Treatment is same for registered, unregistered, composition dealers.
These are the Rules regarding the format of Credit Note:-
A revised tax invoice referred to in section 31 and credit or debit notes referred to in section 34 shall contain the following particulars, namely:-
[a] the word "Revised Invoice", wherever applicable, indicated prominently;
[b] name, address and Goods and Services Tax Identification Number of the supplier;
[c] nature of the document;
[d] a consecutive serial number not exceeding sixteen characters, in one or multiple series, containing alphabets or numerals or special characters-hyphen or dash and slash symbolised as "-" and "/" respectively, and any combination thereof, unique for a financial year;
[e] date of issue of the document;
[f] name, address and Goods and Services Tax Identification Number or Unique Identity Number, if registered, of the recipient;
[g] name and address of the recipient and the address of delivery, along with the name of State and its code, if such recipient is un-registered;
[h] serial number and date of the corresponding tax invoice or, as the case may be, bill of supply;
[i] value of taxable supply of goods or services, rate of tax and the amount of the tax credited or, as the case may be, debited to the recipient; and
[j] signature or digital signature of the supplier or his authorised representative.