The last Bitcoin will be mined around 2140. After that, transaction fees replace block subsidies as miner revenue. Here's what that means for Bitcoin's security, scarcity, and long-term holders.
The last Bitcoin will be mined sometime around the year 2140. After that, no new Bitcoin will ever be created — not by any miner, government, or developer. The supply is mathematically fixed forever.
So what keeps the Bitcoin network running when miners can no longer earn new coins?
The short answer: transaction fees. Every Bitcoin transaction already pays a fee to miners. As the block subsidy phases out over the next century, fees become the sole miner revenue — and they're designed to be sufficient to secure the network.
Here's the full picture.
Approximately 94% of all Bitcoin that will ever exist has already been mined. The remaining 6% (roughly 1.27 million BTC) will be released gradually over the next ~115 years through a scheduled process called the block subsidy.
Miners currently earn 3.125 BTC per block (after the April 2024 halving). A new block is mined approximately every 10 minutes. That's about 450 new BTC per day.
This reward halves every 210,000 blocks — roughly every 4 years — in an event called the halving. The progression:
| Halving # | Year (approx.) | Block Reward |
|---|---|---|
| 0 (genesis) | 2009 | 50 BTC |
| 1st | 2012 | 25 BTC |
| 2nd | 2016 | 12.5 BTC |
| 3rd | 2020 | 6.25 BTC |
| 4th | 2024 | 3.125 BTC |
| 5th | 2028 | 1.5625 BTC |
| 6th | 2032 | 0.78125 BTC |
| ... | ... | ... |
| 33rd | ~2140 | ~0 BTC |
After 33 halvings, the block reward will be less than 1 satoshi — effectively zero. The final Bitcoin will be mined around the year 2140. No more halvings, no more new supply, ever. Read more in our Bitcoin halving guide.
Satoshi Nakamoto chose 21 million as the hard supply cap. This number wasn't arbitrary — it falls out of the mathematical sum of the halving series: starting at 50 BTC per block and halving indefinitely, the total converges to approximately 21 million BTC.
The supply cap is enforced by Bitcoin's consensus rules. Every full node on the network independently validates that no transaction creates more Bitcoin than the rules allow. To change the 21 million limit would require convincing every node operator, miner, exchange, and user simultaneously — in practice, impossible. See our why 21 million Bitcoin guide for the full story.
This is the core security question. Miners are the entities that validate transactions and add them to the blockchain. They invest in hardware and electricity. They need revenue to operate. Without revenue, rational miners shut down. Without miners, the network becomes vulnerable to attack.
Today, miner revenue has two components:
As the subsidy declines through each halving, fees must make up an increasing share of miner revenue. By 2140, fees must be the entire source.
This is genuinely debated among Bitcoin economists. The optimistic case:
The fee market scales with Bitcoin's value. If Bitcoin becomes global reserve money — used by billions of people, denominated in hundreds of trillions of dollars of value — then even small fee rates in sat/vB generate massive absolute revenue. A $1 fee on a $10 million settlement is 0.00001% — trivially small for the payer and enormous in aggregate for miners.
Second-layer volume creates on-chain demand. The Lightning Network and future second-layer protocols batch millions of small payments into occasional on-chain settlements. Each settlement pays a fee. A network of billions of Lightning users generates constant settlement pressure on the base layer.
Block space scarcity prices fees upward. Bitcoin blocks have a fixed size (~1-4MB). If more people want to use Bitcoin than blocks can accommodate, fees rise automatically to clear the backlog. This is already visible during bull markets — see our Bitcoin transaction fees guide for how this works.
The pessimistic case: fees today are insufficient to sustain current mining security levels if the block subsidy disappeared overnight. At current fee levels (not prices, but BTC amounts), a fee-only security model requires significantly higher transaction volume than exists today.
Most Bitcoin researchers believe this resolves itself: as Bitcoin's value and adoption grow, fee revenue in dollar terms grows with it. The 2140 timeline also gives more than a century for this transition to play out.
Not in practice — but the theoretical concern is real and worth understanding.
The security budget problem: Bitcoin's security is proportional to the cost of a 51% attack — the amount of money required to control enough mining hash rate to rewrite history. Today, attacking Bitcoin costs billions of dollars. As the block subsidy shrinks, if fees don't compensate, the security budget could shrink too.
