U.S. spot Bitcoin ETFs experienced a significant net outflow of $2.406 billion in May, according to Farside Investors data. BlackRock's IBIT led the withdrawals with a net outflow of $1.411 billion. Other notable outflows included Grayscale's GBTC with $330 million, ARKB with $314 million, and FBTC with $274 million. Additional ETFs such as BITB, EZBC, and BTCO also recorded outflows of $85.6 million, $34.7 million, and $12.2 million, respectively. In contrast, MSBT was the only ETF to report a net inflow, attracting $68.9 million. The overall negative cash flow for U.S. spot Bitcoin ETFs in May highlights ongoing market pressures affecting the cryptocurrency sector.