As per provisions of Rule 18 of the CGST Rules and corresponding State / Union Territory Rules, the taxpayer has to display his certificate of registration and registration number at a prominent location at the principal place of business and at every additional place of business.
As per provisions of Section 125 of the CGST Act, if the taxpayer does not display, a penalty Upto Rs 25,000 can be levied. If the penalty of Rs 15,000 is levied under central tax as a penalty then under state tax also an equivalent amount of penalty will be levied.
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