The Bitcoin halving explained

The Bitcoin halving is one of the few events in crypto that is scheduled years in advance. Roughly every four years, the number of new bitcoin created with each block is cut by 50%. It is built into Bitcoin’s code and is the reason the total supply will never exceed 21 million coins.

How it works

Miners who add a new block to the blockchain receive a block subsidy — freshly created bitcoin — plus transaction fees. The protocol halves that subsidy every 210,000 blocks. With a new block roughly every ten minutes, 210,000 blocks takes about four years.

The history so far

The next halving is expected around 2028, when the reward falls to 1.5625 BTC. The halvings continue until the subsidy becomes too small to divide further, around the year 2140.

Why it matters for supply

The halving cuts the rate at which new bitcoin enters the market. After the 2024 halving, the network issues roughly 450 BTC a day, down from about 900. More than 19.5 million of the 21 million bitcoin have already been mined, so new issuance is now a small fraction of the existing supply.

Why markets watch it

Each previous halving was followed, months later, by a strong bull market. Many traders believe a reduced flow of new coins — which miners often sell to cover costs — tightens supply. Others point out that every cycle also coincided with other big forces, such as interest-rate changes, new investment products and waves of retail interest, and that a small sample of four events can’t prove cause and effect.

What it means for miners

For miners, a halving is an overnight 50% pay cut measured in bitcoin. Operators with older machines or expensive electricity can become unprofitable and switch off, while efficient miners gain share. Over the long term, Bitcoin’s design assumes that transaction fees will gradually replace the block subsidy as the main reward for securing the network — one of the most debated questions about Bitcoin’s future.