Harmonized System of Nomenclature (HSN) is an internationally recognized product/items coding system which is also has been accepted in India. It contains almost 5000 commodity groups which is being identified by a six digit code. Each group is assigned in a most scientific way along with product description for uniform classification.
HSN code is designed and introduced by World Customs Organization (WCO) which is being used by more than 200 countries worldwide including India.
Services Accounting Code (SAC) is designed by the Central Board of Excise and Customs (CBEC) to identity each of the services. It assigns a eight digit code for each o the services classified. As of now, there are more than 120 services classified.
SAC code are extended under GST regime so that services can be classified as per this coding mechanism. Hence, SAC is still important even from GST point of view.