Bitcoin Halving Explained: Dates, History and What It Means for Price

A bitcoin halving is a pre-programmed event that cuts the number of new bitcoins paid to miners in half. It happens every 210,000 blocks, roughly every four years, and it is the reason Bitcoin’s supply grows more slowly over time until it stops near 21 million coins.

There have been four halvings so far: November 2012, July 2016, May 2020 and April 2024. Each one reduced the reward miners receive for every new block, from 50 BTC at launch to 3.125 BTC today. The next is expected around spring 2028, when the reward drops to 1.5625 BTC.

This guide covers the full halving schedule, the code-level math behind it, how much new bitcoin each era adds, what past cycles do and do not tell you about price, and why miners feel the halving more than anyone. For the bigger picture on Bitcoin itself, see our pillar guide Bitcoin explained.

What Is the Bitcoin Halving?

Every time a miner adds a valid block to the blockchain, it is allowed to pay itself two things: the transaction fees attached to the payments in that block, and a fixed amount of brand-new bitcoin called the block subsidy. The subsidy is the only way new bitcoin enters circulation. Together, subsidy plus fees make up the block reward.

The halving cuts only the subsidy. Fees are set by users and are unaffected. Because a new block arrives about every 10 minutes on average, 210,000 blocks take close to four years, which is why people talk about a “four-year cycle.”

Nobody votes on a halving and no company schedules it. The rule is written into the software that every full node runs. If a miner tried to claim the old, larger subsidy after a halving, every node would reject its block as invalid. If you are new to how miners and nodes interact, our guide on how bitcoin works walks through a single block step by step.

Bitcoin Halving History: Every Halving So Far

Here is the complete record. Dates are in UTC, and the prices are approximate daily figures, rounded, from widely used price trackers. They are shown for context only.

The 2024 halving had an unusual twist. A new token protocol called Runes launched at the same block, and users competed so hard for space in block 840,000 that it collected about 37.6 BTC in fees, more than ten times its 3.125 BTC subsidy. Fees fell back to normal levels within days, which is a useful reminder that fee spikes tend to be temporary.

When Is the Next Bitcoin Halving? (Bitcoin Halving 2028)

The fifth halving will happen at block 1,050,000. Because it is tied to a block number rather than a calendar date, nobody can name the exact day in advance. You can still estimate it with simple arithmetic.

Most estimates as of October 2026 point to roughly March to May 2028. For a live countdown, check a block explorer or halving tracker, which recalculates from the current height and recent block times.

The Math Behind the Halving: How the Block Subsidy Is Calculated

Bitcoin does not store “the current reward” anywhere. Every node calculates it from the block height using one short rule, found in the GetBlockSubsidy function of Bitcoin Core:

Subsidy = 50 BTC, halved once for every 210,000 blocks that have passed (the number of halvings is the block height divided by 210,000, rounded down).

So block 839,999 paid 6.25 BTC (839,999 ÷ 210,000 = 3.99, rounded down to 3 halvings: 50 ÷ 2³ = 6.25). Block 840,000 paid 3.125 BTC (exactly 4 halvings: 50 ÷ 2⁴ = 3.125).

Internally, the software works in satoshis, the smallest unit of bitcoin (1 BTC = 100,000,000 sats). It halves the subsidy with a binary “right shift,” which drops any fraction of a satoshi. That rounding has two consequences:

• The cap is slightly under 21 million. The maximum possible supply works out to about 20,999,999.9769 BTC.
• The subsidy eventually hits zero. After 32 halvings the subsidy is down to 1 satoshi; at the 33rd it rounds to 0. That happens at block 6,930,000, expected around the year 2140.

After that, miners will earn transaction fees only. Some bitcoin is also permanently lost (forgotten keys, destroyed hard drives), so the number of coins anyone can actually spend will always be lower than the cap.

How Much New Bitcoin Each Era Adds

Because each 210,000-block era pays half as much as the one before, the supply curve flattens fast. Half of all bitcoin that will ever exist was created in the first four years.

The arithmetic is simple: 210,000 blocks × subsidy = new coins per era. Daily figures assume the target of 144 blocks per day (24 hours × 6 blocks per hour).

What this means for bitcoin’s inflation rate

Supply inflation is new coins per year divided by existing coins. In the current era, about 52,560 blocks per year × 3.125 BTC = 164,250 new BTC a year. With a little under 20 million coins in existence as of October 2026, that is roughly 164,250 ÷ 19,900,000 ≈ 0.83% a year.

