Have a Brother HL-L2340DW printer. I never thought about which side it prints on or have forgotten. But I tried printing the back side of a used sheet and found that it prints on the BOTTOM facing-down side of the paper. I had assumed it would print on the top side. It made me wonder if I should have placed the blank supply paper from package top side down and did not believe I had so I reversed it. I do not know if it matters but I always thought it printed on the top side or else did not think about it at all. But I did flip the paper over that was in the drawer. I think I had read to print on the top side of the paper as it comes from the package. Actually, since it makes one-sided or two-sided copies I guess maybe it does not matter and I have done both without noticing any adversities. But I though I read somewhere to print on top side preferably even if either worked. If it is supposed to print the top side first though I would like to do it that way. Like to be correct.