Definition
A zero-confirmation (zero-conf) channel is a Lightning Network payment channel that can send and receive immediately after its funding transaction is broadcast, before that transaction is mined into a block. Normally a node waits several confirmations to be sure the funding transaction cannot be reversed; a zero-conf channel skips that wait so a user can transact instantly. This is what enables the "turbo" onboarding many mobile wallets advertise.
The trust trade-off
Skipping confirmations reintroduces a small, bounded trust assumption. The party accepting the channel (the fundee) must trust the opener (the funder) not to double-spend the funding transaction before it confirms and thereby steal the channel's balance. That trust window lasts only until the funding transaction is mined, typically one to a few blocks. For this reason zero-conf is normally accepted only from a known, reputable counterparty, most often a Lightning Service Provider opening a channel to its own user, rather than between arbitrary strangers.
How it is enabled
Zero-conf is formalized in the Lightning specification through the option_zeroconf feature bit, and when it is in use the channel's required minimum confirmation depth is set to zero. It works alongside short channel ID aliases, which give the not-yet-confirmed channel a usable identifier for routing until its real on-chain ID exists. Some setups add a third-party co-signer to further reduce double-spend risk.
Zero-conf channels are a staple tool of a Lightning Service Provider, letting new users receive payments the moment their wallet is set up. D-Central also covers turbo channels in depth in its Lightning guides.
In Simple Terms
A zero-confirmation (zero-conf) channel is a Lightning Network payment channel that can send and receive immediately after its funding transaction is broadcast, before that transaction…