Lightning routing

Lightning payments hop through a path of channels chosen by the sender, wrapped in onion layers so each hop sees only its neighbours. Learn how routing works.

Hopping through channels

If Alice has a channel with Carol, Carol with Dave, and Dave with Bob, then Alice can pay Bob through Carol and Dave.

Who picks the route?

The sender. Alice's node knows the public channel graph (who has channels with whom and their fees) and searches for a path with enough capacity and low fees.

Onion routing

Instructions are wrapped in encrypted layers, like an onion. Each hop peels one layer and learns only the previous and next hop, not the sender, the receiver or its own position in the path.

Routing fees

Each intermediary charges a small fee, usually a fixed base fee plus a proportional rate. Fees are paid by the sender.

Why payments sometimes fail

The sender can't see each channel's exact balance, so a hop might not have enough on the right side. The payment fails safely and the sender tries another route. Nobody loses money.

Multi-path payments

Large Lightning payments can split into several smaller parts that travel different routes and settle together. That makes it easier to send amounts larger than any single channel along the way could carry.

What makes a payment fail?

• No route with enough balance on the right side.
• A node along the path went offline.
• The invoice expired before the payment arrived.

Wallets retry other routes automatically; failed attempts don't cost money.