Bitcoin ETFs had a rough Wednesday. Spot bitcoin and ether ETF products collectively shed more than $520 million in a single session.
BlackRock’s iShares Bitcoin Trust, known as IBIT, recorded approximately $144 million in net outflows on the day in question. That figure lands alongside the previous session’s $161.7 million redemption from the same fund.
Who sold, and how much
Fidelity’s FBTC was the heaviest single contributor to the prior session’s selloff, with $214.8 million leaving the fund.
Bitwise’s BITB, ARK 21Shares’ ARKB, and Grayscale’s GBTC each contributed smaller but meaningful outflows to the overall tally. When combined with ether ETF redemptions, the single-day total crossed $520 million.
To put that number in context: the same group of funds pulled in $731 million in a single day earlier in September.
Total net outflows across U.S. spot bitcoin ETFs reached approximately $450.4 million in the September 15 session alone, which researchers described as the largest single-day redemption figure since June.
Why it’s happening
The short answer is that rising Treasury yields make risk assets less attractive, and bitcoin ETFs are not immune to that dynamic. When the return on a boring government bond climbs, the calculus for holding a volatile asset shifts, and portfolio managers rebalance accordingly.
September’s flow data, taken as a whole, reflects that ambiguity. Through mid-month, cumulative flows for the month were modestly positive at around $17 million, meaning the inflow days and the outflow days had largely offset each other.
IBIT’s position in the market
Despite the recent redemptions, IBIT remains by a wide margin the largest bitcoin ETF by assets. The fund holds approximately $59 billion to $60 billion in net assets.
The fund also added more than $1 billion in bitcoin holdings over a recent 20-day accumulation period.
U.S. spot bitcoin ETFs as a category have accumulated approximately $55 billion in cumulative net inflows since their January 2024 launch.
Spot bitcoin ETFs launched in January 2024 after years of regulatory resistance from the SEC. Their approval represented a structural shift in how traditional finance could access Bitcoin price exposure, and the first several months of trading set records for ETF launch velocity.
The ether ETF market, still newer and smaller than its bitcoin counterpart, added its own outflow contribution to Wednesday’s total.