When Will Altcoin Season Begin?

Bitcoin is still trading above $100,000, with ETF-related capital inflows on the rise. The big question in the crypto world is when the altcoin season will kick off.

Altcoin season refers to a period when altcoins perform better than Bitcoin. Forbes notes that significant altcoin seasons took place in 2017 and 2021, coinciding with the rise of ICOs, DeFi, NFTs, and Layer-2 solutions.

This phase usually sees investment flowing from Bitcoin into altcoins, leading to substantial price hikes, especially for large-cap and mid-cap altcoins, along with increased trading volume and growing FOMO sentiment.

The Bitcoin Dominance Index (BTC.D) is a crucial indicator for signaling the start of an altcoin season. According to TradingView data, BTC.D stood at 57.8% in late April 2025 before dropping to around 55.2% by mid-May. Currently, Bitcoin dominance sits at 63%.

Renowned cycle analyst Benjamin Cowen suggests that if BTC.D falls below 52%, it could confirm the onset of the altcoin season. However, he warns that not every drop in BTC dominance guarantees an alt season; what matters most is the influx of new capital into altcoins.

Data from CoinShares reveals that over $14 billion has been invested in Bitcoin ETFs since the start of 2025, while capital inflows into ETH and other altcoins remain relatively low at around 8% of total capital. This reflects a cautious approach among institutional investors who still prioritize Bitcoin as the safer crypto asset.

The ETH/BTC pair is currently facing a long-term downtrend, with 0.065 serving as a critical resistance level. Breaking through this level could trigger a shift in market sentiment towards altcoins.

The Altcoin Season Index stands at 24, indicating a “Bitcoin Season.” The Altcoin Month Index is at 57, and the Altcoin Year Index is at 27, all below the 75-point threshold typically required to confirm an altcoin season.

Different forecasts for the 2025 altcoin season exist, with some suggesting it has already begun, while others anticipate a delay due to high BTC dominance and market uncertainties. Institutional capital, emerging sectors like AI and RWA, and macroeconomic factors all play roles in shaping the future of altcoin seasons.

In conclusion, while altcoin season has not officially started, signs point to a potential breakout. The market awaits clearer signals such as a shift in capital from Bitcoin to altcoins, increased retail participation, and a rise in FOMO-driven sentiment, possibly setting the stage for a vibrant altcoin season in the second half of 2025.