Bitcoin Loses Summer Gains as Ether Dominates Inflows in August

Seasonal trends may not be the most reliable market indicators, but in August, crypto investors saw a pattern hold true — at least for bitcoin.

Historically, market observers have cited old adages like “sell in May and go away,” though their relevance in modern markets is limited. In crypto, a similar notion has emerged: August tends to be a challenging month for prices. This year, that pattern held for bitcoin (BTC).

Despite ongoing inflows into spot ETFs, a dovish pivot from Federal Reserve Chair Jerome Powell, and a record-high price earlier in the month, BTC fell roughly 8% in August. From its August 13 peak above $124,000, bitcoin has dropped nearly 13%, wiping out much of its summer rally and bringing it slightly below its Memorial Day level of $109,500.

Capital Isn’t Unlimited — Ether Sees the Big Money

Meanwhile, ether (ETH) bucked the trend, rising 14% over the month and outperforming BTC by a striking 2,200 basis points. The difference was largely driven by inflows into ETH treasury companies and spot ETH ETFs.

While ETH ETFs initially lagged BTC funds in popularity, inflows surged in August. Through August 28, ETH ETFs received $4 billion in new capital, compared with $629 million for BTC ETFs, according to Bloomberg analyst James Seyffart. Considering ether’s market cap of roughly $500 billion — less than 25% of bitcoin’s $2.1 trillion — these flows were disproportionately large.

In an environment of moderately tight U.S. monetary policy and fiscal pressures from higher tariffs, capital is limited. This month, it appears that ether captured the lion’s share of investor funds, leaving bitcoin to face the brunt of selling pressure.

What September Might Hold

Historical seasonality doesn’t offer much comfort. According to Glassnode, bitcoin has declined in eight of the past twelve Septembers, averaging a loss of 3.8%. While modest gains occurred in four of those years, the historical tendency suggests the month could remain challenging.

On the flip side, twelve data points are hardly a robust sample, and much of the early data (2013–2019) predates bitcoin’s rise as a mainstream asset. As always, historical patterns may offer context but not certainty.