The four-year cycle:
what is fixed – and what is interpretation

Anyone who looks into Bitcoin soon encounters a story: every four years the supply of new bitcoin is halved, after which the price rises, overshoots and falls back again. Many charts illustrate this with coloured phases, as if the market ran like clockwork.

That story contains two very different things. One is a rule in the protocol, which every node checks for itself and which cannot be changed without broad agreement across the network. The other is an interpretation of price history, resting on very few observations. Keep the two apart, and you will understand the cycle better than most of those who quote it.

What is fixed: the halving

New bitcoin are created in only one way: whoever finds a valid block may award themselves a fixed reward. This reward is written into the protocol and halves every 210,000 blocks. At an average of around ten minutes per block, that is roughly four years – hence the name.

It began with 50 bitcoin per block. Since then there have been four halvings: on 28 November 2012 (block 210,000), on 9 July 2016 (block 420,000), on 11 May 2020 (block 630,000) and on 20 April 2024 (block 840,000). Today the reward stands at 3.125 bitcoin per block.

Because the reward keeps halving, the total supply approaches a limit: just under 21 million bitcoin. On current reckoning, the last reward will be paid out around the year 2140. After that, no new bitcoin will be created; miners will then receive only transaction fees.

Anyone can recalculate these figures and verify them with their own node. No exchange, no company and no price movement changes any of this. It is the solid ground on which everything else stands.

What is inferred from it: the story of the cycle

The cycle story links the halving to the price. Its mechanics are quickly explained:

• Miners sell continuously. Electricity, equipment and staff cost money. A portion of the new bitcoin is therefore sold on a regular basis.
• The halving halves this flow. Since April 2024, only around 450 new bitcoin per day reach the market instead of around 900.
• If demand stays the same, it meets less new supply. The story concludes: the price rises in the months that follow, sentiment builds on itself, an overshoot follows – and then a decline.

A look at history seems to support this. After the halvings of 2012, 2016 and 2020, marked peaks followed within roughly 12 to 18 months – in December 2013, December 2017 and November 2021 – each followed by a deep decline.

A closer look: how similar were the cycles really?

Comparing the cycles with one another reveals two things. First, the broad shape – rise, peak, decline – repeats. Second, duration, magnitude and course differ considerably. The year after each halving shows this most clearly: the rises grew weaker from cycle to cycle, the timing shifted, and in between there were crashes that had nothing to do with the halving.

Where things stand

For this note, we read the current figures from our own Bitcoin node:

At ten minutes per block, that is a little over 18 months; the next halving is therefore expected in April 2028. The exact day depends on how quickly blocks are actually found.

We have deliberately not addressed where the price stands in the cycle today. Doing so would already be an interpretation with one eye on the future price.

Where the explanation reaches its limits

The cycle is a plausible story – but the evidence for it is thin. The following objections belong alongside it:

• Very few observations. There have been four halvings so far, and therefore three complete cycles. Statistically, almost nothing can be reliably inferred from so few cases. A pattern repeated three times may also be chance.
• New supply keeps shrinking. In 2012 the supply grew by around 12.5% a year; today it grows by about 0.8%. Each further halving therefore removes an ever smaller flow from the market. Even if the mechanism worked in the past, its effect must diminish.
• Other forces are larger. Interest rates and the amount of money available, regulation, exchange collapses and large new groups of buyers move the market strongly. Since January 2024 there have been exchange-traded bitcoin funds in the US; inflows of this kind can mask the effect of the halving.
• A widely known pattern alters itself. When everyone expects a cycle, some act earlier – and thereby shift it.
• Other explanations fit as well. Some analysts see the peaks as following the rhythm of global monetary and interest-rate cycles, which happened to run for similar lengths of time.

Looking ahead: facts and indicators

What we can state with certainty are the rules of the protocol:

No one can say with certainty whether the cycle will remain visible in the price. Instead of a forecast, we set out indicators – signs that the pattern is losing its significance:

• After a halving, the market does not noticeably depart from what would have happened anyway.
• The typical sequence of rise, peak and deep decline blurs or fails to appear.
• The price follows interest-rate and money-supply cycles far more closely than halving dates.

One further consequence is certain and often overlooked: with every halving, the share of miners’ income that comes from new bitcoin falls. In the long run, transaction fees will have to pay for the network’s security. Whether, and how well, that works is one of the most interesting open questions in Bitcoin – regardless of price.

What this means for you

The halving is one of the few facts in Bitcoin you can rely on completely: a rule anyone can verify for themselves. The cycle, by contrast, is a story about the past – instructive, but not a roadmap.

For your security, what matters is not timing but this: that your bitcoin truly belong to you, that you have tested your recovery, and that your family knows what to do if the worst happens.

Sources

• Bitcoin: A Peer-to-Peer Electronic Cash System
• BIP 42: A finite monetary supply for Bitcoin
• Bitcoin Core: block reward calculation (GetBlockSubsidy)
• Block height and issued supply: 21 Fruits’ own Bitcoin Core node, as of 3 October 2026