diff --git a/backend/box/upload.go b/backend/box/upload.go
index 49771978d..63892ec14 100644
--- a/backend/box/upload.go
+++ b/backend/box/upload.go
@@ -16,6 +16,7 @@ import (
 
 	"github.com/ncw/rclone/backend/box/api"
 	"github.com/ncw/rclone/fs"
+	"github.com/ncw/rclone/fs/accounting"
 	"github.com/ncw/rclone/lib/rest"
 	"github.com/pkg/errors"
 )
@@ -52,9 +53,8 @@ func sha1Digest(digest []byte) string {
 }
 
 // uploadPart uploads a part in an upload session
-func (o *Object) uploadPart(SessionID string, offset, totalSize int64, chunk []byte) (response *api.UploadPartResponse, err error) {
+func (o *Object) uploadPart(SessionID string, offset, totalSize int64, chunk []byte, wrap accounting.WrapFn) (response *api.UploadPartResponse, err error) {
 	chunkSize := int64(len(chunk))
-	in := bytes.NewReader(chunk)
 	sha1sum := sha1.Sum(chunk)
 	opts := rest.Opts{
 		Method:        "PUT",
@@ -66,11 +66,10 @@ func (o *Object) uploadPart(SessionID string, offset, totalSize int64, chunk []b
 		ExtraHeaders: map[string]string{
 			"Digest": sha1Digest(sha1sum[:]),
 		},
-		Body: in,
 	}
 	var resp *http.Response
 	err = o.fs.pacer.Call(func() (bool, error) {
-		_, _ = in.Seek(0, 0)
+		opts.Body = wrap(bytes.NewReader(chunk))
 		resp, err = o.fs.srv.CallJSON(&opts, nil, &response)
 		return shouldRetry(resp, err)
 	})
@@ -189,6 +188,10 @@ func (o *Object) uploadMultipart(in io.Reader, leaf, directoryID string, size in
 		}
 	}()
 
+	// unwrap the accounting from the input, we use wrap to put it
+	// back on after the buffering
+	in, wrap := accounting.UnWrap(in)
+
 	// Upload the chunks
 	remaining := size
 	position := int64(0)
@@ -230,7 +233,7 @@ outer:
 			defer wg.Done()
 			defer o.fs.uploadToken.Put()
 			fs.Debugf(o, "Uploading part %d/%d offset %v/%v part size %v", part+1, session.TotalParts, fs.SizeSuffix(position), fs.SizeSuffix(size), fs.SizeSuffix(chunkSize))
-			partResponse, err := o.uploadPart(session.ID, position, size, buf)
+			partResponse, err := o.uploadPart(session.ID, position, size, buf, wrap)
 			if err != nil {
 				err = errors.Wrap(err, "multipart upload failed to upload part")
 				select {