Bitcoin halving explained: what it is, when the next one is, what it does

Answer first

A Bitcoin halving is a scheduled cut of the Bitcoin block reward by 50%, occurring approximately every four years. The block reward is the newly-issued Bitcoin that miners earn for adding blocks to the blockchain. Cutting it in half reduces the rate at which new Bitcoin enters circulation.

The most recent halving happened in April 2024, cutting the reward from 6.25 BTC per block to 3.125 BTC. The next halving is estimated for April 2028.

Why halvings exist

Bitcoin has a maximum supply of 21 million coins. Without a mechanism to slow issuance, all 21 million would either be mined too quickly (undermining the fixed-supply design) or too slowly (leaving miners with insufficient incentive after a few decades).

The halving schedule tapers issuance geometrically. Every 210,000 blocks — approximately every four years — the block reward halves. This continues until the block reward reaches zero (after 33 halvings, around the year 2140). By that point, miners will be paid entirely from transaction fees.

The halving history

What halvings actually change

Immediately. The rate at which new Bitcoin enters circulation drops by 50%. In the current cycle (post-April 2024), Bitcoin's annual issuance is roughly 164,250 BTC — about 0.83% of current supply. After April 2028, that will fall to roughly 82,125 BTC per year.

Miner economics. Miners earn block reward + transaction fees. The block-reward drop shifts the miner revenue mix toward fees. Miners with high production costs are squeezed. Mining hash rate can drop briefly around halvings and then recover as inefficient miners drop off.

Not (necessarily) the price. Prior halvings preceded major bull runs, but no economic model has proven the halving causes the price rise. The pattern may be coincidental with growing adoption, or self-fulfilling because market participants expect it. Treat "next halving → new all-time high" as a pattern, not a promise.

Common misunderstandings

• "Halving happens on a specific date." No — it happens at a specific block height. The date is estimated based on average block times.
• "Halving means Bitcoin becomes scarcer." New issuance rate becomes lower. Total supply keeps growing (just more slowly) until the year 2140.
• "Halving guarantees a bull market." No such guarantee. Prior cycles overlap with broader market context.

Related on CoinsCipher

• What is Bitcoin? — the underlying protocol
• How to buy Bitcoin — practical guide