{
  "$schema": "https://degreesofsatoshi.com/encyclopedia/schemas/article-v1.json",
  "schemaVersion": "1.0.0",
  "id": "bitcoin-send-max",
  "canonical": "https://degreesofsatoshi.com/encyclopedia/bitcoin-send-max/",
  "collection": "bitcoin",
  "title": "Sending all your bitcoin: why Send Max differs from the displayed balance",
  "description": "Understand Send Max by separating spendable inputs, transaction fees, watch-only balances and the recipient’s final amount.",
  "aliases": [
    "bitcoin send max",
    "bitcoin send max explained"
  ],
  "dates": {
    "published": "2026-10-02",
    "modified": "2026-10-02",
    "verified": "2026-10-02T19:29:20.637Z",
    "dataAsOf": "2026-10-02"
  },
  "authorship": {
    "publisher": "Degrees of Satoshi editorial project",
    "process": "AI-assisted research and drafting with a separate automated source-verification pass; no external expert or named human review is implied."
  },
  "quickAnswer": {
    "text": "Send Max normally asks a wallet to spend selected available funds while leaving enough value for the transaction fee. The recipient therefore receives less than the selected input total. A displayed balance may also include outputs the wallet cannot currently spend or sign for. Read the funded transaction’s recipient amount and fee; the button’s exact selection rules depend on the wallet.",
    "claimId": "bitcoin-send-max-quick-answer",
    "sourceIds": [
      "x425-btc-dev-transactions",
      "x425-btc-core-getbalances",
      "x425-btc-core-walletcreatefundedpsbt"
    ]
  },
  "keyFacts": [
    {
      "label": "Accounting",
      "value": "Inputs equal outputs plus fee",
      "sourceIds": [
        "x425-btc-dev-transactions"
      ],
      "id": "accounting",
      "claimId": "bitcoin-send-max-fact-accounting"
    },
    {
      "label": "Visibility",
      "value": "A watch-only balance is not signing authority",
      "sourceIds": [
        "x425-btc-core-getbalances"
      ],
      "id": "visibility",
      "claimId": "bitcoin-send-max-fact-visibility"
    },
    {
      "label": "Selection",
      "value": "The wallet decides which available outputs to include",
      "sourceIds": [
        "x425-btc-core-walletcreatefundedpsbt"
      ],
      "id": "selection",
      "claimId": "bitcoin-send-max-fact-selection"
    }
  ],
  "prerequisites": [
    "bitcoin-change-addresses",
    "bitcoin-coin-selection"
  ],
  "sections": [
    {
      "id": "arithmetic",
      "heading": "Subtract a fee from spendable inputs",
      "sourceIds": [
        "x425-btc-dev-transactions",
        "x425-btc-core-sendtoaddress"
      ],
      "paragraphs": [
        "If selected inputs total 100,000 satoshis and the final fee is 1,500, a one-output transaction can deliver 98,500 satoshis. That is an illustrative calculation, not a quoted fee for all send-all transactions.",
        "Additional inputs change transaction size. A wallet with many small outputs can pay a different fee from one spending a single output with the same total value."
      ]
    },
    {
      "id": "balance",
      "heading": "Find out what the displayed balance contains",
      "sourceIds": [
        "x425-btc-core-getbalances",
        "x425-btc-core-walletcreatefundedpsbt"
      ],
      "paragraphs": [
        "Core’s documented balances distinguish trusted, untrusted pending and immature value, with a separate watch-only category when present. Other interfaces group these differently. Selected outputs may also require signatures or policies that the current device cannot supply.",
        "Funding a PSBT can include information useful to another signer without making the transaction fully authorized. A maximum amount calculated in a watch-only interface still needs the actual signing path."
      ]
    },
    {
      "id": "review",
      "heading": "Check the final recipient amount",
      "sourceIds": [
        "x425-btc-core-sendtoaddress",
        "x425-btc-core-walletcreatefundedpsbt"
      ],
      "paragraphs": [
        "A fee-subtraction control and a Send Max button are related accounting ideas, but they are not universal synonyms. Verify whether the wallet selected every available output or only a chosen subset, whether it created change and how much the recipient gets.",
        "If the recipient expects an exact invoice amount, a send-all action may underpay it. Fund the requested output and fee separately when that is what the agreement requires."
