8.5" wide is the largest you can print.

Thank you.

Is there an extra tray for this machine that would hold 11 X 15" paper?

Unfortunatly none of Dell's laser printers are capable of wide format printing. That is an expensive option. Everything in the machine has to be bigger to handle it; the whole paper handling path, the drum, fusers, etc. Search for "large format laser printer" on Google. Looks like they start at about $1,600.00 and go up fast.

Thanks for your help.  I think I will stick with regular size paper.......