Thanks for the suggestions everyone. There's at least three that are coming up with multiple votes so I'll give them all a run-through and see which one "fits" best.
That's what I use for FREE now and it does the job very well. I did used to use SmartFTP, that I purchased and was much better. But wasn't aware at first you had to renew the software again each year, when one day it stopped working and showed a nag message asking to pay to keep on using it!