GST & Billing for MSMEs

What is the difference between CGST, SGST and IGST?

CGST and SGST apply together when a sale happens within the same state: CGST goes to the central government and SGST to the state government, each at half the total GST rate. IGST applies when a sale crosses state borders, and it goes to the central government as a single integrated tax. For example, a 18% GST sale within a state splits into 9% CGST and 9% SGST, while the same sale across states is 18% IGST. OpenBill Pro applies this breakup automatically on invoices and in GSTR-1 export, so a shop owner does not need to calculate it by hand for every bill.