Definition
A channel factory is a multi-party Lightning construction in which a group of users cooperatively lock their funds into a single on-chain multisignature output, then create many payment channels among themselves off-chain from that shared pool. The goal is to drastically reduce the on-chain footprint of channel management: instead of one blockchain transaction per channel opened or closed, a whole set of channels can be created, resized, and torn down with far fewer settlements to the base layer.
How the pooling works
The participants first build one funding transaction that spends their individual inputs into a single n-of-n multisig output. From that pooled capacity they allocate sub-channels between pairs of members. For example, if Alice, Bob, and Harry each commit 1 BTC, the factory holds 3 BTC and each member can open channels with the other two, all without further on-chain transactions. Channels inside the factory can be opened, closed, and rebalanced by updating off-chain agreements, touching the blockchain only when the factory itself is created or finally dissolved.
Why it matters for scaling
On-chain block space is the scarcest resource in Bitcoin, so amortizing many channels over one UTXO improves the ratio of Lightning capacity to on-chain weight. The main practical challenge is coordination: all members must cooperate to update the factory, and the larger the group, the harder that becomes. Symmetric update schemes are seen as a key enabler for robust multi-party factories.
Channel factories pair naturally with Eltoo, whose symmetric state model eases the multi-party updates a factory requires.
In Simple Terms
A channel factory is a multi-party Lightning construction in which a group of users cooperatively lock their funds into a single on-chain multisignature output, then…