Altseason
Altseason, short for altcoin season, is a market phase in which many altcoins, meaning cryptocurrencies other than Bitcoin, clearly outperform Bitcoin over weeks or months. It is a description of relative performance, not an event that arrives on schedule.
How altseason is defined
There is no official definition. A common approach compares a broad set of large altcoins with Bitcoin over a fixed period. One widely used index, for example, labels it altseason when at least 75% of the top 50 altcoins have outperformed Bitcoin over the previous 90 days. Others simply point to a sustained fall in Bitcoin dominance.
Past episodes most often cited are the late-2017 to early-2018 rally and parts of 2021, when many altcoins rose several times more than Bitcoin within months.
Why it has happened
A frequently described sequence goes like this: Bitcoin rises first and draws attention; Ethereum and other large assets follow; then money moves into smaller, riskier tokens as investors search for bigger gains. Easy liquidity, new narratives and retail enthusiasm feed the last stage.
That sequence is a pattern seen in some cycles, not a law. Market structure has changed, with many more tokens competing for attention, institutional flows that focus on Bitcoin, and large token unlocks that add supply.
An example
Say over three months Bitcoin rises 20%, while a basket of large altcoins rises an average of 80%. Bitcoin dominance falls, and many charts would label the period altseason. If the same basket then drops 60% while Bitcoin drops 30%, the gains can vanish quickly.
Risks and common mistakes
Altseasons have tended to come late in speculative phases and have often ended abruptly, with many altcoins losing most of their value afterwards. Buying small tokens because an altseason is supposedly about to start is one of the most common ways people lose money in crypto. Waiting for one can also mean holding weak projects for years.
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Frequently asked questions
When is the next altseason?
No one can know. Altseasons are recognised mostly in hindsight, and predictions about their timing have often been wrong.
Is Ethereum part of altseason?
Yes. Any cryptocurrency other than Bitcoin is an altcoin, so Ethereum is usually included in altseason measures, often as one of the first to move.
Do all altcoins rise in altseason?
No. Even in strong phases, many tokens lag or fall, and gains tend to concentrate in whichever sectors are popular at the time.
Related terms
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