Bitcoin's 500-day rule flips the "buy now, thank me later" sign at halving time ⏳

The "500-day rule," a bitcoin trading pattern anchored to the cryptocurrency's four-year halving cycle, is signaling a buying window beginning in late November and a potential exit window around mid-August 2029, though analysts caution the strategy may prove less reliable in a market now shaped by U.S. spot bitcoin ETFs and institutional flows.

The rule, popularized by Pantera Capital in 2023, holds that investors would historically have profited by buying bitcoin roughly 500 days before a halving and selling about 500 days afterward, with returns of up to roughly 34 times an investor's original stake in prior cycles. The strategy is built on the structure of bitcoin's boom-and-bust cycles, in which reductions in newly mined supply have been followed by sharp price gains.

"BTC has historically bottomed 477 days prior to the halving, climbed leading into it, and then exploded to the upside afterward," Pantera Capital said in a 2023 report. "The post-halving rallies have averaged 480 days from the halving to the peak of that next bull cycle," the article added. A bitcoin halving is programmed to occur every 210,000 blocks, or roughly every four years, cutting the number of new bitcoin awarded to miners per block by 50%. Bitcoin was trading at $64,576.16 at the time of the report.

Some market participants argue the traditional halving-driven four-year cycle is fading as spot bitcoin ETFs and institutional investors now dwarf the new supply introduced by miners, potentially weakening the link between halvings and price action. Others maintain that miner economics continue to anchor bitcoin's long-term market structure, even if the 500-day rule proves less precise as a trading signal. Pro-bitcoin social media accounts have pointed to the framework as evidence that the next accumulation window is approaching, though its accuracy remains untested in this cycle. The next bitcoin halving is still more than a year away, leaving the new buy and sell dates subject to change as the cycle develops.