Phoenix

What is Phoenix?

Phoenix is a wallet for the Lightning NetworkGlossaryLightning NetworkA second layer on top of Bitcoin for fast, low-cost payments. Amounts move off the blockchain via payment channels; only opening and closing a channel ends up in a block as a normal transaction.On the learning path: Stage 1 · Step 3 – How does Bitcoin work? →In the glossary →×, developed by ACINQ in Paris ^[1]. The app is available for iOS and Android and is open source under the Apache 2.0 licence ^[2]. It is a self-contained Lightning node on your smartphone, and you hold the keys yourself ^[3].

You do not have to manage channels: since 2023, each user has just one channel to ACINQ, which grows as needed through ‘splicing’ ^[4]. You can also send and receive regular on-chain payments; Phoenix handles them in the background via your Lightning channel ^[3]. How Lightning works is explained in The Lightning Network.

Costs (as of September 2026)

Action	Fee
Sending via Lightning	0.4% + 4 sats
Receiving via Lightning	no fee, as long as there is room in the channel
Receiving without enough capacity	1% + mining fee
Requesting receiving capacity in advance	1% + mining fee
Channel opening	one-off 1,000 sats
Sending or receiving on-chain	mining fee (you choose it when sending)

Your first deposit opens your channel: on top of the mining fee (plus 1% if it arrives via Lightning) comes a one-off 1,000 sats. If the fee is above 5,000 sats or more than half the amount, Phoenix rejects the payment by default; you can change this limit in the settings ^[3]. Very small first deposits are therefore not worth it. For scale: $1 is currently around 1,169 sats.

Security and custody

During setup, Phoenix generates a 12-word recovery phrase. Only you have it – if it is lost, your funds are lost ^[2]. Keep it offline like any seed phraseGlossarySeed phrase (recovery phrase)A sequence of usually 12 or 24 words from which your wallet derives all its private keys. Anyone who knows the words has full access to your bitcoin – so they belong in an offline backup and never in anyone else’s hands.On the learning path: Stage 5 · Step 3 – Backing up your seed phrase →In the glossary →×. Do not use it in two Phoenix apps at the same time, or channels may be closed ^[3].

Phoenix is a hot walletGlossaryHot walletA wallet whose private keys are stored on a device connected to the internet – such as a smartphone app. Handy for payments and small amounts, but more exposed to online attacks than cold storage.On the learning path: Stage 5 · Step 1 – Understanding custody →In the glossary →× on an internet-connected smartphone: practical for everyday amounts, but for savings a hardware walletGlossaryHardware walletA small dedicated device that keeps your private keys offline and signs transactions internally. The key never leaves the device, so malware on your computer can’t get at it.On the learning path: Stage 6 · Step 1 – Hardware wallets compared →In the glossary →× is safer.

What to watch out for

• Privacy: according to ACINQ, Phoenix currently offers no privacy advantage over custodial wallets. ACINQ knows the destination and amount of your payments ^[3].
• Some trust remains: if your channel is opened or enlarged by an incoming Lightning payment, you trust ACINQ until the transaction is confirmed on the blockchain ^[3].
• Reliance on ACINQ: if ACINQ disappears, your funds stay safe, but Lightning payments no longer work. You then close your channel unilaterally; after 720 blocks (around 5 days) your funds are back on the blockchain. This costs high fees and is meant only for that emergency ^[3].