Demonetisation, along with recently introduced Goods and Service Tax (GST), may impact the business of upcoming wedding season, staring November, by 10-15 per cent, industry chamber Assocham said here on Monday.Wedding services like marriage garden/marriage hall booking, tent booking, confectionery services and photography are expected to get impacted.At present the Indian wedding industry is about Rs 1 trillion and is growing at 25 to 30 per cent annually. The estimated cost of a wedding with no expenses spared could be between Rs 3 lakh to Rs 8 crore."It is being estimated that the average cost of many wedding services like shopping, tent booking, food services, etc., is higher due to GST. The GST rate on most of these services is from 18 to 28 per cent. Before GST, most of the wedding service businesses like tent services, confectionery booking, etc., were using unregistered bills on which they didn't have to pay any tax," the chamber said. However, Assocham said destination wedding or the wedding tourism sector in India which accounts for less than 10 per cent share in the overall industry is not likely to face much adverse impact of GST and demonetisation as it is already a very costly affair which mainly lures foreigners, NRIs, rich and famous people for exotic weddings at beaches, royal palaces and adventurous places.