Have you looked around at the various settings in the Photoshop Print Settings preview dialog you get on the way to printing your file to the printer?
There's a whole Position and Size section there on sizing your print. Make the dialog bigger or scroll the right side if you're not seeing it.
You've missed something in your printer vendor specific driver settings, or a bug in your printer driver code.
Also, you haven't told us what printer, what OS, or anything that would help us help you.
Thanks for your replies guys,
The printer in an Epson Stylus Office T1100. But im not sure this will matter because it is doing the same thing when I print it to another machine.
Thanks Noel, i will try this out.