Lightning Service Provider Comparison: LSPs for Wallets and Apps

Lightning Service Providers Overview

A Lightning Service Provider (LSP) handles the infrastructure that makes Lightning Network payments work for end users: opening payment channels, providing inbound liquidity, managing channel state, and routing payments. Without an LSP, every wallet user would need to run their own Lightning node and manually source liquidity, which is impractical for mobile apps and non-technical users.

The LSP landscape has shifted significantly in 2025 and 2026. Breez deprecated its Greenlight SDK in favor of Liquid-based swaps and a new Spark integration. Voltage deprecated its Flow 2.0 LSP product. Mutiny Wallet shut down entirely. Meanwhile, institutional adoption accelerated with Coinbase, Nubank, and SoFi integrating Lightning through Lightspark. The market is consolidating around a few approaches: swap-based (Breez SDK Liquid), channel-based with splicing (ACINQ Phoenix), modular libraries (LDK), managed enterprise platforms (Lightspark), and Layer 2 protocols like Spark that bypass traditional channel management altogether.

SDK and Language Support

Language support determines which developer teams can realistically integrate a given LSP or Lightning library. The following table compares SDK availability across providers. LDK and Breez SDK offer the broadest language coverage, while ACINQ's Kotlin Multiplatform approach targets mobile-first development.

Breez SDK

Breez SDK is the most widely integrated Lightning SDK, powering over 75 apps including Cake Wallet, Deblock, and Klever. In 2025, Breez deprecated its Greenlight implementation (which ran CLN nodes via Blockstream's cloud infrastructure) and shifted to two new backends: Liquid and Spark.

The Liquid implementation uses submarine swaps via Boltz exchange infrastructure to move between the Liquid sidechain and Lightning. This eliminates traditional Lightning channel management entirely. Users hold funds on Liquid and swap into Lightning only when sending or receiving payments. Send fees are 0.1% plus approximately 53 sats in on-chain costs. Receive fees are 0.25% plus approximately 47 sats.

The Spark implementation, announced in May 2025, builds on Spark as a Bitcoin-native Layer 2. It is still in beta (Python package v0.6.6 as of January 2026) but represents Breez's direction toward nodeless Lightning-compatible payments without channel or sidechain dependencies.

LDK: Lightning Dev Kit

LDK is a modular Rust library developed by Spiral (a subsidiary of Block) that provides the building blocks for a custom Lightning implementation. Unlike Breez or ACINQ, LDK is not a turnkey solution: it gives developers full control over channel management, storage, networking, and chain data sourcing. LDK Node (v0.7.0, December 2025) provides a higher-level wrapper for teams that want a ready-to-go node without assembling every component from scratch.

LDK v0.7.0 added splicing support and async payments. The lightning-liquidity crate implements LSPS2 for zero-conf JIT channel support, allowing LDK-based wallets to connect to any LSPS2-compliant LSP.

Notable LDK users include CashApp (which processes Lightning payments for millions of users), Alby Hub, and previously Mutiny Wallet. The tradeoff is development effort: LDK requires significantly more engineering time than an integrated SDK like Breez, but offers unmatched flexibility for teams building differentiated Lightning products.

ACINQ and phoenixd

ACINQ operates the Lightning Service Provider behind Phoenix Wallet and offers phoenixd as a server-side daemon for developers. ACINQ's key innovation is splicing: instead of opening and closing multiple channels, Phoenix maintains a single dynamic channel that resizes via on-chain splice transactions. This simplifies the user experience and reduces the on-chain footprint.

As of Phoenix v2.4.0 (October 2024), ACINQ moved from a proprietary LSP protocol to an open standard based on dual funding, splicing, and liquidity ads. Send fees are a flat 0.4% (including routing). Receive fees cover only the mining cost of the splice transaction: when the mempool is empty, a deposit can cost as little as 300 sats.

phoenixd (v0.7.3, March 2026) provides an HTTP API for server-side integration. It handles all channel and liquidity management automatically, making it suitable for merchants, crowdfunding platforms, and any application that receives frequent Lightning payments. The main limitation is vendor dependency: ACINQ is the sole LSP for Phoenix and phoenixd.

