3 Charts Show Altcoin Season Has Already Started in May

Altcoins like Ethereum (ETH) and XRP (XRP) may be on the verge of a historic breakout as crypto markets approach a critical post-Bitcoin-Halving milestone.

Altcoins Historically Rally 180 Days After Bitcoin Halvings

According to historical data, major altcoin bull runs tend to begin roughly 180 days after each Bitcoin halving, a pattern that held in 2017 and 2021.

Bitcoin halvings reduce BTC’s supply issuance by 50%, triggering a deflationary effect. After the July 9, 2016, halving, the total altcoin market cap surged from approximately $13 billion to $540 billion by January 2018—a 4,050% increase.

Following the halving on May 11, 2020, the altcoin market rose from $90 billion to $1.7 trillion in less than a year—an over 1,788% jump. The most recent halving occurred on April 20, 2024.

Based on the 180-day cycle, analysts have circled May 13, 2025, as the likely start of a new altseason.

Golden Cross 2025 Echoes 2021’s 150x Altcoin Surge

In another bullish development, the total altcoin market just confirmed a Golden Cross—a technical signal where the 100-day moving average (MA) crosses above the 200-day MA.

The last Golden Cross, on April 19, 2021, preceded a historic altcoin rally. Some low-cap tokens, such as Solana (SOL), gained over 150x from their early-2021 prices within months.

This latest Golden Cross occurred on April 24, 2025, according to the chart, with the total altcoin market cap hovering around $1.3 trillion.

If similar momentum follows, projections suggest a possible 200x market expansion, potentially pushing altcoins past $5 trillion, a level that would exceed the $1.7 trillion peak in May 2021 by nearly 194%.

Altcoin Market Breaks Out of Support, Heads Toward $2T

A new chart of the Crypto Total Market Cap excluding Bitcoin (TOTAL2) reveals a clear ascending channel formation in play since late 2022.

The chart shows the market recently bouncing off its long-term lower trendline support near $950 billion, and now climbing to $1.26 trillion, a +32% gain from its April 2025 low.

This bounce closely mirrors previous rallies off this same support zone, which historically led to retests of the channel’s upper boundary. If the pattern repeats, TOTAL2 could climb toward the $1.8–2 trillion range in the coming months—a potential 40–60% upside from current levels.

Momentum indicators also support the move. The weekly RSI has crossed above 57 for the first time since late 2024, suggesting strengthening bullish momentum.