In largely conservative Sri Lanka, women going topless is an offence, while men are allowed to leave their torsos uncovered.
The 26-year-old, whose Thai passport says she is male but who identifies as a woman, pleaded guilty yesterday to two charges of indecent exposure and causing distress to others at Arugam Bay.
A court handed her a suspended six-week sentence after social media posts showed her walking along a touristic beach strip on Monday.
“She was detained at the police station overnight and taken before the magistrate today following a lot of complaints from residents as well as on social media,” a local police officer told AFP.
The magistrate had suspended the sentence for five years, meaning there will be no immediate imprisonment. Any repeat offence, however, would result in her having to serve the six-week term.
Arugam Bay, nearly 400 kilometers (250 miles) from the capital Colombo, is a popular surfing destination.
The local community, largely made up of minority Muslims, had complained to authorities in recent weeks about scantily clad foreigners.
While Sri Lanka, a Buddhist-majority country of 22 million people, welcomes tourists, nudity is prohibited and the general population remains conservative in outlook.
Tourism has long been a key source of foreign exchange for the country, which is still recovering from its worst-ever economic crisis in 2022.
The economy has since stabilised, thanks to an International Monetary Fund bailout in 2023 and the return of tourists following the COVID pandemic.