Bitcoin ETF Inflows Surge as Basis Trade Nears 9%, Signaling Renewed Demand

Spot Bitcoin ETFs listed in the U.S. experienced a surge in institutional investment on May 19th, attracting $667.4 million in net inflows—the highest daily total since May 2nd. This significant influx of capital underscores renewed market confidence, fueled by Bitcoin’s sustained price performance above $100,000 for eleven consecutive days.

The iShares Bitcoin Trust (IBIT) was a primary beneficiary, receiving $306 million in inflows, bringing its total net inflows to $45.9 billion. This highlights the increasing appeal of Bitcoin ETFs as a vehicle for institutional investment.

A key driver behind this renewed interest is the resurgence of the annualized basis trade. This sophisticated strategy involves simultaneously holding long positions in spot Bitcoin ETFs and short positions in CME Bitcoin futures contracts. The widening basis spread, currently approaching 9% (almost double April’s levels), offers highly attractive yields, incentivizing increased participation in this arbitrage opportunity.

Data from Velo indicates a corresponding uptick in basis trade activity, reflected in heightened trading volume on the CME. On May 19th, CME Bitcoin futures volume reached $8.4 billion (approximately 80,000 BTC), the highest since April 23rd. Open interest also saw a notable increase, rising to 158,000 BTC—a gain of over 30,000 contracts from April’s lows. This growth in both volume and open interest demonstrates the expanding appetite for leveraged and arbitrage strategies within the Bitcoin market.

While these figures remain below the peaks observed during Bitcoin’s January all-time high of $109,000, they suggest considerable potential for further expansion. The improved basis spread, having rebounded from below 5% earlier this year to nearly 10%, is likely attracting investors who had previously withdrawn from the market.

Recent 13F filings revealed that the Wisconsin State Pension Board divested its ETF holdings in Q1, likely due to the less favorable basis trade environment at that time. However, given the subsequent widening of the spread and the time lag inherent in 13F data, it’s plausible that they have re-established their positions in Q2 to capitalize on the improved arbitrage opportunity. The overall trend points towards a strengthening market dynamic, characterized by renewed institutional interest and the successful exploitation of arbitrage opportunities.