      ]
    }
  ],
  "faq": [
    {
      "question": "Can I send every satoshi without paying a fee?",
      "answer": "A wallet may permit a particular fee choice, but nodes and miners apply their own policies and selection rules. Send Max typically reserves a fee; it does not guarantee that a zero-fee transaction will be relayed or included.",
      "sourceIds": [
        "x425-btc-dev-transactions",
        "x425-btc-core-walletcreatefundedpsbt"
      ]
    },
    {
      "question": "Why is Send Max lower than my wallet balance?",
      "answer": "The fee reduces the recipient output, and the display may include pending, immature, watch-only or otherwise unavailable value. Compare the selected inputs and their spending conditions with the balance categories.",
      "sourceIds": [
        "x425-btc-core-getbalances",
        "x425-btc-dev-transactions"
      ]
    }
  ],
  "claims": [
    {
      "id": "bitcoin-send-max-quick-answer",
      "articleSlug": "bitcoin-send-max",
      "statement": "Send Max normally asks a wallet to spend selected available funds while leaving enough value for the transaction fee. The recipient therefore receives less than the selected input total. A displayed balance may also include outputs the wallet cannot currently spend or sign for. Read the funded transaction’s recipient amount and fee; the button’s exact selection rules depend on the wallet.",
      "sourceIds": [
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        "source-cd336b4fe95b9402",
        "source-a8abe4366f2656ba"
      ],
      "sourceLocators": [
        {
          "sourceId": "source-b282fdecc069b74d",
          "locator": "Introduction; Spending An Output; P2PKH Script Validation; Multisig; Transaction Fees And Change; Avoiding Key Reuse"
        },
        {
          "sourceId": "source-cd336b4fe95b9402",
          "locator": "Result: mine, watchonly, trusted, untrusted_pending, immature"
        },
        {
          "sourceId": "source-a8abe4366f2656ba",
          "locator": "Arguments: inputs, outputs, options; Result"
        }
      ],
      "scope": {
        "collection": "bitcoin",
        "dataAsOf": "2026-10-02",
        "blockHeight": null
      },
      "qualification": "Educational explanation. Product-specific behavior is scoped to the cited documentation, checked 2026-10-02.",
      "evidenceStatus": "documented",
      "verification": {
        "status": "verified",
        "method": "independent automated source review",
        "checkedAt": "2026-10-02T19:29:20.637Z",
        "reviewer": "Independent automated verification — Codex /root/verify_ethereum_100, separate from the Bitcoin drafting agent",
        "notes": [
          "Checked max-send as eligible input value less the transaction fee, with spendability and unsafe/watch-only distinctions from Core29.98,500sat result checked; PSBT funding alone does not authorize spending."
        ]
      }
    },
    {
      "id": "bitcoin-send-max-fact-accounting",
      "articleSlug": "bitcoin-send-max",
      "statement": "Accounting: Inputs equal outputs plus fee",
      "sourceIds": [
        "source-b282fdecc069b74d"
      ],
      "sourceLocators": [
        {
          "sourceId": "source-b282fdecc069b74d",
          "locator": "Introduction; Spending An Output; P2PKH Script Validation; Multisig; Transaction Fees And Change; Avoiding Key Reuse"
        }
      ],
      "scope": {
        "collection": "bitcoin",
        "dataAsOf": "2026-10-02",
        "blockHeight": null
      },
      "qualification": "",
      "evidenceStatus": "documented",
      "verification": {
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        "checkedAt": "2026-10-02T19:29:20.637Z",
        "reviewer": "Independent automated verification — Codex /root/verify_ethereum_100, separate from the Bitcoin drafting agent",
        "notes": [
          "Checked max-send as eligible input value less the transaction fee, with spendability and unsafe/watch-only distinctions from Core29.98,500sat result checked; PSBT funding alone does not authorize spending."
        ]
      }
    },
    {
      "id": "bitcoin-send-max-fact-visibility",
      "articleSlug": "bitcoin-send-max",
      "statement": "Visibility: A watch-only balance is not signing authority",
      "sourceIds": [
        "source-cd336b4fe95b9402"
      ],
      "sourceLocators": [
        {
          "sourceId": "source-cd336b4fe95b9402",
          "locator": "Result: mine, watchonly, trusted, untrusted_pending, immature"
        }
      ],
      "scope": {
        "collection": "bitcoin",
        "dataAsOf": "2026-10-02",
        "blockHeight": null
      },
      "qualification": "",
      "evidenceStatus": "documented",
      "verification": {
        "status": "verified",
        "method": "independent automated source review",
        "checkedAt": "2026-10-02T19:29:20.637Z",
        "reviewer": "Independent automated verification — Codex /root/verify_ethereum_100, separate from the Bitcoin drafting agent",
        "notes": [
          "Checked max-send as eligible input value less the transaction fee, with spendability and unsafe/watch-only distinctions from Core29.98,500sat result checked; PSBT funding alone does not authorize spending."
