The biggest crypto scams in history each took billions of dollars. They include the Prince Group “pig butchering” network (US prosecutors are seeking about 127,271 BTC, worth roughly $15 billion when the case was filed in 2025), FTX (about $8 billion in customer funds misused), PlusToken (estimates from about $2.9 billion to more than $5.8 billion), OneCoin (more than $4 billion), BitConnect (about $2.4 billion), Celsius, and Turkey’s Thodex. Most follow the same pattern: promised returns that can’t be checked, recruitment rewards, and founders who controlled customer money with no outside oversight. Here’s how each worked and what happened next.
- Loss figures are estimates. Prosecutors, bankruptcy courts and analytics firms often disagree, and we give ranges where they do.
- Ponzi-style “investment programs” (OneCoin, PlusToken, BitConnect) and exchanges or lenders that misused deposits (FTX, Celsius, Thodex) account for most of the largest losses.
- Industrial-scale pig butchering is now the fastest-growing category. The FBI’s 2025 IC3 report attributes $7.2 billion in US losses to crypto investment fraud.
- Outcomes vary widely. Some founders got long sentences, one died in custody, and OneCoin’s Ruja Ignatova has been missing since 2017.
- The red flags repeat: guaranteed yields, pressure to recruit, coins you can’t withdraw or check on-chain, and opaque custody.
The biggest crypto scams ranked by estimated losses
The ranking below is approximate, because the methods differ: some figures are investor losses, others are amounts seized or alleged in charges.
| Scheme | Years active | Estimated size | Type | Outcome (as of Oct 2026) |
|---|---|---|---|---|
| Prince Group network | c. 2015–2025 | ~127,271 BTC sought in US forfeiture (~$15B at filing) | Forced-labor scam compounds, pig butchering | Chen Zhi charged in US; arrested in Cambodia and sent to China in Jan 2026; forfeiture pending |
| FTX | 2019–2022 | ~$8B of customer funds misused | Exchange fraud | Sam Bankman-Fried: 25 years; conviction upheld on appeal June 2026 |
| PlusToken | 2018–2019 | Est. $2.9B to $5.8B+; over $4.2B seized | Ponzi “wallet” scheme | 109 arrested in China (2020); ringleaders jailed 2–11 years |
| OneCoin | 2014–2017+ | More than $4B | Fake coin, multi-level marketing | Ruja Ignatova a fugitive; co-founder Greenwood sentenced to 20 years |
| BitConnect | 2016–2018 | ~$2.4B (per US indictment) | Lending Ponzi | Founder Satish Kumbhani indicted 2022, at large |
| Celsius Network | 2017–2022 | Billions in frozen customer deposits | Crypto lender, fraud | Alex Mashinsky: 12 years (May 2025) |
| Thodex | 2017–2021 | Disputed: $24M in Turkish indictment to $2B+ in early estimates | Exchange exit scam | Faruk Fatih Özer sentenced to 11,196 years; died in prison Nov 2025 |
Prince Group: the largest pig-butchering network
How it worked: US prosecutors allege that Cambodia-based Prince Holding Group, led by Chen Zhi, ran compounds where trafficked workers were forced to run “pig butchering” scams. Workers built fake friendships or romances online, then steered victims onto fake investment platforms. In October 2025 the Justice Department charged Chen Zhi with wire fraud and money-laundering conspiracy and filed a civil forfeiture complaint against about 127,271 bitcoin, the largest such action it has filed.
What happened: Cambodia arrested Chen in January 2026 and sent him to China, where he faces fraud and illegal gambling charges. Hong Kong courts froze related assets, and the US forfeiture case was unresolved as of the latest reports. Prince Group denies wrongdoing, and Chen’s lawyers have questioned how the US obtained the bitcoin.
The lesson: the person who befriends you online and coaches you into a “trading platform” is the scam. Our pig butchering scam guide walks through the script stage by stage.
