Bitcoin’s issuance rules are written into its code: every 210,000 blocks, the reward for a new block is cut in half. There have been four halvings so far. This article reviews them in chronological order, including the block height at which each occurred and how much the reward was reduced.

Coin mentioned in the article: $BTC Current price: 78,122 (24h +0.59%).

— How is the halving triggered? —

Bitcoin halvings aren’t based on the calendar; they’re based on block height: every 210,000 blocks, the block reward is cut in half. At an average of 10 minutes per block, 210,000 blocks takes about four years, which is why people often say there’s a halving “every four years.”

The block reward is denominated in satoshis in the protocol. Each halving cuts that amount in half. As fewer and fewer new coins are created, this is how the total supply cap of about 21 million is reached.

— The four halvings so far —

The first halving took place on November 28, 2012, at block height 210,000, reducing the block reward from 50 to 25 coins. The second took place on July 9, 2016, at block height 420,000, reducing the reward to 12.5 coins.

The third halving took place on May 11, 2020, at block height 630,000, reducing the reward to 6.25 coins. The fourth took place on April 20, 2024 (UTC), at block height 840,000, reducing the reward to 3.125 coins.

— When is the next one? —

The next halving will occur at block 1,050,000, reducing the block reward from 3.125 to 1.5625 coins. The exact date depends on the actual block production rate at the time. Dates given by countdowns are estimates, and they become more accurate as the event gets closer.

— What does the halving change? —

The halving directly changes how many new coins are created with each block. Miners earn income from both block rewards and transaction fees. As the reward is halved again and again, fees make up an increasingly large share of miners’ income.

The halving is often discussed alongside market cycles, but the protocol doesn’t dictate how prices will move—and so far, there have only been four instances to look at. Separating the rules from interpretations of the market makes it easier not to get swept up in emotion.

— In summary —

You only need to remember a few numbers: the reward is halved every 210,000 blocks; it has been halved four times; the current block reward is 3.125 coins; and the next halving will happen at block 1,050,000. You learn the hard way that it’s best to read the instructions first. Only invest what you can afford, and leave yourself a way out.

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