        ]
      }
    },
    {
      "id": "bitcoin-send-max-fact-selection",
      "articleSlug": "bitcoin-send-max",
      "statement": "Selection: The wallet decides which available outputs to include",
      "sourceIds": [
        "source-a8abe4366f2656ba"
      ],
      "sourceLocators": [
        {
          "sourceId": "source-a8abe4366f2656ba",
          "locator": "Arguments: inputs, outputs, options; Result"
        }
      ],
      "scope": {
        "collection": "bitcoin",
        "dataAsOf": "2026-10-02",
        "blockHeight": null
      },
      "qualification": "",
      "evidenceStatus": "documented",
      "verification": {
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        "checkedAt": "2026-10-02T19:29:20.637Z",
        "reviewer": "Independent automated verification — Codex /root/verify_ethereum_100, separate from the Bitcoin drafting agent",
        "notes": [
          "Checked max-send as eligible input value less the transaction fee, with spendability and unsafe/watch-only distinctions from Core29.98,500sat result checked; PSBT funding alone does not authorize spending."
        ]
      }
    }
  ],
  "sources": [
    {
      "id": "x425-btc-dev-transactions",
      "label": "Transactions",
      "publisher": "Bitcoin developer documentation",
      "url": "https://developer.bitcoin.org/devguide/transactions.html",
      "locator": "Introduction; Spending An Output; P2PKH Script Validation; Multisig; Transaction Fees And Change; Avoiding Key Reuse",
      "note": "Inputs, outputs, authorization, change, coinbase exceptions and fee accounting.",
      "version": "Developer guide; historical implementation details require qualification",
      "checkedAt": "2026-10-02T18:53:53.759Z",
      "contentSha256": "2f3fc474d51880e6c7fd4c25f747f8d8d8da49a493ab82af8ff4916fa490d6b8",
      "recordId": "source-b282fdecc069b74d"
    },
    {
      "id": "x425-btc-core-getbalances",
      "label": "getbalances RPC",
      "publisher": "Bitcoin Core",
      "url": "https://bitcoincore.org/en/doc/29.0.0/rpc/wallet/getbalances/",
      "locator": "Result: mine, watchonly, trusted, untrusted_pending, immature",
      "note": "Wallet balances are divided by trust and spendability-related categories.",
      "version": "Bitcoin Core 29.0 RPC reference; not a recommendation to install an old release",
      "checkedAt": "2026-10-02T18:53:55.000Z",
      "contentSha256": "bf988ef023ba084bbaf87ceaa30aea5f6d445c36b80be60f9b1fa8f5cf91c0ff",
      "recordId": "source-cd336b4fe95b9402"
    },
    {
      "id": "x425-btc-core-walletcreatefundedpsbt",
      "label": "walletcreatefundedpsbt RPC",
      "publisher": "Bitcoin Core",
      "url": "https://bitcoincore.org/en/doc/29.0.0/rpc/wallet/walletcreatefundedpsbt/",
      "locator": "Arguments: inputs, outputs, options; Result",
      "note": "Funding inputs, watch-only inclusion, fee rate and change outputs.",
      "version": "Bitcoin Core 29.0 RPC reference; not a recommendation to install an old release",
      "checkedAt": "2026-10-02T18:53:55.093Z",
      "contentSha256": "d30514044f4ab73bb52b4f8d9bb2d5b8a64482c26fd1b63be11defcb0f2ac6d6",
      "recordId": "source-a8abe4366f2656ba"
    },
    {
      "id": "x425-btc-core-sendtoaddress",
      "label": "sendtoaddress RPC",
      "publisher": "Bitcoin Core",
      "url": "https://bitcoincore.org/en/doc/29.0.0/rpc/wallet/sendtoaddress/",
      "locator": "Description; Arguments: amount, comment, comment_to, subtractfeefromamount, fee_rate; Result",
      "note": "Fee subtraction changes recipient output; comments remain local metadata.",
      "version": "Bitcoin Core 29.0 RPC reference; not a recommendation to install an old release",
      "checkedAt": "2026-10-02T18:53:55.005Z",
      "contentSha256": "5a7533879c09df8fe7dac0c92fc30ef619b2c0ae9332ab6d388a9bde3e9a583b",
      "recordId": "source-34552f149068cb49"
    }
  ],
  "related": {
    "articles": [
      "bitcoin-change-addresses",
      "bitcoin-coin-selection",
      "bitcoin-fee-rate",
      "bitcoin-payment-not-showing-in-wallet",
      "bitcoin-payment-batching"
    ],
    "dossiers": [],
    "wallets": []
  },
  "revisionHistory": [
    {
      "date": "2026-10-02",
      "kind": "published",
      "summary": "First publication after primary-source research and separate automated verification."
    }
  ],
  "citation": "Degrees of Satoshi editorial project. “Sending all your bitcoin: why Send Max differs from the displayed balance.” Published 2026-10-02; updated 2026-10-02. https://degreesofsatoshi.com/encyclopedia/bitcoin-send-max/"
}