Popularly known as "Pragg", the 18-year-old is the youngest player to reach a chess World Cup final, held last week in the Azerbaijani capital Baku.
Pragg finished with the silver after losing to Carlsen in a nail-biting tiebreak at the International Chess Federation (FIDE) final.
He earned praise from chess legend Garry Kasparov who said Pragg was "very tenacious in difficult positions".
On Wednesday, Pragg was greeted by hordes of supporters who handed him bouquets of flowers and sweets as he emerged from the airport in his home city of Chennai in southern India.
"I am very happy to see so many people have come to receive me... it feels really great," he said, as he stood shyly waving from the sunroof of a car, with a purple and gold scarf draped around his neck.
Such adulation is usually reserved in India for cricket stars, who enjoy celebrity status.
The son of a bank employee and a housewife, the grandmaster has been playing the sport since he was four.
Mother's cooking
Pragg's success has been fuelled by the cooking of his mother Nagalakshmi, who accompanies him on chess tournaments with pots and southern Indian seasonings to make his favourite meal of rice and spicy rasam or sambhar soup.
Nagalakshmi told the ChessBase India news site on Tuesday that she had made rice and sambhar for Pragg at the FIDE World Rapid Team Championship in Dusseldorf, Germany, that followed the Baku event.
Pragg's first coach S. Thiagarajan, who began teaching him at age four, said his student was always dedicated.
"He was always a bright student and a jovial child," Thiagarajan, who coached him at his academy until he was 10, told AFP.
"He used to be in the academy every day from 10:00 am to 7:00 pm, at times staying longer -- and I would give him homework which would take at least three hours to finish," he said.
In 2018 -- aged just 12 years, 10 months and 13 days -- Pragg became the world's then second-youngest chess grandmaster.
Chess has gained in popularity in India in the past two decades after Vishwanathan Anand became the country's first grandmaster aged 18 in 1988 and dominated the game in the 2000s.
A predecessor to chess is thought by some to have originated in India in the sixth century AD, from where it spread to Persia and developed into the "Game of Kings" it is today.
