U.S. Spot Bitcoin ETF Inflows Near $1B on Sept. 21; Ether ETFs Pull in $270M

U.S. spot Bitcoin exchange-traded funds drew $999 million in net inflows on Sept. 21, putting the day's total just shy of the $1 billion threshold, according to SoSoValue data. BlackRock's iShares Bitcoin Trust (IBIT) led the group with $381 million in net inflows, about 38% of the day's total for U.S. spot Bitcoin ETFs. Net inflows reflect more money entering the funds than exiting over the session and are often used as a gauge of investor demand, though they do not necessarily translate into immediate gains in Bitcoin's price. Flows were also positive for Ether products. U.S. spot Ether ETFs posted $270 million in net inflows on Sept. 21, including $110 million into BlackRock's iShares Ethereum Trust (ETHA), roughly 41% of the category's daily total. Combined, spot Bitcoin and spot Ether ETFs brought in around $1.27 billion in net inflows for the session. BlackRock's IBIT and ETHA contributed $491 million of that amount. The Sept. 21 results bring ETF demand back into focus after mixed daily readings across crypto investment products. Market watchers will be looking to the next sessions to see whether inflows stay positive for both Bitcoin and Ether funds or fade after a single strong day.