What Is the Bitcoin Halving? Block Subsidy and Dates

A halving is the point at which the fixed subsidy for a new block drops by half. New bitcoin enter circulation in one way only: the miner whose block is accepted pays itself the newly created coins in the first transaction of that block. Satoshi Nakamoto's 2008 paper presents this as an incentive for nodes to support the network, and adds that once a predetermined number of coins are in circulation, the incentive can move entirely to transaction fees.

Nobody votes on a halving. Bitcoin Core sets the interval at 210,000 blocks in its main network parameters, and the subsidy falls by itself when the block height reaches a multiple of that number.

The block subsidy is the amount of new bitcoin the miner of a block may claim; in addition, the miner keeps the fees of the transactions in that block. The genesis block was created with a 50 BTC subsidy, and each halving divides the amount by two: 50, 25, 12.5, 6.25 and now 3.125 BTC.

The network aims for one block every ten minutes and retunes difficulty every 2,016 blocks against a two-week target. At ten minutes a block, 210,000 blocks take about 3.99 years, which is why halvings arrive roughly every four years. Because the interval is counted in blocks rather than calendar time, the real dates drift with actual block times.

The halving table on the Bitcoin Wiki gives the dates below. The fifth halving happens at block 1,050,000 and lowers the subsidy to 1.5625 BTC. At ten minutes per block, that height lies about four years after April 2024, so it had not been reached by 27 October 2026; its exact date depends on block times, and this guide gives no date estimate. Past halvings:

• First: 28 November 2012, block 210,000, subsidy from 50 to 25 BTC.
• Second: 9 July 2016, block 420,000, from 25 to 12.5 BTC.
• Third: 11 May 2020, block 630,000, from 12.5 to 6.25 BTC.
• Fourth: 20 April 2024, block 840,000, from 6.25 to 3.125 BTC.

Each period issues half as many coins as the one before, so the total converges and issuance ends just under 21 million bitcoin. The Bitcoin Wiki puts the ceiling at 20,999,999.9769 BTC and estimates that the last fraction will be mined around 2140, a date that depends on block times.

Adding up the protocol rule gives the theoretical supply at each halving: 10.5 million BTC (50%) at block 210,000, 15.75 million (75%) at block 420,000, 18.375 million (87.5%) at block 630,000 and 19.6875 million (93.75%) at block 840,000. These are theoretical figures; lost or unreachable coins mean the usable amount may be lower.

The bitcoin.org developer documentation describes the block reward as the subsidy plus the fees of the transactions included in the block, both collected through the first transaction of the block. After a halving, fees make up a larger share of a miner's income even if fee levels stay the same. Fees depend on how busy the network is and cannot be known in advance.

If some miners stop operating after the subsidy falls, blocks can arrive more slowly than the target until the next difficulty adjustment.

No. A halving slows the flow of new supply, but the price comes from supply and demand together. The Lzzo.com Bitcoin page notes that the price also responds to institutional demand such as spot ETFs and company treasuries, to global interest rates and liquidity, and to regulation; the halving is one factor among several. The schedule is public years in advance, so the date alone says nothing about direction.

Price moves after past halvings set no rule: four observations are too few for a statistical conclusion, and market conditions were different each time. This guide quotes no post-halving returns, because the result changes with the start date and the period chosen.