A Historically Bearish Month Shows Signs of Change
September has long been a challenging month for both traditional and crypto markets. Historically, Bitcoin has averaged a –3.77% dip during this time since 2013, mirroring the S&P 500’s well-documented September slump that dates all the way back to 1928. Seasonal behaviors such as portfolio adjustments, tax-loss selling, and the return of institutional activity after summer are often cited as culprits.
However, the landscape in 2025 offers a slightly different outlook. According to data from BlockByte, Bitcoin's average September decline has eased to –2.55%, with market volatility dropping by nearly 75% compared to earlier cycles. This decline in turbulence is largely attributed to growing ETF adoption and the increasing presence of $BTC on corporate balance sheets—factors that are contributing to the asset’s gradual maturation.
Despite these positive signs, uncertainty remains. Analysts are divided: some point to bullish divergence and suggest that if $BTC can maintain support around the $105K–$110K range, a rally could follow. Others remain cautious, highlighting macroeconomic headwinds, thinning liquidity, and the persistent “September Effect” as potential sources of downside pressure.
While the severity of past September selloffs may be diminishing, the month still warrants a careful approach. $BTC may be evolving, but September has rarely passed without some degree of market turbulence
