Lightning Loop

• Name: Lightning Loop
• URL: https://docs.lightning.engineering/lightning-network-tools/loop.md
• Category: non-custodial Lightning liquidity management / submarine swap bridge / channel rebalancing control plane
• Tags: bitcoin-ecosystem
• Summary: Lightning Loop is best understood as a Lightning liquidity control plane rather than as a simple swap widget or generic bridge. Its official docs and repository describe a non-custodial service from Lightning Labs that uses submarine swaps to move bitcoin between Lightning channels and onchain addresses, with distinct Loop Out and Loop In flows, AutoLoop rules and budgets, static Loop In deposit addresses, instant loop-outs, and authenticated daemon/API access for node operators. The strongest categorization clue is that the product is built around continuous channel-liquidity management for lnd operators, not merely one-off swaps.
• What it does:
  • Lets operators move offchain bitcoin to onchain addresses with Loop Out and move onchain bitcoin into Lightning capacity with Loop In
  • Helps rebalance channels by converting outbound liquidity into inbound liquidity or refilling depleted channels without closing them
  • Supports automated liquidity management with AutoLoop rules, fee caps, budgets, and dispatch limits
  • Provides static Loop In addresses so users can pre-deposit funds onchain and later deploy them into Lightning more quickly
  • Ships as a standalone daemon and CLI, while also being bundled into Lightning Terminal (litd)
  • Exposes gRPC and REST APIs secured with TLS and macaroon auth, while also using L402s for service authentication
• Key claims:
  • The Loop docs describe it as a service for making a Lightning transaction to an onchain Bitcoin address or sending onchain bitcoin directly into a Lightning channel, and explicitly say it uses trustless submarine swaps
  • The same docs say Loop Out transactions are batched to save fees and that Loop uses L402s for authentication
  • The repository README calls Loop a non-custodial off/on-chain bridge and highlights automated channel balancing, privacy-forward swaps, instant Loop Outs, static reusable Loop In addresses, and progress monitoring
  • The get-started docs say Loop comes bundled with Lightning Terminal, can also run standalone, and requires lnd with specific subservers enabled
  • The repository README says loopd connects to an lnd instance, exposes its own gRPC and REST APIs, and secures them with TLS plus loop-specific macaroon authentication
  • The Autoloop docs show that operators can set node-, peer-, or channel-level liquidity rules, budget refresh periods, fee ceilings, and automatic dispatch behavior, which is strong evidence that Loop is an operational liquidity-management tool rather than only a manual swap product
  • The static-address docs say static Loop In addresses are two-of-two taproot multisig timeout addresses, allow pre-deposits and withdrawals without giving up control, and can later be used for near-instant liquidity deployment into Lightning
  • Those static-address docs also warn that the L402 token is part of user identification to the service and losing it can force the user to wait for timeout-based recovery, which is an important trust-model detail
• Whitepaper: No canonical standalone Lightning Loop whitepaper or litepaper surfaced in this pass. The clearest current sources of truth were the official Loop docs and the public lightninglabs/loop repository; see ../whitepapers/lightning-loop-primary-sources-2026-05-02.md.
• Sources:
  • https://docs.lightning.engineering/lightning-network-tools/loop.md
  • https://docs.lightning.engineering/lightning-network-tools/loop/get-started.md
  • https://docs.lightning.engineering/lightning-network-tools/loop/autoloop.md
  • https://docs.lightning.engineering/lightning-network-tools/loop/static-loop-in-addresses.md
  • https://github.com/lightninglabs/loop

Internal linkages

• Broader swap-and-bridging anchor when the operator wants more than the Lightning Labs stack: boltz

• Bundled admin surface that packages Loop into a wider node-operations suite: lightning-terminal

• Direct-peer counterpoint when liquidity stays between existing channel partners instead of going through a service: peerswap

• Last reviewed: 2026-06-02 UTC