Overview
The block reward is the primary incentive mechanism that motivates miners to secure the Bitcoin network. When a miner successfully finds a valid proof of work for a new block, they earn the right to include a coinbase transaction that creates new bitcoin and collects all transaction fees from the block.
Halving Schedule
The block reward (subsidy) halves every 210,000 blocks, approximately every four years:
Halving Block Height Reward Approximate Date Total Supply
──────────────────────────────────────────────────────────────────────────
0 0 50.0 BTC Jan 2009 10,500,000
1 210,000 25.0 BTC Nov 2012 15,750,000
2 420,000 12.5 BTC Jul 2016 18,375,000
3 630,000 6.25 BTC May 2020 19,687,500
4 840,000 3.125 BTC Apr 2024 20,343,750
...
33 6,930,000 ~0 BTC ~2140 21,000,000
Block Reward Components
The total reward a miner earns per block consists of two parts:
- Block subsidy: The newly minted bitcoin (currently 3.125 BTC)
- Transaction fees: The sum of all fees paid by transactions included in the block
As the subsidy decreases over time, transaction fees become an increasingly important part of miner revenue, eventually becoming the sole incentive once all 21 million bitcoin have been issued.
Economic Significance
The predictable, decreasing issuance schedule is one of Bitcoin's most important properties. Unlike fiat currencies where central banks can increase the money supply arbitrarily, Bitcoin's supply is mathematically fixed. This predictability allows market participants to accurately forecast future supply, contributing to Bitcoin's value proposition as a scarce digital asset.
Common Misconceptions
Some worry that miners will stop securing the network once the block subsidy becomes negligible. However, if Bitcoin is widely used, transaction fees are expected to provide sufficient incentive. The fee market is already active, with miners earning significant revenue from fees during periods of high demand.