Beginner Guide
Bitcoin Halving Explained: How It Works and Why It Matters
Key points
- The halving is written into the Bitcoin code, so nobody votes on it and nobody can switch it off.
- It happens every 210,000 blocks, which works out to roughly every four years.
- There have been four halvings so far, in 2012, 2016, 2020 and 2024, and the next is expected around 2028.
- It reduces how fast new bitcoin is created, and it does not guarantee any price outcome.
How the halving works
Bitcoin runs on proof of work. Miners compete to add the next block of transactions to the chain, and the winner is paid a block reward in newly created bitcoin, plus the fees attached to the transactions in that block. A new block is found about every ten minutes on average, because the network adjusts mining difficulty to keep that pace.
The halving is the rule that sets the size of that reward. When Bitcoin launched in 2009 the reward was 50 bitcoin per block. Every 210,000 blocks, the code cuts it in half. Because the trigger is a block height rather than a calendar date, nobody can say the exact day in advance, only an estimate that tightens as the block gets closer.
Why it matters for bitcoin supply
The halving is the reason bitcoin has a fixed and predictable supply. Each cut slows the flow of new coins, and because every reward is half the one before, the total can never pass 21 million. Most of that supply has already been created, so each new halving makes the remaining issuance smaller again.
This is very different from money issued by a central bank, where the supply can be expanded by decision. With bitcoin, anyone can check the schedule in the code and see exactly how many new coins will be created in each period. That transparency is a big part of why many people describe bitcoin as scarce, and it is worth understanding before you form any view on it. You can see more of our bitcoin research on our bitcoin hub.
Past halvings (2012, 2016, 2020, 2024)
Four halvings have happened so far. Each one fell at a set block height, and each one cut the reward per block in half.
| Halving | Year | Block height | Reward before | Reward after |
|---|---|---|---|---|
| First | 2012 | 210,000 | 50 BTC | 25 BTC |
| Second | 2016 | 420,000 | 25 BTC | 12.5 BTC |
| Third | 2020 | 630,000 | 12.5 BTC | 6.25 BTC |
| Fourth | 2024 | 840,000 | 6.25 BTC | 3.125 BTC |
| Next (expected) | Around 2028 | 1,050,000 | 3.125 BTC | 1.5625 BTC |
The next halving is due at block 1,050,000. Based on the usual ten minute block pace that is expected around 2028, and the estimate will firm up as the network gets closer to that height.
What the halving does not guarantee
It is common to read that the halving always leads to a higher bitcoin price. That is a story built on a handful of past cycles, and a handful of data points is not proof. The halving changes how much new supply arrives, and price also depends on demand, interest rates, regulation, flows into products such as ETFs and the mood of the wider market. Any of those can outweigh a change in issuance.
It is also widely known in advance, so it is not a secret that markets have failed to notice. The honest way to frame it is that the halving is a known change to bitcoin supply, and what that means for the market is uncertain. This guide is education, not a forecast, and it is not a signal to buy or sell.
What happens to miners after a halving
Miners are hit directly, because the reward they earn for each block drops by half overnight. Miners with older machines or higher power costs can find that mining no longer covers their bills, and some switch off. When that happens the network adjusts difficulty, so the remaining miners keep finding blocks at roughly the same pace.
Over time, transaction fees are expected to make up a larger share of what miners earn. Once the last bitcoin is issued, fees will be the only reward, which is one of the long term questions people study when they look at how secure the network will be.
How this differs from our member research guide
This page is a free, plain English explainer of what the halving is and how it works. Our members also have access to our deeper research guide, Your Ultimate Guide to the Bitcoin Halving, which our research team wrote for members and which goes further into the history and our analysis of past cycles.
Frequently asked questions
When is the next bitcoin halving?
The next halving is set for block 1,050,000 and is expected around 2028. Because it is triggered by block height rather than a calendar date, the exact day is only an estimate until the network gets close to that block.
Does the halving raise the bitcoin price?
There is no guarantee. The halving reduces how fast new bitcoin is created, but price also depends on demand and the wider market. Past cycles are a small sample and do not tell you what will happen next time.
What happens to miners when the reward is halved?
Their reward per block drops by half. Less efficient miners may switch off, the network adjusts difficulty to keep blocks coming about every ten minutes, and fees become a bigger share of what miners earn over time.
What is the 21 million cap?
Bitcoin is coded so that no more than 21 million coins can ever exist. Because each halving cuts new issuance in half, the total approaches that limit slowly, with the last fraction expected to be created around 2140.
How often does the bitcoin halving happen?
Every 210,000 blocks. With blocks found about every ten minutes on average, that works out to roughly once every four years.
Related guides
- Halving: glossary definition
- Proof of work: glossary definition
- Bitcoin: glossary definition
- Bitcoin research hub
- Crypto glossary
This guide is general education only and is not personal financial advice. Collective Shift Pty Ltd, ABN 78 650 977 325.
Written by Matt Willemsen, Director of Research, and reviewed by Ben Simpson, Founder of Collective Shift. Published 5 November 2026. Updated 5 November 2026.