Bitcoin ETFs post best month of 2026 as BTC gains 25% in August

US spot Bitcoin ETFs recorded their strongest month of 2026 in August, attracting $3.52 billion in net inflows as Bitcoin gained roughly 25%.

The surge reduced the funds’ year-to-date outflows and pushed total assets higher, signaling stronger institutional demand. However, September opened with $236.46 million in net outflows as BTC briefly fell below $77,000.

Bitcoin ETFs attract $3.52 billion in August

According to SoSoValue data, US spot Bitcoin ETFs attracted approximately $3.52 billion in August, compared with only $172 million in July.

Bitcoin also posted its strongest monthly gain since November 2024. The funds recorded inflows during 16 of 21 trading sessions, including a nine-day streak from August 17 to August 27.

On August 27, Bitcoin ETFs added another $242.3 million, highlighting the acceleration in institutional demand during the second half of the month.

Year-to-date outflows fall 66%

August’s inflows reduced Bitcoin ETF outflows for 2026 from approximately $5.29 billion at the end of July to $1.77 billion.

That represents a 66% improvement. June had been the weakest month, with $4.51 billion in outflows, followed by May with $2.43 billion.

The reversal made Bitcoin ETFs a major source of demand during the August rally.

ETF assets and volume rise

Total net assets across US spot Bitcoin ETFs reached approximately $99.61 billion at the end of August, up from $76.29 billion in July.

Monthly trading volume also rose nearly 49%, from $39.37 billion to $58.63 billion.

BlackRock’s iShares Bitcoin Trust played a major role in the recovery, accounting for a significant share of daily ETF demand. IBIT also drove most of the $216.7 million inflow recorded on August 31.

Related: BlackRock Drives $217M Bitcoin ETF Rebound as Altcoin Funds Extend Inflow Streaks

September reverses momentum

The strong August performance quickly faced a setback.

Bitcoin ETFs recorded $236.46 million in net outflows on September 1, reversing the previous session’s $216.70 million inflow. It was the largest daily outflow since July 31.

The reversal came as Bitcoin fell below $77,000 after trading above $80,000 late in August. The move shows how quickly ETF flows can change when price momentum weakens.

Ethereum and XRP ETFs gain ground

Ethereum and XRP ETFs also strengthened in August.

Ether ETFs moved from approximately $1.12 billion in year-to-date outflows at the end of July to around $732 million in inflows by the end of August.

XRP ETF inflows rose from $343 million to approximately $502 million during the same period.

On September 1, Ether ETFs attracted about $11 million, while XRP ETFs brought in $14.4 million despite Bitcoin ETF outflows. The divergence suggests some institutional capital may be rotating across the crypto market rather than leaving it entirely.

Bitcoin faces a tougher September

Bitcoin’s 25% August gain created strong momentum, but September has started under greater pressure.

Falling ETF demand, higher Treasury yields and broader macroeconomic uncertainty could make it difficult for BTC to repeat August’s performance. If Bitcoin ETF inflows recover, the rally may regain strength. Continued outflows, however, could increase selling pressure.

August remains a major milestone for crypto ETFs, with Bitcoin funds attracting $3.52 billion and Ethereum and XRP products also posting significant gains.

Related: Bitcoin Enters September With 5 Key Risks as Fed Hike Bets Return