What is a Lightning node?

A Lightning node is software that takes part in the Lightning Network by opening payment channels with other nodes and passing payments along them. It is separate from a regular Bitcoin node, though it relies on the Bitcoin blockchain to open and close channels. For the bigger picture, see what the Lightning Network is.

What does a Lightning network node do?

A Lightning node keeps track of its channels and their balances, finds routes to other nodes, and sends or receives payments. It can also forward payments for others. Lightning Labs explains that a routing node earns a fee for each successful forward, made of a small base fee plus a rate measured in parts per million of the amount. Each node sets its own fee policy for its channels.

Nodes also share information about the network. Under the Lightning specification's BOLT 7, nodes gossip announcements about channels and nodes so that others can build a map and plan routes.

What is a Lightning node ID?

The node ID is the node's public key. BOLT 7 says it identifies the node and is used to check the signature on the node's announcement. That announcement can also carry a user-chosen alias of up to 32 bytes, a display color, and the addresses where the node can be reached, which may be IPv4, IPv6, a Tor onion service or a DNS hostname. Because anyone can pick any alias, two nodes may share a name, so the node ID is what actually matters.

What is a Lightning channel?

A channel is a shared balance between two nodes, locked in an on-chain bitcoin output. Each channel gets a short channel ID built from the block height, the transaction's position in that block and the output number, written like 539268x845x1. Payments then move inside the channel without new on-chain transactions until the channel closes.

Channels need care. The Bitcoin Design Guide notes that a full backup needs the recovery phrase plus current channel state, and that watchtowers can watch channels while a node is offline and respond if a peer tries to cheat.

How do you run a Lightning node?

You choose an implementation. LND, from Lightning Labs, lists minimum hardware of 2GB of RAM, a quad-core 1 GHz processor and 5GB of storage on an SSD. It can connect to Bitcoin Core or btcd, or run in Neutrino mode without a local Bitcoin node. Core Lightning, maintained by Blockstream and written in C, runs on Linux and macOS and needs a synced Bitcoin Core node of version 25.0 or later, as of November 2026.

Many people install these through node platforms such as Umbrel or myNode, which LND's docs mention, and then control the node from a phone app like Zeus. Running the Bitcoin side is covered in how to run a bitcoin node. A node that routes payments should stay online most of the time, because channels can only forward while it is reachable.