Bitcoin ETFs could overtake mutual funds by 2028, analyst says

By Elena Vasquez

Spot bitcoin exchange-traded funds (ETFs) held 40.21% of total fund assets in September 2026, and Bloomberg analyst James Seyffart expects them to overtake mutual funds in assets under management (AUM). The two-to-three-year forecast depends on continued acceleration rather than a return to historical growth rates.

Seyffart said: “Their growth is only accelerating. If we stay on the same trend we’ve been on since the summer it will happen in ~two years.” His projection places the threshold at 50%, or roughly half of every dollar in fund assets.

What does the growth forecast actually assume?

Seyffart’s chart placed spot bitcoin ETFs at 40.21% of total fund assets in September 2026. If the three-month growth rate continues, they could reach 50% as early as September 2028, the earlier of the forecast windows cited.

Other projections place the crossover between November 2028 and December 2029, depending on the period considered. The earlier date requires the recent pace to persist for roughly two years.

The quote does not identify which summer or define the trend, which limits testing. The practical consequence would be a shift in client mandates and management-fee revenue toward listed ETF products. The source offers no fee assumptions, issuer forecasts or methodology for the alternative projections, so the dates remain conditional rather than established.

How much buying power does an ETF inflow carry?

Ecoinometrics’ latest analysis estimates that an inflow of 10,000 BTC into spot bitcoin ETFs corresponds to a 3.2% boost in monthly Bitcoin returns. The same amount purchased by public companies contributes an estimated 0.7%, giving ETF demand roughly 4.5 times the influence in the model.

That comparison identifies spot ETF subscriptions as a more direct and consistent source of buying pressure than corporate Bitcoin accumulation, according to the source. It does not establish a causal rule or show how long any estimated return effect persists.

The operational distinction is the route to market: listed funds channel subscriptions into spot purchases, while public companies buy Bitcoin as part of corporate accumulation. The cited model gives those channels sharply different effects on monthly returns. The analysis favors ETF flows as the larger near-term channel for demand, without proving that future returns will follow the same pattern.

What do November’s flows show?

Farisde Investors data shows mostly outflows across spot bitcoin ETFs from November 1 through November 5, 2026. The month-to-date total reached $869.82 million in outflows, with November 4 the only exception at a $74.6 million net inflow.

The source places Bitcoin at $76,102.46 after a 52% decline over the preceding 24 hours. Neither the price figure nor the decline establishes why investors withdrew capital.

The outflows also extended beyond bitcoin. The source reports the following figures:

• Ethereum (ETH) ETFs: $272.09 in outflows, with no unit specified in the source.
• Binance (BNB) ETFs: $271.01 thousand in outflows.
• XRP ETFs: $529.51 thousand in outflows.
• Solana (SOL) ETFs: $1.18 million in outflows.
• Hyperliquid (HYPE) ETFs: $7.66 million in outflows.

The source reads the broader pattern as risk-off sentiment across crypto rather than a Bitcoin-only move. It does not explain the different outflow magnitudes across products. The practical conclusion is that the products remained exposed to a market-wide pullback.

What would test the forecast?

ETF growth was already running above its longer-term pace in September 2026. The rolling 12-month growth rate reached 3.74%, compared with a historical average of 2.78% since the COVID-era market bottom in 2020.

The comparison supports acceleration, but it also identifies the central assumption: a recent three-month pace must continue for roughly two years. The wider estimates allow a much longer window, and the source does not model a slowdown, policy change or shift in investor preferences.

The spot Bitcoin ETF market is about to enter its third year. The next 12 months would test whether its growth rate can hold after the outflow-heavy start to November.

The forecast remains a conditional trend projection rather than a scheduled market event. The earliest checkpoint is September 2028, when the projection reaches 50% of fund assets if the three-month growth rate continues; other estimates extend the wait to December 2029.