FTX: the largest crypto fraud at a major exchange
How it worked: FTX was one of the world’s largest exchanges. Customer deposits were secretly sent to Alameda Research, Sam Bankman-Fried’s trading firm, and spent on venture bets, property, political donations and loans to insiders. When a run started in November 2022, the money wasn’t there.
What happened: A jury convicted Bankman-Fried on seven fraud and conspiracy counts in November 2023, and he was sentenced to 25 years in March 2024. On June 12, 2026, the Second Circuit unanimously upheld the conviction and sentence. He can still ask the Supreme Court to hear the case, and Justice Department records show he has applied for a pardon. The FTX bankruptcy estate later recovered enough to repay creditors based on the dollar value of their claims at the 2022 bankruptcy date, well below what their crypto would later have been worth.
The lesson: size and celebrity endorsements are not audits. Our explainer on what happens if a crypto exchange shuts down explains how bankruptcy claims work in practice.
PlusToken: the “wallet” that paid you to recruit
How it worked: Marketed mainly in China and South Korea from 2018, PlusToken claimed to be a crypto wallet whose “AI arbitrage” bot earned users high monthly returns, with bonuses for recruiting others. There was no arbitrage. Withdrawals were funded by new deposits until the operators cut off access in mid-2019.
What happened: Chinese police arrested 109 people in 2020, and a court in Yancheng jailed the ringleaders for terms of 2 to 11 years. Authorities said the cryptocurrency involved was worth about 40 billion yuan, and seized coins valued at more than $4.2 billion were forfeited to the state. Estimates of victim losses range from about $2.9 billion to more than $5.8 billion. Analysts also linked PlusToken’s later sell-offs to bitcoin price weakness at the time.
The lesson: any product that pays you to bring in new depositors is funded by those depositors.
OneCoin scam: a coin that never existed
How it worked: Founded in Bulgaria in 2014 by Ruja Ignatova, the self-styled “Cryptoqueen,” OneCoin sold “educational packages” that came with tokens for “mining” OneCoins. There was no public blockchain. Balances were numbers in a company database, and prices were set by the company. A multi-level marketing network sold it worldwide.
What happened: US prosecutors say investors lost more than $4 billion. Ignatova was indicted in 2017 and boarded a flight from Sofia to Athens in October 2017. She hasn’t been seen publicly since. The FBI added her to its Ten Most Wanted list in 2022, and in June 2024 the State Department raised the reward for information to up to $5 million. Bulgarian media reports in 2023 claimed she was killed in 2018, but that hasn’t been confirmed. Co-founder Karl Sebastian Greenwood was sentenced to 20 years in 2023.
The lesson: if you can’t look up the coin on a public block explorer or withdraw it to your own wallet, you don’t own a cryptocurrency.
BitConnect: the lending program with “volatility software”
How it worked: BitConnect let users lend bitcoin-funded BCC tokens to a “trading bot” that supposedly earned up to about 1% a day, plus referral commissions. Its promoters’ YouTube videos and conference appearances became infamous.
What happened: The lending platform shut down in January 2018 after state regulators issued cease-and-desist orders, and BCC collapsed. In February 2022 a US grand jury indicted founder Satish Kumbhani over a scheme that prosecutors say took about $2.4 billion from investors. He remains at large. Several US promoters faced SEC and criminal cases.
The lesson: daily fixed returns from a secret trading algorithm are the classic Ponzi pitch, whatever technology is named.
Celsius: a lender that misled depositors
How it worked: Celsius took customer crypto deposits and paid high yields, telling customers their assets were safe. Prosecutors said it took far bigger risks than it disclosed and propped up its own CEL token. It froze withdrawals in June 2022 and filed for bankruptcy a month later.
What happened: Founder Alex Mashinsky pleaded guilty in December 2024 to one count of commodities fraud and one of securities fraud, and on May 8, 2025, he was sentenced to 12 years in prison. Celsius differs from a pure Ponzi in that it was a real business, but its founder lied about the risks.
