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Encyclopedia How the network works · Entry 81

Coin control: choosing which bitcoin to spend

AI-assisted research · separate automated verificationCorrections

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How the network works
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6 cited records
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Key facts

Key facts for Coin control: choosing which bitcoin to spend
FactDetailSource
SelectionExplicit inputs can be passed to a funding operation.[2]
Exclusionlockunspent can prevent selected outputs from automatic wallet selection.[1]
AuthoritySelection does not replace the signatures required to spend those outputs.[4]
01

Choose receipts rather than just an amount

Suppose a wallet contains one receipt associated with a public donation and another from a private purchase. Automatic selection may combine them. Coin control can let the user inspect that choice and select a different set.

The transaction still reveals the inputs actually used. Selecting only one UTXO does not hide the sender’s interaction with that UTXO or the payment’s outputs.

02

An excluded coin is not frozen by consensus

Bitcoin Core’s lockunspent interface changes the wallet’s automatic selection behavior. A wallet-local lock does not write a restriction onto the blockchain or remove another holder’s ability to use the same keys.

The persistence and interface details are wallet-specific. Read the actual wallet’s behavior rather than assuming every “locked” label describes a consensus timelock.

03

Check whether the selected coins can fund the payment

Choosing smaller receipts may require additional inputs and change the estimated fee. Choosing a large receipt may create a change output that needs to be managed later.

Review the funded transaction after selection. A setting that permits automatic additional inputs may alter the set you initially selected.

Direct answers

Questions people ask

Is coin control the same as a Bitcoin timelock?

No. Coin control is wallet transaction-construction behavior. A consensus timelock is enforced as part of spending validity and cannot be overridden merely by selecting the coin.

Inspect the evidence

The answer and key facts have stable claim links. These records retain the scope and qualification when reused.

Coin control lets a wallet user choose or exclude particular Bitcoin UTXOs when constructing a payment. It can help separate receipts and manage fee trade-offs, but it does not erase their history or make the resulting transaction anonymous. The wallet must still fund the recipient outputs and fee.

Scope: Bitcoin · data through 2026-10-02. Verification: verified · 2026-10-02T18:15:23.891Z.

Link to this claim
Selection: Explicit inputs can be passed to a funding operation.

Scope: Bitcoin · data through 2026-10-02. Verification: verified · 2026-10-02T18:15:23.891Z.

Link to this claim
Exclusion: lockunspent can prevent selected outputs from automatic wallet selection.

Scope: Bitcoin · data through 2026-10-02. Verification: verified · 2026-10-02T18:15:23.891Z.

Link to this claim
Authority: Selection does not replace the signatures required to spend those outputs.

Scope: Bitcoin · data through 2026-10-02. Verification: verified · 2026-10-02T18:15:23.891Z.

Link to this claim
Revision history
  1. — Initial Bitcoin encyclopedia entry at this permanent URL.
  2. — Added reusable claims, explicit source locators, and matching Markdown and JSON. This publishing change does not itself establish factual verification.

Source register

Sources and references

Retrieval dates and locators are recorded individually.
  1. lockunspent RPCBitcoin Core

    Preventing specified wallet outputs from automatic coin selection.

    Locator: Arguments and result fields · Version / scope: Bitcoin Core 29.0.0 RPC · Retrieved: 2026-10-02T17:03:41.086ZOpen source
  2. walletcreatefundedpsbt RPCBitcoin Core

    Input selection, fee units, change output, selected inputs and transaction funding.

    Locator: Arguments and result fields · Version / scope: Bitcoin Core 29.0.0 RPC · Retrieved: 2026-10-02T17:03:40.827ZOpen source
  3. Bitcoin Developer Guide: WalletsBitcoin developer documentation contributors

    Spending keys, address derivation, backups and privacy trade-offs.

    Locator: Wallet Programs; Public Key Distribution-Only Wallets; Hierarchical Deterministic Key Creation · Retrieved: 2026-10-02T17:03:41.163ZOpen source
  4. Bitcoin Developer Guide: TransactionsBitcoin developer documentation contributors

    UTXO inputs, transaction outputs, change and the difference paid as a fee.

    Locator: P2PKH Script Validation; Transaction Fees And Change · Retrieved: 2026-10-02T17:03:41.190ZOpen source
  5. Segregated Witness consensus layerBitcoin BIPs contributors

    Transaction weight and virtual-size definitions in the SegWit specification.

    Locator: Block size; Transaction size · Version / scope: BIP-141; immutable revision pinned in source URL · Retrieved: 2026-10-02T17:22:20.465ZOpen source
  6. OP_CHECKLOCKTIMEVERIFYBitcoin BIPs contributors

    Absolute locktime constraints for spending transaction outputs.

    Locator: Summary; Specification · Version / scope: BIP-65; immutable revision pinned in source URL · Retrieved: 2026-10-02T17:22:20.600ZOpen source
How this article was made

Research and drafting use AI assistance. A separate automated review checks claims against primary sources; no external expert or named human review is implied. Publication, substantive editing, source retrieval and verification are recorded separately. This version was independently checked by an automated reviewer on 2 October 2026.

Editorial method and corrections

Degrees of Satoshi editorial project. “Coin control: choosing which bitcoin to spend.” Published 2026-10-02; updated 2026-10-02. https://degreesofsatoshi.com/encyclopedia/bitcoin-coin-control/