Outbound network traffic originating from a client is filtered, to check for files targeted for upload to remote sites. When a file targeted for upload to a remote site is detected, a remote storage location at which the client's backup data is stored is checked for a copy of the detected file. If a copy of the file is located at the remote backup site, that copy is substituted for the client copy in the network transmission to the target remote site. By uploading online copies of files when available, the client upload experience is much faster, and local bandwidth is preserved for other tasks.