection(pc **conn, err error)
+	removeSession()
+}
+
+type file struct {
+	*smb2.File
+	c *conn
+}
+
+type filePool struct {
+	ctx   context.Context
+	fs    FsInterface
+	share string
+	path  string
+
+	mu   sync.Mutex
+	pool []*file
+}
+
+func newFilePool(ctx context.Context, fs FsInterface, share, path string) *filePool {
+	return &filePool{
+		ctx:   ctx,
+		fs:    fs,
+		share: share,
+		path:  path,
+	}
+}
+
+func (p *filePool) get() (*file, error) {
+	p.mu.Lock()
+	if len(p.pool) > 0 {
+		f := p.pool[len(p.pool)-1]
+		p.pool = p.pool[:len(p.pool)-1]
+		p.mu.Unlock()
+		return f, nil
+	}
+	p.mu.Unlock()
+
+	c, err := p.fs.getConnection(p.ctx, p.share)
+	if err != nil {
+		return nil, err
+	}
+
+	fl, err := c.smbShare.OpenFile(p.path, os.O_WRONLY, 0o644)
+	if err != nil {
+		p.fs.putConnection(&c, err)
+		return nil, fmt.Errorf("failed to open: %w", err)
+	}
+
+	return &file{File: fl, c: c}, nil
+}
+
+func (p *filePool) put(f *file, err error) {
+	if f == nil {
+		return
+	}
+
+	if err != nil {
+		_ = f.Close()
+		p.fs.putConnection(&f.c, err)
+		return
+	}
+
+	p.mu.Lock()
+	p.pool = append(p.pool, f)
+	p.mu.Unlock()
+}
+
+func (p *filePool) drain() error {
+	p.mu.Lock()
+	files := p.pool
+	p.pool = nil
+	p.mu.Unlock()
+
+	g, _ := errgroup.WithContext(p.ctx)
+	for _, f := range files {
+		g.Go(func() error {
+			err := f.Close()
+			p.fs.putConnection(&f.c, err)
+			return err
+		})
+	}
+	return g.Wait()
+}
diff --git a/backend/smb/filepool_test.go b/backend/smb/filepool_test.go
new file mode 100644
index 000000000..7cf90988b
--- /dev/null
+++ b/backend/smb/filepool_test.go
@@ -0,0 +1,228 @@
+package smb
+
+import (
+	"context"
+	"errors"
+	"sync"
+	"testing"
+
+	"github.com/cloudsoda/go-smb2"
+	"github.com/stretchr/testify/assert"
+)
+
+// Mock Fs that implements FsInterface
+type mockFs struct {
+	mu                  sync.Mutex
+	putConnectionCalled bool
+	putConnectionErr    error
+	getConnectionCalled bool
+	getConnectionErr    error
+	getConnectionResult *conn
+	removeSessionCalled bool
+}
+
+func (m *mockFs) putConnection(pc **conn, err error) {
+	m.mu.Lock()
+	defer m.mu.Unlock()
+	m.putConnectionCalled = true
+	m.putConnectionErr = err
+}
+
+func (m *mockFs) getConnection(ctx context.Context, share string) (*conn, error) {
+	m.mu.Lock()
+	defer m.mu.Unlock()
+	m.getConnectionCalled = true
+	if m.getConnectionErr != nil {
+		return nil, m.getConnectionErr
+	}
+	if m.getConnectionResult != nil {
+		return m.getConnectionResult, nil
+	}
+	return &conn{}, nil
+}
+
+func (m *mockFs) removeSession() {
+	m.mu.Lock()
+	defer m.mu.Unlock()
+	m.removeSessionCalled = true
+}
+
+func (m *mockFs) isPutConnectionCalled() bool {
+	m.mu.Lock()
+	defer m.mu.Unlock()
+	return m.putConnectionCalled
+}
+
+func (m *mockFs) getPutConnectionErr() error {
+	m.mu.Lock()
+	defer m.mu.Unlock()
+	return m.putConnectionErr
+}
+
+func (m *mockFs) isGetConnectionCalled() bool {
+	m.mu.Lock()
+	defer m.mu.Unlock()
+	return m.getConnectionCalled
+}
+
+func newMockFs() *mockFs {
+	return &mockFs{}
+}
+
+// Helper function to create a mock file
+func newMockFile() *file {
+	return &file{
+		File: &smb2.File{},
+		c:    &conn{},
+	}
+}
+
+// Test filePool creation
+func TestNewFilePool(t *testing.T) {
+	ctx := context.Background()
+	fs := newMockFs()
+	share := "testshare"
+	path := "/test/path"
+
+	pool := newFilePool(ctx, fs, share, path)
+
+	assert.NotNil(t, pool)
+	assert.Equal(t, ctx, pool.ctx)
+	assert.Equal(t, fs, pool.fs)
+	assert.Equal(t, share, pool.share)
+	assert.Equal(t, path, pool.path)
+	assert.Empty(t, pool.pool)
