Bitcoin ETFs finish positive after $433 million Friday inflow; ether funds lose $140 million

U.S. spot bitcoin ETFs ended the week positive after investors added $433 million on Friday, according to The Block's analysis of SoSoValue data. The funds recorded a $6.2 million net inflow for the week ending Sept. 18, compared with $462.7 million in outflows the previous week. The week began with a $160 million inflow on Monday, followed by withdrawals of $450.3 million on Tuesday and $296 million on Wednesday. Thursday brought in $159.5 million, leaving the funds down $426.8 million before Friday's inflow. Friday's $433 million inflow was the largest daily inflow since Sept. 3, when the funds received $730.9 million. Fidelity's FBTC accounted for $310.7 million of Friday's total, while BlackRock's IBIT contributed $108.4 million. FBTC is the second-largest bitcoin ETF by assets under management and trading volume, according to The Block's data. Over the full week, IBIT received $120.7 million and FBTC received $79.9 million. The other bitcoin funds together lost approximately $194.4 million. Bitcoin ETFs remained down about $1.45 billion in net flows for the year. Their cumulative inflows since launch stood at $55.16 billion, and their net assets totaled $102.53 billion on Friday. Bloomberg ETF analyst Eric Balchunas said in a Thursday post on X that bitcoin ETF investors had shown resilience, with cumulative inflows remaining around $55 billion after peaking near $63 billion. He described their staying power as "incredible intestinal fortitude from the Boomers given they saw a 50% drawdown" and said rising stock prices may have helped investors hold on. Spot ether ETFs recorded a $140 million weekly outflow despite receiving $143.8 million on Friday. Three consecutive negative sessions from Tuesday through Thursday drained $404.8 million and ended the funds' four-week inflow streak, during which they had collected a combined $1.94 billion. BlackRock's ETHA received $114.3 million on Friday but ended the week with $56.1 million in outflows. Fidelity's FETH received $26.2 million on Friday but lost $25.8 million for the week. The weekly outflow was the first for ether ETFs since the week ending Aug. 14. The funds remained positive for the year, with approximately $922 million in net inflows. Their net assets stood at $16.72 billion on Friday, compared with $13.25 billion in cumulative inflows since launch. Bitcoin ETF trading volume reached $16.17 billion, up from $8.77 billion the previous week. Ether ETF volume rose to $6.82 billion from $5.14 billion. The previous week had four trading sessions because of Labor Day, while the latest week had an additional session.