myDATA guides
Practical guides to expense classification, based on AADE’s official documentation.
Greek e-invoicing 2026–2027: the new timeline
The new timeline for businesses with turnover up to €1M: 2 Nov 2026, 31 Jan 2027 and 1 Feb 2027.
myDATA E3 codes and expense classification categories
Expense categories, E3 codes and VAT classifications, with the allowed combinations.
myDATA expense classification errors: 306, 307, 313 and the rest
What errors 306, 307, 313 and the other classification errors mean, and how to fix them.