IBIT vs FBTC vs GBTC: Cumulative Net Flow
Cumulative net flow trajectories for the three dominant US spot Bitcoin ETFs since the 11 January 2024 launch day. BlackRock IBIT (the new-money accumulator), Fidelity FBTC (the steady second), and Grayscale GBTC (the legacy trust bleeding fee-sensitive holders to lower-cost wrappers). The chart visualises the largest intra-product asset rotation in ETF history. AUD-investor framing throughout.
Chart
Three cumulative net-flow lines for the dominant US spot BTC ETFs. IBIT in blue, FBTC in green, GBTC in grey (GBTC is below the zero line because Grayscale has been a net distributor since launch). Hover for the exact running total at any date. Click Fullscreen for a presentation-grade view.
Three issuer stories
- IBIT (BlackRock). The dominant new-money accumulator. BlackRock's institutional distribution muscle (Aladdin platform, wirehouse model-portfolio teams, 401(k) administrator desks, RIA aggregator integrations) is unique in ETF history. IBIT was the default selection when allocator decisions came in. The chart shows the line essentially never went negative on a cumulative basis - every drawdown was small and short-lived.
- FBTC (Fidelity). The consistent second-place. Fidelity has structural advantage in the Fidelity-platform RIA and 401(k) administrator channels. FBTC's flow shape tracks IBIT closely (~0.85 day-to-day correlation) but at roughly 20-25 percent of IBIT's magnitude.
- GBTC (Grayscale). The legacy outflow story. GBTC launched as an ETF with USD 28B AUM inherited from its closed-end-trust pre-existing investor base. The 1.50% expense ratio (vs 0.25% IBIT/FBTC) drove a multi-year rotation out. Grayscale launched the lower-fee BTC Mini Trust (ticker BTC, 0.15% fee) in mid-2024 to capture some of the rotation internally. The GBTC line on the chart sits well below zero throughout the post-launch period.
The GBTC-to-IBIT rotation
The single biggest narrative in spot Bitcoin ETF flow history is the rotation out of GBTC into the lower-fee competitors, primarily IBIT. The mechanics:
- Pre-launch GBTC holders had been locked into the closed-end-trust structure since 2013, watching the premium/discount swing wildly (briefly trading at 100% premium in late 2017, then at 45-50% discount through 2022-2023). Many had stopped seeing GBTC as Bitcoin exposure and started seeing it as a structured product they wanted out of.
- On launch day 11 January 2024 the conversion was complete: GBTC became a redeemable ETF. The pre-existing holders could finally exit at NAV.
- The cost-conscious subset of the GBTC investor base rotated immediately, accepting the tax event in exchange for the 125bp annual fee saving on a low-yielding asset.
- The remainder rotated more slowly through 2024-2025, with the rotation pace decelerating as the "easy rotators" (tax-loss harvest candidates, low-cost-basis holders) cleared. The "stuck holders" with large unrealised gains have stayed.
The cumulative IBIT-minus-GBTC swing (IBIT inflow + |GBTC outflow|) is the cleanest single number for the rotation magnitude.
AU-investor framing
- Allocator-decision signal. The three lines together tell you which institutional bucket is doing what. IBIT line steepening = new-money allocator demand. GBTC line decelerating = the legacy-holder rotation is exhausting. FBTC line steepening = secondary-channel demand is firm.
- Lessons for AU ETF selection. The four AU-listed spot BTC ETFs (EBTC, VBTC, IBTC, BT2K) have not yet seen anything like the GBTC-style legacy-holder rotation; all four launched in 2022 / 2024. But the fee-sensitivity lesson is universal: management expense ratio matters most over multi-year holding horizons. EBTC and VBTC at 0.59% MER are mid-pack globally; IBTC at 0.98% is the highest of the AU four; BT2K at 0.79% sits in the middle.
- Distinct from price. The chart tracks allocator decisions, not BTC price. The lines have continued to extend even during BTC price drawdowns - allocators rebalance to target, they don't all exit because price moved.
Methodology
- Source. Farside Investors daily flow table (farside.co.uk/btc/), filtered to the IBIT, FBTC, and GBTC columns only.
- Cumulative computation. Running sum per issuer of the daily net flow. Computed at build time.
- Sign convention. Positive = net inflow (creations exceed redemptions). Negative = net outflow.
- Static-first. If Farside is unreachable, the bundled seed snapshot is preserved.
Related tools
- Daily spot BTC ETF flows (US) - aggregate daily flow across all eleven issuers.
- Cumulative aggregate flow - the eleven-issuer running total.
- BlackRock IBIT AUM trajectory - the dominant issuer's AUM over time.
- Australian BTC ETF coverage - the AUD-side product class.
Frequently asked questions
They account for roughly 85-90 percent of all US spot Bitcoin ETF AUM. IBIT (BlackRock) is the dominant new-money accumulator, FBTC (Fidelity) is the consistent second-place, and GBTC (Grayscale) is the legacy product (formerly Grayscale Bitcoin Trust, converted from a closed-end trust to ETF on launch day with USD 28B pre-existing AUM). The other eight issuers collectively run a much smaller absolute book, so flow signal from the big three captures the institutional decision.
Two reasons. (1) Fee structure: GBTC charges 1.50% expense ratio vs IBIT/FBTC at 0.25%. For long-horizon holders, that 125bp spread compounds to multi-percent of NAV per year, creating strong incentive to rotate. (2) Inherited investor base: GBTC's pre-launch holders had been locked into the closed-end-trust structure (variable premium/discount) for years; once they could redeem at NAV via the ETF conversion, many took the opportunity to crystallise gains and rotate to lower-fee wrappers.
The numerical difference (IBIT cumulative inflow minus GBTC cumulative outflow) is the net rotation magnitude across the two products. Since launch this swing is in the order of USD 75-85B - real capital that allocators moved out of the legacy high-fee trust into the new low-fee BlackRock wrapper while keeping the same Bitcoin spot exposure. This is the largest intra-product asset rotation in ETF history.
The outflow pace has decelerated meaningfully since launch. The 'reluctant holders' from the closed-end-trust era who wanted to rotate did so in the first 6-12 months. The remaining holders are typically locked in by either large unrealised capital gains (selling triggers tax) or 401(k) / institutional mandates that didn't get updated. Grayscale also launched a low-fee BTC Mini Trust (ticker BTC, 0.15% fee) in mid-2024 to capture some of the outflow internally.
BlackRock has the broadest US institutional distribution network of any asset manager (Aladdin platform, wirehouse relationships, model portfolio integrations). IBIT was therefore the natural default selection for most allocator decisions in the first wave. FBTC's relative gain is in the Fidelity-platform RIA and 401(k) administrator channels where Fidelity has a structural advantage. The two products' flow correlation is ~0.85 - they move together more than they diverge.
Daily issuer-level net flows from Farside Investors public tracker (farside.co.uk/btc/), aggregated cumulatively on the page. Last-known-good fallback if Farside is unreachable.
About the author
