Bitcoin’s total supply is capped at 21 million coins, and the last BTC is expected to be mined around 2140. According to the source material, by 2025, roughly 95% of the total supply had already entered circulation, with more than 19.95 million BTC mined.
That leaves about 1.8 million BTC still to be issued. However, those remaining coins will not enter the market quickly. Bitcoin’s monetary design releases new supply at a steadily declining pace, stretching the issuance of the final portion over many decades.
Halving keeps slowing Bitcoin issuance
The key mechanism behind this schedule is Bitcoin’s halving cycle, which cuts the block reward roughly every four years. The reward started at 50 BTC per block and has now fallen to 3.125 BTC. Each halving reduces the flow of newly minted coins, reinforcing Bitcoin’s scarcity over time.
Because this process continues repeatedly, the remaining supply is released more and more slowly. This is why even though only a small fraction of Bitcoin remains unmined, the network is still expected to take until about 2140 to reach full issuance.
Miners will eventually rely on transaction fees
Once the final Bitcoin is mined, miners will no longer receive revenue from new coin issuance. Instead, they will depend primarily on transaction fees. The source notes that the Bitcoin network is still expected to remain operational, as long as fees continue to provide sufficient incentives for miners.
In that sense, Bitcoin’s long-term sustainability will depend not only on its fixed supply model, but also on whether on-chain activity and fee generation remain strong enough to support network security. For now, the halving mechanism continues to define Bitcoin’s supply trajectory, while the final stage of issuance remains a multi-decade process.