Bitcoin ETF Flows Turn Positive for 2026 on a $2.4B Week
The week in flows
US spot Bitcoin ETFs closed the reporting week of September 21 through 25 with net inflow of +$2,385.8M, the strongest reporting week bryptoflows has recorded since August. Every session was positive: +$999.0M Monday, September 21 — the category's largest single-day inflow of 2026 — followed by +$714.7M Tuesday, +$346.9M Wednesday, +$190.7M Thursday, and +$134.5M Friday. The week extended a positive streak that began the prior Wednesday to 7 sessions, the category's longest run since the mid-September Fed-week selloff broke the last one.
Measured as a trailing 5-session window rather than a fixed calendar week, this stretch ranks third-strongest of all 184 such windows in 2026, behind only the windows that closed one and two sessions earlier — both of which capture most of the same rally from a slightly different starting day. However it is sliced, this was one of the strongest runs of demand the category has logged all year.
bryptoflows' rolling averages show the momentum decaying gently rather than reversing: the three-session average sits at +$224.0M a day, the five-session (weekly) average at +$477.2M, and the ten-session average still elevated at +$239.2M. The twenty- and sixty-session averages, which carry more of the mid-September weakness, read +$135.7M and +$111.8M respectively. Friday's session alone — the week's quietest — still landed at the 62nd percentile of all 695 sessions on record, with a z-score of +0.18, meaning even the week's weakest day was an ordinary-to-good session by the category's own history, not a reversal.
The most consequential number this week is not a single day's total but a cumulative one. Year-to-date net flow into the category, which stood at -$1,364.5M as of last Friday's close, is now +$1,021.3M — the first positive year-to-date reading of 2026, a swing bryptoflows' own data confirms crossed zero during Monday and Tuesday's sessions. Contemporaneous reporting described Monday's $998.96M print — a figure matching bryptoflows' own $999.0M to within rounding — as the category's biggest single-day inflow of the year, and a follow-up report two days later put the combined three-session total across September 18, 21 and 22 at more than $2.1 billion, describing large short liquidations as bitcoin broke above $84,000-$85,000 that amplified the move on the derivatives side.
Where the moves came from
BlackRock's IBIT did the bulk of the week's work, taking in +$1,157.6M — nearly half the week's net total on its own. Fidelity's FBTC added +$701.6M, and ARK 21Shares' ARKB contributed +$294.7M, its strongest week in months after a rough Fed-week selloff the week before. Morgan Stanley's MSBT added +$203.3M, Bitwise's BITB +$13.9M, and Grayscale's newer BTC mini trust +$8.1M. VanEck's HODL and Franklin Templeton's EZBC were both modestly positive, at +$2.4M and +$4.9M. Only WisdomTree's BTCW finished the week negative, at -$4.0M, and Grayscale's legacy GBTC ended flat-to-positive at +$3.3M — a reversal from the outflows GBTC posted most weeks this year. Invesco Galaxy's BTCO and Valkyrie's BRRR reported exactly zero every session.
Breadth was the week's real story next to the dollar total. Monday's session saw seven of twelve products post a positive flow against zero negative — the broadest single session bryptoflows has logged in weeks. Tuesday and Wednesday stayed broad, at six-of-twelve and four-of-twelve positive with zero negative both days. Only Thursday and Friday saw a single product turn negative (WisdomTree, then Bitwise), and even those sessions stayed net positive on the strength of IBIT and FBTC. bryptoflows' concentration reading closed the week at a product HHI of 0.479 on Friday's session — elevated by an even twelve-way split, but the week overall was far less concentrated than the five-fund, all-negative sessions of the prior Fed-week slide. Life-to-date concentration remains essentially unchanged at a product HHI of 0.403 and issuer HHI of 0.434, since even an unusually broad week barely moves a two-and-a-half-year measure.
Zooming out
Cumulative net flow into the category since inception now stands at $57,615.5M, up from $55,223.6M a week ago. The drawdown from the category's all-time cumulative peak of $62,735.9M has narrowed sharply, to -$5,120.4M, or roughly 8.2% below peak — down from 12.0% last week, the steepest single-week improvement in the drawdown this recap has recorded. Period totals as of Friday's close: week-to-date +$2,385.8M, month-to-date (September) +$2,699.2M, quarter-to-date +$6,411.1M, and year-to-date +$1,021.3M — 2026's first positive year-to-date reading, discussed above.
Strategy: no new filing this week, position's cushion holds near 12%
Strategy has nothing new to disclose this week. The company's most recent 8-K, filed September 21 and covered in full in Thursday's treasury piece, reported a purchase of 950 BTC for $75.7 million for the period September 14-20 — the company's own filing marks that period's direction as acquired, funded from cash on hand rather than new share sales. No filing has landed since; the next is due around September 28, just after this recap's publication. Holdings stand unchanged at 846,000 BTC against a $63.80B cost basis, or $75,416 average cost per coin. Financing capacity is likewise unchanged from the August 31 baseline at $44.34B of undrawn capacity across Strategy's five at-the-market programs.
What moved this week was, again, the market price the unchanged position is marked against. Bitcoin traded at roughly $84,413 on Friday, September 25, per a same-day report, and briefly exceeded $87,000 earlier in the week according to the CryptoTimes coverage cited above — both comfortably above the roughly $84,366 close Thursday's treasury piece used for its own cushion estimate. At Friday's price, the 846,000 BTC position is worth in the neighborhood of $71.4B against its $63.80B cost basis, an unrealized gain of about $7.6B, or roughly 12% above cost — essentially unchanged from Thursday's reading, since bitcoin's price barely moved over the two sessions in between. As always, this mixes bryptoflows' own SEC-sourced cost basis with an externally reported bitcoin price rather than bryptoflows' own candle feed, which remains unavailable in the site's source-freshness check, so it should be read as directional rather than exact.
What to watch
- Whether Strategy's next 8-K, due around September 28, extends the buying from the September 21 filing, returns to a sale, or another quiet week.
- Whether the seven-session flow streak extends into a full second consecutive strong week, or this week's pace was a one-time catch-up after the Fed-week selloff.
- Whether bitcoin holds above $84,000, which matters both for Strategy's cushion and for whether this week's ETF demand was chasing price or leading it.
- Whether the year-to-date flow figure, now positive for the first time in 2026, holds through October or slips back on a weaker stretch.
- The MSCI index-exclusion consultation on Strategy, with comments due September 30 and a decision October 16 — unaffected by anything in this week's flow or price data.
Track the flow data live on the flow pulse overview and ETF flow dashboards, and Strategy's full treasury and financing history on the MSTR breakdown. Flow and attribution figures throughout are read directly from bryptoflows' own API — ETF flows from Farside Investors, Strategy detail from SEC filings — current through the September 25 close and the September 21 filing respectively. Bitcoin price figures in the Strategy section are sourced externally, as noted there, because bryptoflows' own candle feed was reporting unavailable at the time of writing. Retrieved and published September 26, 2026.