03 November 2017
13th character would be a number or letter?, today i seen one gstin number that includes 13th character as a letter in gstn.gov.in site,,, when its changed??
04 November 2017
2. Structure of GSTIN
Each taxpayer is assigned a state-wise PAN-based 15-digit Goods and Services Taxpayer Identification Number (GSTIN).

Here is a format break-down of the GSTIN:
The first two digits represent the state code as per Indian Census 2011. Every state has a unique code. For instance,State code of Karnataka is 29State code of Delhi is 07The next ten digits will be the PAN number of the taxpayerThe thirteenth digit will be assigned based on the number of registration within a stateThe fourteenth digit will be Z by defaultThe last digit will be for check code. It may be an alphabet or a number.
(source: Clear tax)
04 November 2017
Subject to the provisions of sub-section (12) of section 25, where the application for grant of registration has been approved under rule 2, a certificate of registration in FORM GST REG-06 showing the principal place of business and additional place(s) of business shall be made available to the applicant on the Common Portal and a Goods and Services Tax Identification Number (hereinafter in these rules referred to as “GSTIN”) shall be assigned in the following format: (a) two characters for the State code; (b) ten characters for the PAN or the Tax Deduction and Collection Account Number; (c) two characters for the entity code; and (d) one checksum character.