Spot Bitcoin ETFs pull in $313M net inflow through first 18 days of September

US spot Bitcoin ETFs have absorbed a net $313.6 million in fresh capital between September 1 and September 18, a number that sounds modest until you look at the turbulence underneath it. Across 13 trading sessions, funds flipped between inflows and outflows almost daily, with only six sessions ending in the green and seven ending in the red. The month’s cumulative figure is the equivalent of a tug-of-war that ended with one side barely dragging the other past the line. But that net positive still matters for a market segment now managing roughly $102.5 billion in total assets. A month of whiplash September 3 alone saw $730.9 million flood into spot Bitcoin ETFs, the kind of single-day surge that can paper over an entire week of outflows. September 18 delivered another jolt, with $433 million in net inflows across the category. Fidelity’s FBTC led that particular charge with $310.7 million, while BlackRock’s IBIT contributed $108.4 million. The big two keep getting bigger If there’s a structural story embedded in September’s flow data, it’s the continued concentration of capital in BlackRock and Fidelity products. Other issuers like Bitwise (BITB), ARK 21Shares (ARKB), and VanEck (H...