Near-term halvings create test cases. The 2024 halving cut miner revenue in half. Miners didn't exit en masse — price appreciation compensated. The 2028 halving will be the next test. Each halving is a live experiment in the fee-vs-subsidy transition. So far, the system has held. Read about the cycle patterns in our Bitcoin 4-year halving cycle guide.
Timeframe context: The full transition from subsidy to fees takes 115 more years. Bitcoin's ecosystem, adoption, value, and fee market will be unrecognizable by then. Treating the year 2140 security model as a near-term crisis misunderstands the timeline.
A separate but related reality: approximately 3-4 million Bitcoin are estimated to be permanently lost — in wallets whose keys no longer exist, on hardware discarded before Bitcoin had value, or in wallets of deceased holders without inheritance plans.
Satoshi Nakamoto's own wallets contain approximately 1 million BTC that have never moved. Most researchers believe these coins are permanently inaccessible.
Effectively, the real circulating supply of Bitcoin is lower than 21 million — perhaps closer to 17-18 million. This makes each remaining Bitcoin even scarcer in practice. If you're concerned about protecting your own coins from loss, see the Bitcoin Inheritance Guide and the Bitcoin Self-Custody Guide.
The final Bitcoin being mined doesn't trigger a price event — the supply cap has been effectively approached for decades by that point. The significance is philosophical and economic, not a sudden shock.
Long before 2140, each halving creates a supply shock: the rate of new Bitcoin production drops 50% while demand (presumably) continues growing. Every halving to date has preceded a substantial price increase within 12-18 months. Whether this pattern holds is uncertain, but it's driven by simple supply-and-demand mechanics — less new supply hitting the market.
For long-term holders, the more relevant question is what the next halving (2028) means for the market cycle. See our Bitcoin price prediction framework and the 4-year cycle strategy guide.
If you're holding Bitcoin with a multi-decade time horizon, here's what the "all mined" dynamic means practically:
Scarcity only increases. With each halving, new supply drops. Lost coins never return. The effective circulating supply trends down over decades.
Hold your keys. If Bitcoin's scarcity makes it increasingly valuable, the risk of loss or theft scales proportionally. Use a hardware wallet — Coldcard Mk4, Trezor Safe 5, or similar — and maintain proper seed phrase backups.
The fee market affects your costs. As block subsidies shrink and the fee market matures, on-chain transaction fees may trend higher during periods of congestion. Timing transactions to low-fee periods and using SegWit/Taproot addresses becomes increasingly worthwhile.
Second-layer usage will grow. Lightning Network and future second-layer protocols will handle most Bitcoin transactions cheaply. Base-layer settlement becomes the expensive, high-value option — appropriate for large transfers, not daily spending.
When will the last Bitcoin be mined? Around the year 2140, after 33 halvings reduce the block reward to effectively zero. About 94% of all Bitcoin has already been mined. The remaining 6% will be released gradually over the next ~115 years.
What happens to miners when all Bitcoin is mined? Miners will earn revenue exclusively from transaction fees. Transaction fees already exist today — they're paid by every Bitcoin transaction. As the block subsidy phases out over the next century, fees are designed to fully replace it.
Will Bitcoin still be secure after all coins are mined? This depends on whether transaction fee revenue is sufficient to keep mining profitable. Most Bitcoin economists believe that as Bitcoin's adoption and value grow, fee revenue will scale to sustain network security. The timeline gives over a century for this transition to occur.
Can the 21 million limit be changed? In theory, it could be proposed — but it would require near-universal consensus from every node operator, miner, exchange, developer, and user in the Bitcoin network. In practice, changing the supply cap is considered nearly impossible and would likely cause a chain split, creating a new coin while the original 21-million-cap Bitcoin continues.
How many Bitcoin are actually in circulation? Approximately 19.7 million BTC have been mined. Of those, an estimated 3-4 million are permanently lost. Effective circulating supply is likely 15-17 million BTC — significantly less than the 21 million hard cap.
Does Satoshi's Bitcoin count toward the 21 million? Yes. The approximately 1 million BTC in wallets attributed to Satoshi Nakamoto count toward the 21 million total. These coins have never moved and are widely believed to be permanently inaccessible — effectively reducing the practical supply.
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