rsync -azP -e "ssh -p PORT" SOURCEFILE USER@HOST:DESTINATION
Replace PORT with the port number, SOURCEFILE with the name of the file, HOST with the ip or hostname of the receiving host, and DESTINATION with the directory on the receiving host.
The 'a' option is a shortcut to standard options, including preserving file permissions and links.
The 'z' option is for using compression.
The 'P' option allows seeing progress on the transfer.
The 'e' option allows for setting special ssh parameters, including using a non-standard port.