What Happens When a Bitcoin Miner Finds a Block?

A plain-English, vendor-neutral look at what actually happens the moment a miner finds a Bitcoin block: the winning hash, block templates, the coinbase transaction, the 100-block maturity period, and confirmations.

Category: Mining and the Network · Published 2026-07-01

Technically reviewed and sourced on 2026-07-02

What does this mean?

Editorial review covers clarity and neutrality. Technical, security, and source reviews indicate whether an article's material claims were checked against relevant authoritative material. A source link being available does not by itself mean every claim has been verified. A reviewed status means the article's material claims were examined; it does not mean the article is exhaustive or that future protocol, market, or software changes cannot make it outdated.

Finding a block: a hash below the network target

Mining is a guessing game. A miner repeatedly hashes a candidate block header, and a block is found the moment one of those hashes comes out below the network target — a threshold derived from the current network difficulty that every miner on the network shares. There is no progress bar: each attempt is independent, so a block can be found on the first try or after trillions of tries. Difficulty automatically re-adjusts about every two weeks so that blocks are found roughly every ten minutes on average.

Templates come first, then the winning header

Miners and pools do not build a block after finding the answer — they prepare a candidate block template in advance and hash on it.¹ A template is a proposed block: a set of transactions chosen from the mempool (the pool of unconfirmed transactions), plus a coinbase transaction, arranged under a header. When a hash finally meets the target, the miner submits the winning header (and the full block) so it can be checked.

A full validating node then verifies the block against Bitcoin’s consensus rules and, if valid, relays it to its peers, who relay it onward. Two different delays are easy to confuse: the time for a miner to submit its result to its pool (miner-to-pool latency) is not the same as the time for a found block to propagate across the whole network. They are separate measurements.

The coinbase transaction

Every block’s first transaction is the coinbase transaction. It has no ordinary inputs and it creates new bitcoin. Its value is the block subsidy (newly issued coins, which halves roughly every four years) plus the transaction fees from the other transactions in the block. Subsidy and fees are distinct components of the reward.

A coinbase transaction can contain more than one output. It may include a spendable payout output; since SegWit, it also typically includes a zero-value witness commitment output required by the protocol.² Whether a miner is paid directly, or a pool splits the reward among many participants, or a custodial service credits an internal balance instead, is a matter of pool design — not a fixed rule of Bitcoin. In solo mining a pool may pay the finder’s own address directly; in shared pooled mining the reward is distributed among contributors; a custodial pool may credit a balance rather than pay an individual output in the coinbase.

The 100-block coinbase maturity period

A coinbase output cannot be spent immediately. Consensus rules impose a 100-block coinbase maturity period: 100 further blocks must be built on top before the newly created coins become spendable.³ Because blocks are found roughly every ten minutes on average, that is about 16–17 hours on average — but the actual elapsed time varies with real block timing and can be shorter or longer. Until then a wallet typically shows the reward as immature: it is recorded on-chain and belongs to the recipient, but it is not yet spendable.

Confirmations, orphans, and stale blocks

A confirmation is simply another block built on top of the one that contains your transaction. Right after a block is found there is a small chance that a competing block was found at about the same height and the network ends up extending the other chain; the block that is not built upon becomes a stale (sometimes called orphan) block and its reward is not realised. This risk is generally small and decreases as confirmations accumulate, but it is not accurate to describe it as impossible by absolute guarantee. Faster, wider block propagation reduces the chance of losing a race.

Payout models differ — and change variance, not the underlying odds

Different pools pay differently. Solo pools pay the finder the whole reward (minus any fee the pool charges); shared pools pay steadier amounts proportional to contributed work; custodial services may hold balances. Choosing a pool changes the variance (how lumpy or smooth your payouts are) and the fee — it does not change the underlying expected amount before fees, which is set by your share of network hashrate. Always confirm a specific pool’s fee, payout method, and custody model from its own documentation before relying on it.

FAQ

Can I spend a block reward immediately?

No. Coinbase outputs are subject to a 100-block maturity period, which is about 16–17 hours on average but varies with real block timing. Until 100 confirmations pass, the reward is on-chain but not spendable.

Can a coinbase transaction have more than one output?

Yes. A coinbase can include a spendable payout output and, since SegWit, typically a zero-value witness-commitment output required by the protocol. Some pool designs use additional outputs. It is not limited to a single output.

Is a block reward always paid directly to the miner's address?

No. Direct-to-address payout is a pool design choice. Shared pools distribute the reward among contributors, and custodial services may credit an internal balance instead of paying an individual coinbase output.

What is the difference between the subsidy and the fees?

The subsidy is newly issued bitcoin created by the coinbase transaction and halves roughly every four years. The fees are paid by the transactions included in the block. The coinbase pays out both, but they are distinct components.

Could a found block be lost?

Rarely. If a competing block wins a propagation race at the same height, the block not built upon becomes stale and its reward is not realised. The risk is small and shrinks with confirmations, but it is not zero, so it should not be described as impossible.

Key takeaways

A block is found when a hash falls below the shared network target; attempts are independent, not cumulative.
Templates are built before the winning hash; the coinbase can have several outputs, including a zero-value witness commitment.
Coinbase rewards need 100 confirmations (~16–17 hours on average, but variable) before they are spendable.
Whether payout is direct, pooled, or custodial is a pool design choice, not a Bitcoin rule.

Sources

Bitcoin developer documentation — Bitcoin Project
BIP-141: Segregated Witness (witness commitment in the coinbase) — Bitcoin Improvement Proposals
Bitcoin Core consensus source (consensus.h / validation.cpp) — Bitcoin Core project