Unique Document Identification Number (UDIN) is an 18-Digits system generated unique number for every document certified/attested by Practising Chartered Accountants. The Institute of Chartered Accountants (ICAI) has mandated the full-time practising Chartered Accountants (CA) to generate UDIN for each assignment. Here we see the UDIN for the Goods and Services Tax (GST) and Tax Audit….