Encyclopedia How the network works · Entry 98
Lightning channels: balances, commitments and closing
In this article
At a glance
Key facts
| Fact | Detail | Source |
|---|---|---|
| Funding | Channel establishment commits funds through a Bitcoin funding transaction. | [1] |
| Updates | Participants exchange messages and signatures that advance the channel state. | [1] |
| Exit | Cooperative closing and unilateral commitment-based closing have different requirements. | [1] |
Move claims within an existing allocation
For a simplified example, a channel has 100,000 satoshis of capacity, with 70,000 on Alice’s side and 30,000 on Bob’s. A 10,000-satoshi payment from Alice to Bob shifts the allocation toward 60,000 and 40,000, before accounting for actual reserves, pending HTLCs and fees.
No new bitcoin is created by this update. The parties change which claims can be enforced against the channel’s funding.
A network payment can cross multiple channels
Conditional payments allow a route to link transfers through intermediate nodes. Each hop needs usable capacity in the right direction and acceptable fee and timing conditions.
A large total channel capacity does not guarantee that a particular payment route is available. Capacity placement, pending transfers and individual channel limits affect routing.
On-chain enforcement has costs and timing
Participants may agree on a cooperative close, or a party may publish a commitment transaction under the channel’s rules. Unilateral paths can involve delay and additional transactions.
Keeping correct channel state and responding within relevant timing conditions are part of the security model. A channel is not simply a bank balance that remains safe under every backup or offline behavior.
Direct answers
Questions people ask
Does each Lightning payment create a Bitcoin block transaction?
No. Ordinary channel updates occur off-chain. Funding and closing or dispute-enforcement transactions connect the channel’s state to the Bitcoin chain.
Inspect the evidence
The answer and key facts have stable claim links. These records retain the scope and qualification when reused.
A Lightning payment channel lets participants update their claims on bitcoin committed to a funding output without publishing every payment as a separate Bitcoin transaction. Commitment transactions and channel rules provide on-chain enforcement paths. Opening, closing, liquidity and monitoring requirements still matter.
Scope: Bitcoin · data through 2026-10-02. Verification: verified · 2026-10-02T18:15:23.891Z.
Link to this claimFunding: Channel establishment commits funds through a Bitcoin funding transaction.
Scope: Bitcoin · data through 2026-10-02. Verification: verified · 2026-10-02T18:15:23.891Z.
Link to this claimUpdates: Participants exchange messages and signatures that advance the channel state.
Scope: Bitcoin · data through 2026-10-02. Verification: verified · 2026-10-02T18:15:23.891Z.
Link to this claimExit: Cooperative closing and unilateral commitment-based closing have different requirements.
Scope: Bitcoin · data through 2026-10-02. Verification: verified · 2026-10-02T18:15:23.891Z.
Link to this claimRevision history
- — Initial Bitcoin encyclopedia entry at this permanent URL.
- — 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.- BOLT 2: Peer Protocol for Channel ManagementLightning specification contributors
Channel funding, commitment updates, forwarding and channel closing.
Locator: Channel Establishment; Forwarding HTLCs; Channel Close · Retrieved: 2026-10-02T17:22:20.750ZOpen source - BOLT 7: P2P Node and Channel DiscoveryLightning specification contributors
Direction-specific advertised routing fees and channel update parameters.
Locator: The channel_update Message; HTLC Fees; Example; fee_base_msat; fee_proportional_millionths · Retrieved: 2026-10-02T17:22:20.753ZOpen source
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 correctionsDegrees of Satoshi editorial project. “Lightning channels: balances, commitments and closing.” Published 2026-10-02; updated 2026-10-02. https://degreesofsatoshi.com/encyclopedia/lightning-payment-channels/