Format of a GST Number (GSTIN)

Registration IDs Digits
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15
Normal, Composite, Casual State (SS) 10 Digit PAN Number (1-9)
(Z, 1-9, A,B,E-J) Check Digit
Input Service Distributor State (SS) 10 Digit PAN Number (1-9)
S Check Digit
Tax Collector State (SS) 10 Digit PAN Number (1-9)
C Check Digit
Tax Deductor State (SS) 10 Digit PAN Number (1-9)
D Check Digit
Nonresident Foreign Taxpayers (NRI) State (SS) Year (YY) Country (CCC) 00000 N F T
UN Bodies, Embassies, etc. State (SS) Year (YY) Country (CCC) 00000 U N Check Digit
Other Notified Persons State (SS) Year (YY) Country (CCC) 00000 O N P
Tax Return Preparer State (SS) Year (YY) 00000000 T R P
Temporary ID State (SS) Year (YY) 00000000 T M P
State (SS) 2 Digit State Code
Year (YY) The last 2 Digit Year (example: 17, for 2017)
Country (CCC) 3 Digit Country Code
00000 5 digit serial number per year
00000000 8 digit serial number irrespective of year

To know about GSTIN, please visit the article What is GSTIN?.

Use this tool to check the format of multiple GSTIN/UIN numbers - GSTIN Validator Tool Help video