+}
+
+// Test getting file from pool when pool has files
+func TestFilePool_Get_FromPool(t *testing.T) {
+	ctx := context.Background()
+	fs := newMockFs()
+	pool := newFilePool(ctx, fs, "testshare", "/test/path")
+
+	// Add a mock file to the pool
+	mockFile := newMockFile()
+	pool.pool = append(pool.pool, mockFile)
+
+	// Get file from pool
+	f, err := pool.get()
+
+	assert.NoError(t, err)
+	assert.NotNil(t, f)
+	assert.Equal(t, mockFile, f)
+	assert.Empty(t, pool.pool)
+}
+
+// Test getting file when pool is empty
+func TestFilePool_Get_EmptyPool(t *testing.T) {
+	ctx := context.Background()
+	fs := newMockFs()
+
+	// Set up the mock to return an error from getConnection
+	// This tests that the pool calls getConnection when empty
+	fs.getConnectionErr = errors.New("connection failed")
+
+	pool := newFilePool(ctx, fs, "testshare", "test/path")
+
+	// This should call getConnection and return the error
+	f, err := pool.get()
+	assert.Error(t, err)
+	assert.Nil(t, f)
+	assert.True(t, fs.isGetConnectionCalled())
+	assert.Equal(t, "connection failed", err.Error())
+}
+
+// Test putting file successfully
+func TestFilePool_Put_Success(t *testing.T) {
+	ctx := context.Background()
+	fs := newMockFs()
+	pool := newFilePool(ctx, fs, "testshare", "/test/path")
+
+	mockFile := newMockFile()
+
+	pool.put(mockFile, nil)
+
+	assert.Len(t, pool.pool, 1)
+	assert.Equal(t, mockFile, pool.pool[0])
+}
+
+// Test putting file with error
+func TestFilePool_Put_WithError(t *testing.T) {
+	ctx := context.Background()
+	fs := newMockFs()
+	pool := newFilePool(ctx, fs, "testshare", "/test/path")
+
+	mockFile := newMockFile()
+
+	pool.put(mockFile, errors.New("write error"))
+
+	// Should call putConnection with error
+	assert.True(t, fs.isPutConnectionCalled())
+	assert.Equal(t, errors.New("write error"), fs.getPutConnectionErr())
+	assert.Empty(t, pool.pool)
+}
+
+// Test putting nil file
+func TestFilePool_Put_NilFile(t *testing.T) {
+	ctx := context.Background()
+	fs := newMockFs()
+	pool := newFilePool(ctx, fs, "testshare", "/test/path")
+
+	// Should not panic
+	pool.put(nil, nil)
+	pool.put(nil, errors.New("some error"))
+
+	assert.Empty(t, pool.pool)
+}
+
+// Test draining pool with files
+func TestFilePool_Drain_WithFiles(t *testing.T) {
+	ctx := context.Background()
+	fs := newMockFs()
+	pool := newFilePool(ctx, fs, "testshare", "/test/path")
+
+	// Add mock files to pool
+	mockFile1 := newMockFile()
+	mockFile2 := newMockFile()
+	pool.pool = append(pool.pool, mockFile1, mockFile2)
+
+	// Before draining
+	assert.Len(t, pool.pool, 2)
+
+	_ = pool.drain()
+	assert.Empty(t, pool.pool)
+}
+
+// Test concurrent access to pool
+func TestFilePool_ConcurrentAccess(t *testing.T) {
+	ctx := context.Background()
+	fs := newMockFs()
+	pool := newFilePool(ctx, fs, "testshare", "/test/path")
+
+	const numGoroutines = 10
+	for i := 0; i < numGoroutines; i++ {
+		mockFile := newMockFile()
+		pool.pool = append(pool.pool, mockFile)
+	}
+
+	// Test concurrent get operations
+	done := make(chan bool, numGoroutines)
+
+	for i := 0; i < numGoroutines; i++ {
+		go func() {
+			defer func() { done <- true }()
+
+			f, err := pool.get()
+			if err == nil {
+				pool.put(f, nil)
+			}
+		}()
+	}
+
+	for i := 0; i < numGoroutines; i++ {
+		<-done
+	}
+
+	// Pool should be in a consistent after the concurrence access
+	assert.Len(t, pool.pool, numGoroutines)
+}
diff --git a/backend/smb/smb.go b/backend/smb/smb.go
index d102233f5..993b2ec7d 100644
--- a/backend/smb/smb.go
+++ b/backend/smb/smb.go
@@ -3,6 +3,7 @@ package smb
 
