Commencement of State GST Act allows staged activation of provisions by official notification, enabling different provisions to commence separately. The Bihar Goods and Services Tax Act, 2017 establishes the statutory basis for levy and collection of tax on intra State supply of goods or services, names the Act, and extends it to the whole State of Bihar. Commencement is by notification in the Official Gazette issued by the State Government; different provisions may be brought into force on different dates and references to commencement are to be read as the coming into force of the specific provision.