Lightspark

Lightspark is the enterprise-focused Lightning platform, built for regulated financial institutions. Its Connect product provides fully managed Lightning nodes with an AI-powered routing engine called Predict that optimizes payment success rates. Lightspark's Grid product (launched 2026) offers a single API for fiat, stablecoins, and Bitcoin, including branded USD accounts, Visa debit cards, and payouts to 65+ countries and 14,000 banks.

Lightspark also developed the Universal Money Address (UMA) protocol, which extends Lightning Addresses with cross-currency payment messaging and built-in travel rule compliance. UMA SDKs are available in Go, Rust, TypeScript, Python, and Kotlin.

Notable customers include Coinbase (which routes 15% of BTC transactions via Lightning through Lightspark), Nubank (100M+ customers in Latin America), and SoFi (the first US bank to integrate Lightning and UMA for remittances). Pricing is enterprise-tier and not publicly listed. Lightspark also developed the open-source Spark protocol, a Bitcoin Layer 2 that supports stablecoins and Lightning-compatible payments.

Voltage

Voltage provides managed LND node hosting with enterprise-grade infrastructure, monitoring (Surge Analytics), and encrypted key management. However, Voltage deprecated its Flow 2.0 LSP product in September 2024, meaning it no longer offers JIT channel provisioning for wallets. As of May 2026, Voltage has not announced a replacement LSP service.

Voltage remains relevant for teams that want to run their own LND nodes without managing hardware. In February 2026, Voltage launched Voltage Credit: a USD-settled revolving line of credit for Lightning businesses at 12% APR with revenue-based underwriting. This positions Voltage more as a financial infrastructure provider than a direct LSP.

Olympus by ZEUS

Olympus is the LSP operated by the ZEUS team for the ZEUS self-custodial wallet. It provides zero-conf JIT channels with a tiered fee structure: payments under 20 sats incur a 50% fee, payments under 2,500 sats incur 10%, and payments above 2,500 sats pay a flat 250 sat fee. Pre-purchased channels via LSPS1 cost 6,000 to 10,000 sats for setup depending on size, with selectable lifetimes from two weeks to twelve months. Total capacity is capped at 10M sats across all Olympus channels.

Olympus charges zero routing fees on the first hop, and ZEUS Pay lightning addresses are free for receivers. Olympus also integrates with Alby Hub via the LSPS1 standard, allowing users of other wallets to purchase channels from Olympus directly.

LSP Specifications (LSPS)

The LSP Specification project defines open standards for wallet-LSP interoperability. The goal is to allow any wallet to connect to any compliant LSP without vendor lock-in. Key specifications include:

• LSPS1: channel request protocol for pre-purchasing inbound liquidity
• LSPS2: JIT (just-in-time) channel creation, the most widely implemented spec
• LSPS4: continuous JIT channels for ongoing liquidity management
• LSPS5: webhook notifications for asynchronous event delivery

LDK's lightning-liquidity crate provides a Rust implementation of LSPS2 (currently in alpha). Olympus and Alby Hub both support LSPS1. ACINQ has moved to an open protocol based on dual funding, splicing, and liquidity ads rather than the LSPS specifications directly. Adoption remains uneven, but the trend is toward interoperability.

How to Choose an LSP or Lightning SDK

The right choice depends on your team's resources, your product's requirements, and your custody model.

If you need the fastest path to a working Lightning wallet with minimal engineering effort: Breez SDK (Liquid) is the most battle-tested option, with 10 language bindings and over 75 production apps. The swap-based model eliminates channel management entirely.

If you need full control over Lightning behavior and are building a differentiated product: LDK gives you modular components to assemble a custom implementation. Expect a larger engineering investment but unmatched flexibility.

If you are building a server-side application that receives many Lightning payments (merchant, crowdfunding, tipping): phoenixd offers automatic liquidity management with a simple HTTP API. The 0.4% send fee and splice-based receive model keep costs predictable.