 import (
 	"context"
+	"errors"
 	"fmt"
 	"io"
 	"os"
@@ -503,13 +504,73 @@ func (f *Fs) About(ctx context.Context) (_ *fs.Usage, err error) {
 	return usage, nil
 }
 
+type smbWriterAt struct {
+	pool    *filePool
+	closed  bool
+	closeMu sync.Mutex
+	wg      sync.WaitGroup
+}
+
+func (w *smbWriterAt) WriteAt(p []byte, off int64) (int, error) {
+	w.closeMu.Lock()
+	if w.closed {
+		w.closeMu.Unlock()
+		return 0, errors.New("writer already closed")
+	}
+	w.wg.Add(1)
+	w.closeMu.Unlock()
+	defer w.wg.Done()
+
+	f, err := w.pool.get()
+	if err != nil {
+		return 0, fmt.Errorf("failed to get file from pool: %w", err)
+	}
+
+	n, writeErr := f.WriteAt(p, off)
+	w.pool.put(f, writeErr)
+
+	if writeErr != nil {
+		return n, fmt.Errorf("failed to write at offset %d: %w", off, writeErr)
+	}
+
+	return n, writeErr
+}
+
+func (w *smbWriterAt) Close() error {
+	w.closeMu.Lock()
+	defer w.closeMu.Unlock()
+
+	if w.closed {
+		return nil
+	}
+	w.closed = true
+
+	// Wait for all pending writes to finish
+	w.wg.Wait()
+
+	var errs []error
+
+	// Drain the pool
+	if err := w.pool.drain(); err != nil {
+		errs = append(errs, fmt.Errorf("failed to drain file pool: %w", err))
+	}
+
+	// Remove session
+	w.pool.fs.removeSession()
+
+	if len(errs) > 0 {
+		return errors.Join(errs...)
+	}
+
+	return nil
+}
+
 // OpenWriterAt opens with a handle for random access writes
 //
 // Pass in the remote desired and the size if known.
 //
 // It truncates any existing object
 func (f *Fs) OpenWriterAt(ctx context.Context, remote string, size int64) (fs.WriterAtCloser, error) {
-	var err error
 	o := &Object{
 		fs:     f,
 		remote: remote,
@@ -519,27 +580,42 @@ func (f *Fs) OpenWriterAt(ctx context.Context, remote string, size int64) (fs.Wr
 		return nil, fs.ErrorIsDir
 	}
 
-	err = o.fs.ensureDirectory(ctx, share, filename)
+	err := o.fs.ensureDirectory(ctx, share, filename)
 	if err != nil {
 		return nil, fmt.Errorf("failed to make parent directories: %w", err)
 	}
 
-	filename = o.fs.toSambaPath(filename)
-
-	o.fs.addSession() // Show session in use
-	defer o.fs.removeSession()
+	smbPath := o.fs.toSambaPath(filename)
 
+	// One-time truncate
 	cn, err := o.fs.getConnection(ctx, share)
 	if err != nil {
 		return nil, err
 	}
-
-	fl, err := cn.smbShare.OpenFile(filename, os.O_WRONLY|os.O_CREATE|os.O_TRUNC, 0o644)
+	file, err := cn.smbShare.OpenFile(smbPath, os.O_CREATE|os.O_WRONLY|os.O_TRUNC, 0o644)
 	if err != nil {
-		return nil, fmt.Errorf("failed to open: %w", err)
+		o.fs.putConnection(&cn, err)
+		return nil, err
 	}
+	if size > 0 {
+		if truncateErr := file.Truncate(size); truncateErr != nil {
+			_ = file.Close()
+			o.fs.putConnection(&cn, truncateErr)
+			return nil, fmt.Errorf("failed to truncate file: %w", truncateErr)
+		}
+	}
+	if closeErr := file.Close(); closeErr != nil {
+		o.fs.putConnection(&cn, closeErr)
+		return nil, fmt.Errorf("failed to close file after truncate: %w", closeErr)
+	}
+	o.fs.putConnection(&cn, nil)
 
-	return fl, nil
+	// Add a new session
+	o.fs.addSession()
+
+	return &smbWriterAt{
+		pool: newFilePool(ctx, o.fs, share, smbPath),
+	}, nil
 }
 
 // Shutdown the backend, closing any background tasks and any