India's last Test defeat to Sri Lanka came at Galle in 2015

India's most recent Test defeat to Sri Lanka occurred in the first Test of the 2015 series at the Galle International Stadium. Sri Lanka beat India by 63 runs after India were bowled out for 112 while chasing 176.
India and Sri Lanka have met multiple times in Test cricket and produced several memorable contests. In recent years, Sri Lanka have struggled to consistently challenge India. To find India’s most recent loss to their neighbours requires looking back more than a decade. The new Indian side carried a long-standing unbeaten streak against Sri Lanka in the longest format.
Sri Lanka’s resurgence in the second innings set the match up at Galle. The article described the Test as another example of Galle’s poor fourth-innings conditions and pitches that proved a nightmare for the chasing side. Angelo Mathews led the Sri Lankan team in that match.
India failed to chase the target of 176 and were dismissed for 112, handing Sri Lanka a 63-run victory. The result is described in the article as one of the most shocking defeats for India in what is often called the Golden Era of Test cricket in India. The nature of the collapse at Galle was central to that characterisation.
India recovered in the remainder of the series, winning the next two Tests in Colombo. The Virat Kohli-led Indian side turned the tables in those matches and ultimately won the series 2-1. That comeback ensured the Galle loss did not cost India the series.
The last time India lost a Test series against Sri Lanka was back in 2008. The article was written by Subhomoy Datta.