The lesson: high yield on deposits means someone is taking risk with your coins. If it isn’t disclosed, assume the worst.
Thodex: Turkey’s exchange exit scam
How it worked: Thodex was a Turkish exchange that ran aggressive promotions. In April 2021 it suddenly halted trading and withdrawals, and its CEO, Faruk Fatih Özer, left the country.
What happened: Özer was arrested in Albania in August 2022 and extradited to Turkey in April 2023. In September 2023 a Turkish court sentenced him and two siblings to 11,196 years in prison. He was found dead in his cell on November 1, 2025, with officials initially describing it as suicide. Loss estimates vary a great deal, from about $24 million in the final Turkish indictment to $2 billion or more in early estimates by analytics firms. The case pushed Turkey to tighten crypto regulation.
The lesson: a small exchange’s withdrawal “maintenance” that drags on without explanation is a warning to get your money out.
Largest crypto fraud patterns: what these cases share
- Guaranteed or fixed returns (daily or monthly) with no verifiable source.
- Recruitment rewards that turn victims into salespeople.
- No independent verification: no public blockchain, no real proof of reserves, no audited accounts.
- Founder control of customer funds, often mixed with the founder’s own businesses.
- Withdrawal friction (fees, “taxes”, delays) that gets worse before a collapse.
- Social proof and urgency: celebrity endorsements, glossy events, “limited” opportunities.
Smaller schemes follow the same script at token level. See what is a rug pull for how founders drain liquidity from new tokens. For the warning signs of today’s common frauds, read our crypto scams guide, and for account and device protection, see the crypto wallets and security hub.
The 2022 Terra collapse is covered separately in our Terra Classic (LUNC) guide, which explains the LUNC burn, the Do Kwon case and scams that still target holders.
How to report crypto fraud
If you’ve lost money, report it quickly and keep records of transaction hashes, wallet addresses, website URLs and messages. In the US, file with the FBI’s Internet Crime Complaint Center (ic3.gov) and the FTC (ReportFraud.ftc.gov). Report investment-related schemes to the SEC or the CFTC, and contact the exchange you sent funds from. Be wary of anyone who offers to “recover” your crypto for an upfront fee. Recovery scams aimed at past victims are common, and law enforcement doesn’t charge to investigate.
FAQ
What is the biggest crypto scam of all time?
It depends on how you measure. By assets targeted, the Prince Group case stands out: US prosecutors are seeking forfeiture of about 127,271 bitcoin, worth roughly $15 billion when filed in 2025. Among exchange frauds, FTX’s misuse of about $8 billion in customer funds is the largest. Among Ponzi schemes, PlusToken and OneCoin each involved billions.
What happened in the OneCoin scam?
OneCoin sold “mining” packages for a cryptocurrency that had no real blockchain. Balances existed only in the company’s database. US prosecutors say investors lost more than $4 billion. Founder Ruja Ignatova disappeared in 2017 and remains on the FBI’s most-wanted list with a reward of up to $5 million. Co-founder Karl Sebastian Greenwood was sentenced to 20 years in prison.
Was BitConnect a Ponzi scheme?
US prosecutors say so. BitConnect promised returns of up to about 1% per day from a “trading bot” plus referral bonuses, paying earlier investors with newer investors’ money. It shut down in January 2018. In 2022 its founder, Satish Kumbhani, was indicted over a roughly $2.4 billion scheme, and he remains a fugitive.
How much was lost in the PlusToken scam?
Estimates vary widely. Chinese authorities said the crypto involved was worth around 40 billion yuan (about $5.8 billion at the time), with more than 2 million participants. Other estimates of investor losses start around $2.9 billion. Authorities seized crypto worth more than $4.2 billion and jailed the ringleaders for 2 to 11 years.
Crypto is volatile and risky; this is education, not financial advice. Do your own research.
