The South Asian office in Mumbai will oversee Sri Lanka, Pakistan, Bangladesh, Maldives, Mauritius and Seychelles, an S&P statement said.
Tom Schiller, S&P's Asia-Pacific chief, said the Mumbai office will be closer to customers in the region which was growing fast and increasing links to international markets.
"South Asian markets are growing across the entire spectrum of economic activity and are also becoming increasingly globally linked," R. Ravimohan, head of Standard & Poor's South Asia was quoted as saying in the statement.
"Standard & Poor's South Asia will work closely with and leverage the resources of CRISIL to deliver high value services to Indian and other South Asian financial market participants."
In Sri Lanka S&P has issued a sovereign rating and has also rated Sri Lanka Telecom, the island's largest fixed-access telco.
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