Bitcoin, like all precious things, is limited and scarce and therefore won't be issued forever. The distribution of coins will cease at 21 million, more or less around the year 2140. This event, although far away, will affect future miners who will no longer receive new BTC as a reward. Bitcoin mining fees will disappear when the supply of Bitcoin reaches 21 million.
After that, miners will likely only earn income from transaction processing fees and not from a combination of block rewards and transaction fees. The supply of bitcoins is limited to a final limit of 21 million. This is determined by the Bitcoin source code, which was programmed by its creators, Satoshi Nakamoto, and cannot be modified. Once all the bitcoins have been mined, the amount of coins in circulation will remain fixed at that level permanently.
When they stop generating a hash rate, the difficulty decreases and the remaining miners find it easier to find blocks because they represent a larger part of the total hash rate. The sheer scarcity, security, and decentralization of Bitcoin continue to make it a desirable digital asset for buyers. The main consequence of approaching and ultimately reaching the Bitcoin supply limit will be that mining will be much less profitable. Bitcoin miners will be able to continue earning block rewards until a total of 21 million BTC have been minted, after which no new Bitcoin will enter circulation.
By design, the number of bitcoins minted per block is reduced by 50% every 210,000 blocks, or roughly once every four years. In exchange for discovering a block, the miner receives a fixed amount of Bitcoins for their work, which is called a block reward. But it will be another 120 years before the last Bitcoin is minted, due to the gradual reduction in the creation of new bitcoins caused by the process of halving. Even so, the definitive bitcoin isn't likely to be minted until around 2140, based on current estimates.
However, regardless of how Bitcoin evolves, no new bitcoins will be released once the 21 million coin limit is reached. This downward rounding can occur when the block reward for creating a new Bitcoin block is divided in half and the amount of the new reward is calculated. This is because the Bitcoin network uses bit-exchange operators, arithmetic operators that round some decimal points to the nearest smallest integer. The time it takes to mine a bitcoin depends on the amount of the reward per block or how many new bitcoins are paid to cryptocurrency miners for generating a new block.
Once the 21 million BTC have been mined, the network will work practically the same as it does now, but with one crucial difference for miners. The fact that Bitcoin reaches its maximum supply limit is likely to affect Bitcoin miners, but how they are affected depends in part on how Bitcoin evolves as a cryptocurrency. Since the satoshi is the smallest unit of measurement in the Bitcoin network, it cannot be split in half.