If you are a regulated financial institution or need enterprise compliance features: Lightspark Connect provides managed infrastructure with OFAC screening, travel rule support via UMA, and audit-ready reporting. The platform is custodial.

If you want to explore Bitcoin-native approaches beyond traditional channels: the Spark protocol enables Lightning-compatible payments without channel management, and Breez SDK's Spark implementation is building toward SDK-level access. For a broader view of wallet SDK options, including non-Lightning approaches, see our dedicated comparison.

Frequently Asked Questions

What is a Lightning Service Provider?

A Lightning Service Provider (LSP) is an entity that manages Lightning Network infrastructure on behalf of wallet users. LSPs open and manage payment channels, provide inbound liquidity so users can receive payments, and route transactions across the network. Without an LSP, each user would need to run their own Lightning node, fund channels, and manage liquidity manually. For a deeper look at how LSPs work, see our LSP explainer.

Which Lightning SDK is best for mobile wallet development?

Breez SDK (Liquid) is the most commonly chosen option for mobile wallets due to its broad language support (Kotlin, Swift, React Native, Flutter), swap-based architecture that eliminates channel management, and production track record across 75+ apps. LDK also supports Kotlin and Swift but requires more engineering effort to integrate. ACINQ's lightning-kmp library is Kotlin Multiplatform and powers the Phoenix wallet but is less commonly used by third-party developers.

How much does it cost to use a Lightning Service Provider?

Costs vary significantly by provider. Breez SDK charges 0.1% to send and 0.25% to receive, plus small on-chain fees (roughly 50 to 100 sats per transaction). ACINQ/phoenixd charges 0.4% for sends and only mining fees for receives. Olympus by ZEUS charges a flat 250 sats for payments above 2,500 sats. Lightspark uses enterprise pricing with tiered platform fees. LDK itself is free, but you must source and pay for your own liquidity.

What happened to Mutiny Wallet and Voltage Flow LSP?

Mutiny Wallet ceased operations at the end of 2024 and was removed from app stores on December 31, 2024. The team pivoted to other projects. Voltage deprecated its Flow 2.0 LSP product in September 2024, stopping new channel creation and beginning channel closures in November 2024. Voltage continues to offer managed LND node hosting but has not announced a replacement LSP service. These exits reflect the difficulty of operating a sustainable LSP business.

What is the difference between a Lightning SDK and an LSP?

An LSP is a service that provides liquidity and channel management. An SDK is a developer toolkit for building Lightning-capable applications. Some products combine both: Breez SDK bundles an SDK with access to Breez's swap infrastructure. LDK is purely a library with no bundled LSP. phoenixd is closer to a self-contained LSP client that connects exclusively to ACINQ's node. The distinction matters because SDKs can often be paired with different LSPs, while some solutions lock you into a specific provider.

Can I switch between Lightning Service Providers?

It depends on your implementation. The LSPS specifications aim to make LSP-switching possible by standardizing the wallet-LSP interface: if your wallet supports LSPS1 or LSPS2, you can theoretically connect to any compliant LSP. In practice, most current integrations are tightly coupled to a specific provider. Breez SDK locks you into Breez's infrastructure. Phoenix is tied to ACINQ. LDK-based wallets have the most flexibility since they can implement LSPS2 and connect to multiple LSPs.

How does Spark compare to traditional Lightning LSPs?

Spark is a Bitcoin Layer 2 protocol that provides Lightning-compatible payments without traditional channel management. Unlike LSPs that open and manage payment channels on your behalf, Spark uses a statechain-based architecture where users hold Bitcoin directly without locking funds into channels. Payments are Lightning-compatible, meaning Spark users can send to and receive from any Lightning wallet. This eliminates the need for inbound liquidity provisioning, channel rebalancing, and the on-chain fees associated with channel opens and closes.

This tool is for informational purposes only and does not constitute financial advice. Data is approximate and based on publicly available information as of May 2026. Pricing, features, and availability change frequently. Always verify current data with each provider before making integration decisions.