Guides / Glossary / Halving
Glossary

Halving: the scheduled cut in new bitcoin

The point, every 210,000 blocks, at which the new bitcoin paid to miners halves.

Education only

Definition. The point, every 210,000 blocks, at which the block subsidy halves. The fourth halving was at block 840,000 on 20 April 2024.

How it works

Each block can pay its miner a block subsidy of newly created bitcoin plus the fees of the transactions it includes. The subsidy started at 50 BTC per block in 2009. Bitcoin Core's code halves it every 210,000 blocks. The first halving was at block 210,000 in November 2012, the second at 420,000 in July 2016, the third at 630,000 in May 2020 and the fourth at 840,000 on 20 April 2024, when the subsidy fell from 6.25 BTC to 3.125 BTC.

The next halving is at block 1,050,000. Because blocks arrive about every ten minutes on average but not exactly, its date can only be estimated. The site's calendar estimates it from the live block height. The halvings continue until the subsidy rounds down to zero, which is why total supply approaches, but never quite reaches, 21 million.

Why it matters for a company

For most companies that hold bitcoin, the halving changes nothing in their own wallets, books or tax. Coins already held are unaffected. It is a change to how much new bitcoin miners receive, not to existing balances.

It matters in three narrower ways. First, a company that mines bitcoin sees its subsidy income halve overnight, which belongs in any mining business plan. Second, over the long term, the security of the network depends more on fees as the subsidy shrinks, an open question that the halving guide and the future watch list discuss without predicting outcomes. Third, halvings attract publicity and price commentary. A treasury policy that sets rules in advance, rather than reacting to headlines, is the useful defence. This site makes no price predictions about halvings.

Example only, fictional. A small company adds the estimated halving month to its board calendar as a reminder to re-read its treasury policy, not as a trading signal, and notes that the policy does not change because of the date.

Common mistakes

Sources

Primary sources only. Each link was checked on 9 November 2026. Rules change, so confirm the current version with your adviser.

  1. Bitcoin Coresrc/validation.cpp: GetBlockSubsidy, 50 BTC halved every 210,000 blocks
  2. Bitcoin Coresrc/kernel/chainparams.cpp: halving interval of 210,000 blocks, 10 minute block target, two week retarget, genesis block
  3. mempool.spaceBlock 840,000, the fourth halving (20 April 2024)
  4. Bitcoin Coresrc/consensus/amount.h: COIN (100,000,000 satoshis) and MAX_MONEY (21 million BTC)
  5. mempool.spaceREST API documentation: block height, hash rate, difficulty adjustment and fee estimates
Education, not advice.

This is general information and education only. It is not financial, investment, tax, accounting, legal or regulatory advice, and it is not a recommendation to buy, sell or hold bitcoin or any other asset. It does not take account of your circumstances or those of your company. You must obtain your own official professional advice to confirm this information is correct before acting on it.

Rules change. This information is correct to our understanding at the last-reviewed date, but it may be incomplete or out of date, and official sources take precedence. Bitcoin is volatile. A company that buys it could lose some or all of the money it puts in.

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