What Is the Bitcoin Halving? Dates, Rewards and Price Effects

The bitcoin halving is a scheduled cut, written into Bitcoin's code, that halves the number of new coins miners earn for each block they add. So what is bitcoin halving in practice? It happens every 210,000 blocks, roughly every four years, and it is the main reason only 21 million bitcoin can ever exist. The most recent one arrived in April 2024 and dropped the reward to 3.125 BTC per block.

Below are the questions people search most, from the basics through the price debate. For more beginner explainers, browse our crypto section.

What does the bitcoin halving mean in simple terms?

It means the payment for securing the network gets cut in half on a fixed timetable. Miners compete to add the next block of transactions to the blockchain, and the winner collects a block reward. According to the Bitcoin developer guide, that reward has two parts: a block subsidy of brand new coins, plus the transaction fees paid by everyone whose transfer made it into the block.

The halving only touches the subsidy. Picture a mine where, every four years, the seam produces half as much gold per shift no matter how many workers show up. The work continues, but new supply trickles in more slowly each time.

If mining itself is new to you, our guide on how bitcoin mining works walks through the process.

How does the bitcoin halving work?

It works through one rule in the software: count blocks, and each time the count reaches a multiple of 210,000, cut the subsidy in half. In the Bitcoin Core source code, that setting is named nSubsidyHalvingInterval and is set to 210000 for the main network, as you can see in the project's chain parameters file on GitHub.

No company, foundation or person schedules the event. The software calculates the allowed subsidy from the block height, so the cut happens automatically when block number 210,000, 420,000, 840,000 and so on is mined.

Why roughly four years? Blocks arrive about every 10 minutes on average, and the network adjusts mining difficulty every 2,016 blocks to hold that pace. Multiply 210,000 blocks by 10 minutes and you get 2,100,000 minutes, which is about 1,458 days, a little under four years.

When were the past bitcoin halvings?

There have been four so far. The Bitcoin Wiki's controlled supply page lists the block heights and dates:

1. November 28, 2012 (block 210,000): reward fell from 50 to 25 BTC.
2. July 9, 2016 (block 420,000): from 25 to 12.5 BTC.
3. May 11, 2020 (block 630,000): from 12.5 to 6.25 BTC.
4. April 20, 2024 (block 840,000): from 6.25 to 3.125 BTC.

One detail worth noticing: before the 2024 event, Coinbase's explainer projected April 16, 2024. The block actually landed a few days later. Halving dates are always estimates until the block itself is mined, because block times wobble around that 10 minute average.

When is the next bitcoin halving?

The next halving will happen at block 1,050,000, when the subsidy drops from 3.125 to 1.5625 BTC. If blocks keep arriving near the 10 minute target, four years after April 2024 points to 2028, which is why so many people search for the 2028 halving. The Bitcoin Wiki's long range estimate table lists 2029 for that block, a reminder that projections depend on the pace you assume.

Halving countdown clocks work by taking the current block height, subtracting it from 1,050,000 and multiplying the remaining blocks by recent average block times. That is why the estimated date on those clocks drifts by days or weeks as the months go by.

How many halvings are left, and when will the last bitcoin be mined?

About 29 halvings remain. Bitcoin's software tracks rewards in satoshis, the smallest unit (one hundred millionth of a bitcoin), and stores them as whole numbers. After 33 halvings in total, the subsidy shrinks below one satoshi and rounds to zero. The wiki's supply table shows the reward reaching zero at block 6,930,000.

Because of that rounding, the final total lands just under 21 million. The Bitcoin Wiki puts the exact figure at roughly 20,999,999.9769 BTC.

As for timing, Coinbase and the Bitcoin Wiki both point to around the year 2140 for the last fraction of a coin. The wiki adds that putting an exact date, or even a year, on it is difficult, since it depends on how fast blocks arrive over more than a century.

What happens to miners when the reward is cut?

Their income from new coins drops by half overnight, while electricity and hardware costs stay the same. Miners running older, less efficient machines or paying high power rates can see their margins vanish, and some switch off.

The network has a built in shock absorber. If enough miners leave and blocks slow down, the next difficulty adjustment (every 2,016 blocks) makes mining easier, which helps those who stay. Our explainer on what hash rate means covers how that computing power is measured, and if you are tempted to try it yourself, read whether bitcoin mining is profitable at home first.

What happens when all bitcoin have been mined?

Miners will earn only transaction fees. The Bitcoin Wiki describes those fees as the incentive that keeps miners securing the network and making transactions irreversible once the subsidy is gone.

Whether fees alone will be enough to keep mining attractive is a long running debate. Nobody can settle it today, and the question is still more than a century from being tested in full.

Does the bitcoin halving make the price go up?

Not automatically. The halving cuts the flow of new supply, and Coinbase notes this could support the price if demand stays the same or rises. That condition is doing a lot of work.

Price also reacts to interest rates, regulation, ETF flows, exchange failures and plain market mood. The halving is also known years in advance, so traders can factor it in long before it happens. Treat it as one input among many, not a countdown to guaranteed gains. Our piece on why bitcoin goes up and down explains the other forces at play. This is general information, not financial advice.

Does the halving affect people who already own bitcoin?

No, your coins are not cut in half. This is one of the most common myths. The halving changes only how many new coins miners receive per block. Your wallet balance, the 21 million cap and the way you send or receive bitcoin all stay exactly the same.

Fees are not halved either. They rise and fall with how busy the network is.

One final check before you act on halving hype: if someone promises you a sure profit because "the halving is coming," walk away. Guaranteed returns are a classic warning sign, and our guide on how to spot a crypto scam shows what else to watch for.