I'm doing supply at the moment and my agency urged me to join this company to deal with my tax. I can claim expenses to offset my tax and increase my pay or so I was told. I have had a few payslips through and if was not for my supply agencies guarantee to may me better off I would have lost money being with them. It seems that I make no money out of claiming the expenses but key take a nice £22 pound fee a week. It seems pointless joining all you seem to be doing is make this company some money not yourself I think I'd rather pay it in tax. Also is it normal to be paying your agency's Ni contributions as I seem to be pay may own and some for them.