After the 2028 halving, annual issuance drops to about 82,125 BTC. Divided by roughly 20.35 million coins, that is about 0.4% a year, lower than the long-run growth rate of the above-ground gold supply, which is commonly estimated at around 1.5–2% a year.

Bitcoin Halving and Price: What History Shows

This is the part most people care about, and it is also where the most myths live. Here is what the record shows, without spin.

Three patterns stand out:

• Each past halving was followed by a new all-time high within 12–18 months. That is the basis of the popular “halving cycle” idea.
• The gains have shrunk every time. Roughly 95x, then 30x, then 8x, then about 2x. Bitcoin is far larger than it was in 2012, and it takes much more money to move its price.
• Every peak was followed by a deep drop. After the 2013, 2017 and 2021 highs, bitcoin fell roughly 75–85%. After the October 2025 high, it traded more than 40% lower by spring 2026.

The 2024 cycle also broke an old pattern: bitcoin set a record high in March 2024, a month before the halving, helped by strong demand for newly launched US spot bitcoin ETFs. In earlier cycles the record came well after.

What the Bitcoin Halving Cycle Does Not Prove

Four data points are not a law of nature. Before you treat the halving cycle as a trading plan, weigh these limits:

• The sample is tiny. Four halvings is too few to separate cause from coincidence with any statistical confidence.
• Other forces overlapped. The 2017 run coincided with the ICO boom; 2021 with near-zero interest rates and pandemic stimulus; 2024–2025 with ETF launches and shifting US policy. Any of these could explain much of the move.
• The schedule is public. Everyone knows the date years in advance. In an efficient market, a fully predictable supply change should already be reflected in the price, at least partly.
• The supply shock keeps shrinking. In 2012 the halving removed 3,600 BTC a day of new supply. In 2024 it removed 450 BTC a day, a small amount next to the billions of dollars of bitcoin that change hands daily. In 2028 it will remove 225.

If you want exposure without trying to time any cycle, many people use a fixed schedule instead. See dollar-cost averaging bitcoin for worked examples of how that approach behaved across past cycles.

How the Halving Affects Miners

Whatever happens to price, the halving hits miners directly. Overnight, half of their subsidy income disappears, while their electricity bills, hardware payments and staff costs stay the same.

Miners respond in predictable ways:

• Older, less efficient machines get switched off. When total mining power drops, Bitcoin’s difficulty adjustment (a recalculation every 2,016 blocks, about two weeks) makes blocks easier to find, which restores some revenue to the miners that remain.
• Miners upgrade hardware to newer machines that produce more hashes per watt, and chase cheaper power.
• Some sell more of their bitcoin to cover costs, or consolidate through mergers.

Analysts track a metric called hashprice: expected revenue per unit of computing power per day (usually dollars per petahash per day). It falls by roughly half at each halving, all else equal. To see how mining works and whether it can make sense at home, read Bitcoin mining explained.

Can Fees Replace the Subsidy?

The subsidy pays for Bitcoin’s security. Miners spend real money on electricity to produce blocks, and that cost is what makes rewriting the blockchain prohibitively expensive. As halvings shrink the subsidy toward zero, transaction fees must eventually carry that load.

How well that works is an open question. Fees have spiked during busy periods (such as the 2024 Runes launch) and then fallen back. Some researchers worry about a “security budget” problem decades from now; others expect higher fees per transaction, more activity settled on Bitcoin via second layers, or a higher bitcoin price to compensate. For now, the subsidy still makes up the large majority of miner income on a typical day, and you should be skeptical of anyone who claims certainty either way.

Bottom Line

The bitcoin halving is a fixed rule that cuts new supply in half every 210,000 blocks, and it will keep doing so until around 2140. It makes bitcoin’s issuance schedule predictable and steadily lower, and it squeezes miners every four years. Past halvings were followed by big rallies and even bigger crashes, but with shrinking gains and only four examples, history is a weak guide to what comes after 2028. To keep learning, explore the crypto hub.

Sources

• Satoshi Nakamoto – Bitcoin: A Peer-to-Peer Electronic Cash System
• Bitcoin Core – validation.cpp (GetBlockSubsidy)
• Bitcoin Wiki – Controlled supply
• Bitcoin Developer Guide – Block Chain
• Bitcoin Developer Guide – Mining
• Investor.gov (SEC) – Crypto Assets