Altseason refers to a short period when capital shifts from Bitcoin (BTC) to altcoins, leading to a notable, rapid rise in the prices of most cryptocurrencies. Altcoin season, commonly known as "altseason," is characterized by massive gains and high volatility. It's essentially a great time for non-bitcoin maxis.
Over a relatively brief period (typically weeks or months), altcoin prices soar as investors shift funds from Bitcoin to other coins. As prices begin to climb and the altcoin season index trends upward, FOMO (fear of missing out) drives investment. This creates a cascading effect that further drives altcoin prices to extraordinary levels for a limited time.
What causes an altseason?
After a substantial price increase, Bitcoin tends to stabilize and move sideways for a while. This situation prompts investors to seek more profitable opportunities. They often exchange their BTC for Ethereum (ETH) and other promising alts, decreasing Bitcoin's share of the total crypto market and triggering an altseason.
When does altcoin season start in June 2026?
The total crypto market cap is approximately $2.25 trillion, with BTC dominance at 56.35%. That represents a notable decline from the 58–60% range that dominated Q1 2026 and April, and puts dominance below the key 57% level that analysts have flagged as a prerequisite for meaningful capital rotation.
Bitcoin is trading above $66,000, with the latest move driven by a geopolitical catalyst — a US-Iran memorandum of understanding that has boosted global risk appetite — alongside continued institutional accumulation, including a $100 million MicroStrategy purchase on June 16.
The picture is more encouraging than three months ago, but rotation has not been confirmed. A sustained break below 55% BTC dominance is still needed before a broad altcoin rotation can be confirmed, and it has now been over 260 days since the last confirmed altcoin season.
History of past altcoin seasons
Previous altseasons have significantly increased the values of various altcoins, with some achieving exponential rises in relatively short timeframes. Noteworthy alt seasons include 2017–2018 and 2020–2021.
2017–2018
This altseason was driven by a substantial reduction in Bitcoin's market dominance, which fell from 86.3% in late 2017 to 38.69% at the beginning of 2018. During this time, Bitcoin's price fell from a then-historic peak above $20,000 to below $6,000 just a few months later.
The rise of altcoins surpassing BTC coincided with the ICO boom of 2017–2018. Many blockchain projects launched initial coin offerings to raise funds by creating tokens, flooding the market with new assets and new speculators.
2020–2021
The altseason of 2020–2021 emerged during the coronavirus pandemic, prompting retail investors and crypto enthusiasts to seek opportunities beyond Bitcoin. This led to the emergence of the meme coin era, with Dogecoin and Shiba Inu achieving unprecedented growth.
NFTs also boosted alt markets, enhancing overall sentiment across dApp sectors. During this period, BTC's market dominance dropped from 70% to 38%, and the altcoin season index hit 98 on April 16, 2021.
How to tell when altseason has started
Recognizing the start of an altseason requires a solid grasp of market cycles and trends, or you could just check the altcoin season index. The problem is that the index is reactionary: by the time it shows we're in an altseason, it'll be too late to enter at good prices. Here are some key indicators to watch for.
1. Increase in altcoin dominance
A major sign of an altseason is a clear rise in altcoin dominance in the total cryptocurrency market. Alt dominance is the combined market cap of all cryptocurrencies other than Bitcoin, expressed as a percentage of the total market cap of the crypto sector. Analysts have identified a confirmed break below 55% BTC dominance as the key inflection threshold for the current cycle.
2. Rising trading volumes
A spike in trading volumes across various alts is a notable indicator of the beginning of the altcoin cycle. Increased trading volumes reflect heightened activity and growing investor interest, leading to enhanced liquidity and price movements.
When is the next altseason?
Closer than it was in April, but not yet here. The Altcoin Season Index has climbed from the 30s into the high 40s, BTC dominance has dropped nearly four percentage points since its cycle peak, and sentiment has flipped from extreme fear to greed. The structural sequence—Bitcoin rallies, dominance stalls, ETH/BTC turns higher, capital rotates outward—is progressing, but hasn't completed.
One factor that could shift the setup: regulatory clarity is improving, with progress on the CLARITY Act in the US providing more certainty around token classification, reducing a longstanding overhang on altcoin valuations. That clarity could be a meaningful catalyst for specific projects even ahead of a broad altseason.
How to take advantage of the altcoin season
It's important to identify potentially lucrative opportunities before an altseason starts. Here are some key points to consider.
Research and diversify your portfolio
Take the time to analyze and identify the best alts to buy. Sectors like RWA tokenization, next-generation DeFi, and AI infrastructure are attracting the most concentrated capital inflows in 2026, making them worth researching as part of any altcoin strategy. Diversification across sectors can mitigate risk and enhance potential returns.
Time your entries and exits
Consider using technical analysis tools like support and resistance levels and the RSI to determine optimal entry and exit points. These can serve as effective indicators during altcoin seasons and help you track price trends and market sentiment before you decide to invest. Missing the exit often matters more than missing the entry — altseasons end faster than they begin.
Key takeaways
An altcoin is any cryptocurrency other than Bitcoin. It is more volatile than Bitcoin and presents high-risk, high-reward scenarios.
When Bitcoin's dominance drops sharply, it stimulates investments in alts, leading to an altseason.
Forecasting an altseason isn't an exact science, and it isn't formally announced at a specific time or date.
Altseasons can occur multiple times within a year and are often condensed into a relatively short timeframe. Prices of alts can fall as fast as they rise.
In 2026, the altcoin landscape will have over 10 million tokens competing for capital (a fundamentally different environment from 2017 or 2021), meaning the dynamics of past broad altseasons may not repeat in the same form.
Crypto cycles often lead to more hacking and phishing attempts, making it crucial to protect your assets. Cold wallets like Tangem are among the safest ways to store cryptocurrencies, especially during periods of high market volatility.
This content is provided for informational purposes only and should not be construed as investment advice. Investing in Web3 and cryptocurrencies involves risks. It is essential to conduct your own research before engaging with any Web3 apps or cryptocurrencies.
