As per Sec 25(4) of CGST Act, 2017 every branch/office of a company/entity having separate GSTIN belonging to one legal entity (single PAN) is a distinct person, whether located in the same state or different states. So, supply of goods or services between these branches are covered within the meaning & scope of supply U/s 7(1) . Further, as per Para 2 of Schedule I of CGST Act, even if consideration is not involved, supply of goods or services or both between related persons or between distinct persons as specified in section 25, when made in the course or furtherance of business is taxable under GST, if the said supply is otherwise not exempted.