Tax Office Reference Number?

I need to get my tax office reference number for my back home tax office but can't find one on any documents/tax returns I have. Is there a special number or do they use the My Number?

is better to ask tax office ...

Chike

Well, let's assume I could guess that but came here for an actual answer.....

If they are looking for an ID number, then the "My Number" is your ID. That will be consistent from one year to another.

I checked my tax return papers (I do "kakutei shinkoku"), there is a number used by the local tax office printed on that form - an 8-digit number below the box where your name/address go in. I've been living at the same address (meaning filing with the same local tax office) for some years, and this number is also consistent from one year to the next. On that form, they called it simply "bango" (number) one year, and "seiri bango" (something like filing number) in another, but the number remains the same.