In or On

Ship, the answer might get involved if not controversial. I presume by "enclosure" you must mean for instance a separate sheet or booklet contained, eg, in a pocket, in which case "on" would seem to fit better if that's where you actually enter the data

.....which might become obvious upon accessing the enclosure itself in which case the very wording of your lead-in suggests, "…..enter your information using the enclosure," or if more than one, eg, "…the enclosure contained in the pocket labeled 'Data Entry' "

…while "enter the data in the enclosure" seems to imply that the enclosure contains or will contain some sort of data that you're instructed to enter somewhere else not specified


For my sidewise approach to q's of this sort I am regularly attacked by other a2k participants more attuned to the more direct approach; and so I queried my Better Half, who is much smarter than I, and in this case at least, she agreed; so I am confident you might find it useful after all

In my work, we write and work with complex technical procedures, sometimes hundreds of pages long. These procedures sometimes contain data tables, forms, and other related documents that we include at the end of the procedure and identify as "Enclosures". Everything is on printed paper. My question is, when directing data or other information be entered in(on) the Enclosure in question, is the verbage "in" or "on".

As I hope I had conveyed above, Ship, I'd use "on," because "in" carries an implication that the enclosures already contain some sort of data you're supposed to enter, or transfer, to some other unspecified destination

Help Con, where are you

on a line, in an enclosure.