Bitcoin Surges 25% in August, Breaking 9-Year Seasonal Weakness Streak

Bitcoin closed out August—a month traditionally known as a "weak season" for the cryptocurrency—with a gain exceeding 25%, delivering its strongest August rally in nine years. The price started the month around $62,000, briefly surged past $81,000, and then gave back some gains to finish August in the $78,000–$79,000 range.

This monthly gain is the largest since August 2017, when Bitcoin jumped roughly 65%. The move is particularly notable because August has historically been one of the worst months for Bitcoin, with a median return of approximately -7% since 2013.

The primary driver behind the rally was institutional capital. U.S. spot Bitcoin ETFs recorded net inflows of approximately $1.92 billion (~2.6 trillion won) during the week when the uptrend gained momentum. On a monthly basis, cumulative inflows through the 28th reached roughly $3.3 billion (~4.5 trillion won).

On-chain data also clearly captured aggressive buying by large investors. According to analysis from Santiment, so-called "whales"—holders of massive Bitcoin positions—accumulated an additional 39,154 BTC over the past week. At current prices, that amounts to approximately $3 billion (~4.1 trillion won). Total whale holdings now approach 5.22 million BTC.