You can configure CuteFTP to keep a thread open for a specific number of seconds after a transfer is complete. Leaving data connections open allows more transfers to use the same connection, avoiding the need to open new connections.
To specify the wait time that CuteFTP
On the main menu, click Tools > Global Options (or press ALT+F7).
Expand the Transfer node, then click Events. The Events options appear.
In the Close the file transfer thread n seconds after the transfer is finished box, specify the time that CuteFTP will wait to close the data connection after a transfer is complete. Specify a time between 0 and 1,000 seconds.
Click Apply if you are going to make changes to other pages; click OK to save changes and close the Global Options dialog box.