A pig-butchering scam or romance baiting scam is a form of online relationship and investment fraud in which perpetrators cultivate fake romantic or social relationships with victims before persuading them to invest money, often in fraudulent cryptocurrency schemes. Such scams are common on social media and dating apps, and often involve catfishing, investment fraud, and romance scams.

Pig-butchering scams involve engaging unsuspecting people online, cultivating trust, and persuading victims to invest, often in fraudulent cryptocurrency schemes that may use fake websites designed to resemble legitimate trading platforms and sometimes provide apparent initial returns to create a false sense of legitimacy.

Contact begins with unsolicited telephone calls with extended or repeated contact, fake profiles on dating apps, or romantic interest from strangers, all with requests for personal information with the aim to financially profile the target. After gaining the victim's trust, the scammer offers too-good-to-be-true rates of return on trades or investments using genuine-looking but fraudulent websites or apps.

The scammer may pressure the victim to invest quickly, offer extravagant gifts which require the release of money, claim difficulties in withdrawing funds from supposed investment returns, and give inconsistent or vague details about the investment. A scammer will often try to isolate their victim by monopolizing their attention away from loved ones, who may otherwise realize the victim is falling prey to a scam.

Perpetrators are typically victims of a fraud factory, where they are lured to travel internationally under false pretenses, trafficked to another location, and forced to commit the fraud by organized crime gangs.

Pig-butchering scams originated in 2016 or earlier as a regional scam in China, originally finding their victims on same-sex dating sites before expanding to opposite-sex dating sites as well. The term "pig butchering" arises from an analogy comparing the initial phase of gaining the victims' trust to the fattening of pigs before slaughtering them.

The modus operandi later spread throughout Southeast Asia at the height of the COVID-19 pandemic. In Sihanoukville, Cambodia—once a prosperous gambling town—many local gambling gangs transformed casinos into scam operation centers performing pig-butchering scams. This was likely a result of a lack of casino attendance on account of the COVID-19 pandemic and the Cambodian government cracking down on commercial gambling.

Many operations are also run from areas of Myanmar which are outside central government control because of the ongoing civil war, with one important hub being the town of Myawaddy in Kayin State, near the border with Thailand. According to the UN Human Rights Office, hundreds of thousands of people have been trafficked and are trapped in scam centers in Cambodia and Myanmar, with other operations being run from Laos, the Philippines and Thailand.

Many of the groups that run pig-butchering scams are overseas Chinese criminal syndicates based in Southeast Asia, who traffic ethnic Chinese and others into fraud factories and force these people to commit the fraud.

Pig-butchering scams gained international momentum through the exploitation of online dating apps and social media platforms. Scammers crafted elaborate fake identities to establish romantic or emotional connections with victims, thus marking a departure from conventional financial scams by integrating psychological manipulation. This early phase of these scams primarily targeted local populations but quickly expanded as digital connectivity grew.

Chainalysis estimated that cryptocurrency fraud totaled about US$12.4 billion in 2024, and reported that pig-butchering scams grew year over year. In October 2023, 12% of Americans using dating apps reported having experienced exposure to this type of fraud, up from 5% in 2018.

The 2023 failure of Heartland Tri-State Bank in Elkhart, Kansas, United States, may have been tied to a pig-butchering scam; CEO Shan Hanes was discovered to have embezzled $47 million from the bank in an attempt to secure funds. Hanes was charged in federal court with embezzlement in February 2024 and pleaded guilty in May 2024. He was later sentenced to 24 years in prison.