Bitcoin Spot ETFs Pull In $433M on Friday; Ether Funds Post $140M Weekly Outflow

U.S. spot bitcoin ETFs finished the week in the black after taking in $433 million on Friday, according to The Block's analysis of SoSoValue data. For the week ended Sept. 18, the group posted a net inflow of $6.2 million, reversing from $462.7 million of outflows the prior week. Flows were volatile: $160 million came in on Monday, then $450.3 million left on Tuesday and $296 million on Wednesday. Thursday added $159.5 million, putting the week at a $426.8 million deficit before Friday's rebound. Friday's $433 million was the biggest single-day intake since Sept. 3, when the category drew $730.9 million. Fidelity's FBTC led Friday's haul with $310.7 million, followed by BlackRock's IBIT at $108.4 million. The Block data shows FBTC is the second-largest bitcoin ETF by assets under management and trading volume. Over the full week, IBIT brought in $120.7 million and FBTC added $79.9 million, while the remaining bitcoin funds collectively saw about $194.4 million of outflows. Year to date, spot bitcoin ETFs were still down roughly $1.45 billion in net flows. Since launch, cumulative inflows totaled $55.16 billion, and net assets stood at $102.53 billion on Friday. Bloomberg ETF analyst Eric Balchunas wrote on X on Thursday that bitcoin ETF investors have held up better than expected, with cumulative inflows hovering around $55 billion after peaking near $63 billion. He called it "incredible intestinal fortitude from the Boomers given they saw a 50% drawdown," adding that rising stock prices may have helped investors stay the course. Spot ether ETFs posted a $140 million net outflow for the week despite pulling in $143.8 million on Friday. Three straight down days from Tuesday through Thursday removed $404.8 million, snapping a four-week inflow streak that had brought in a combined $1.94 billion. BlackRock's ETHA took in $114.3 million on Friday but finished the week with $56.1 million of outflows. Fidelity's FETH added $26.2 million on Friday yet ended the week down $25.8 million. It was the first weekly outflow for ether ETFs since the week ended Aug. 14. On the year, the group remained positive at about $922 million in net inflows. Net assets were $16.72 billion on Friday, versus $13.25 billion in cumulative inflows since launch. Trading activity picked up. Bitcoin ETF volume rose to $16.17 billion from $8.77 billion the prior week, while ether ETF volume increased to $6.82 billion from $5.14 billion. The earlier week had four sessions due to Labor Day, while the most recent week included an additional session.