Lago's mark, an orange sphere, catches the light like a coin mid-spin - fitting for a company whose whole business is turning motion into money.
The open-source billing platform that turns raw usage into invoices - for the companies building the future.
Every software company eventually hits the same wall: it needs to charge customers, and the way it charges keeps changing. A flat monthly fee becomes per-seat, then per-usage, then a blend of credits, tiers and overages. Traditional billing systems either lock that logic inside a proprietary black box or force a team of engineers to build and babysit a homegrown one.
Lago, founded in Paris in 2021, takes a third path. It is an open-source billing and metering platform: software a company can read, fork and run on its own servers, or hand off to Lago's managed cloud. It ingests usage events in real time, aggregates them into billable quantities, and produces invoices for usage-based, subscription and hybrid pricing models.
The founders describe the core idea plainly - "if you can track it, you can bill for it." The metering engine supports seven aggregation methods and can handle up to a million events per second, which is why it keeps showing up inside AI and infrastructure companies whose pricing is measured in tokens, calls and gigabytes.
Customer names per Lago public materials
“Every company needs billing. Lago gives you the flexibility of a homegrown system with the features of an enterprise vendor.”— Lago, on why it exists
Co-founders Anh-Tho Chuong and Raffi Sarkissian were among the earliest employees at Qonto, the European B2B neobank, where they helped grow revenue from pre-product to Series D and built the monetization system that carried the company past $100M in revenue.
Along the way they watched something wasteful: at a major fintech, more than ten engineers worked full-time on billing alone. Pricing changes took months. Finance teams reconciled by spreadsheet. Billing, they realized, was a universal and badly under-served problem - and one they had already solved once by hand.
So in 2021 they left to build it for everyone, open source. Lago joined Y Combinator's Summer 2021 batch and began shipping.
When billing lives in a black box, the product team can't ship a new plan without an engineering project, and finance can't trust the numbers without manual checks. That friction quietly caps how fast a company can experiment with pricing - often the single biggest lever on revenue.
Lago's answer is to separate the metering layer (turning events into billable quantities) from payments, and to make that layer transparent and owned. Teams get progressive billing, coupons, credit notes, prorated charges and entitlements without writing them from scratch - and without per-transaction fees skimming their revenue.
From event ingestion to revenue analytics, Lago is assembled from modular pieces teams can adopt as they grow.
Real-time event ingestion with seven aggregation methods and multi-dimensional metering at up to 1M events/second.
Since 2021Automated, compliant invoices for usage, subscription and hybrid models - with coupons, credit notes and progressive billing.
Since 2021Feature-access control tied to billing plans, so what a customer can use maps to what they pay for.
2024Payment orchestration with dunning and automatic retries across providers to recover failed charges.
2023MRR tracking and revenue visibility built directly on top of your billing data.
2023An AI-powered billing intelligence layer aimed at complex, AI-native revenue models.
2025Lago runs on an open-core model. The Community edition is free and open source under AGPLv3, with no revenue caps and no per-event fees - genuinely free to self-host at any scale.
Two managed cloud tiers, Business and Enterprise, are quote-only. They add hosted infrastructure, support, compliance and premium add-ons. Revenue comes from those subscriptions and enterprise features, not from a cut of every transaction - a deliberate contrast with legacy billing vendors.
Anh-Tho Chuong and Raffi Sarkissian, both early Qonto employees, launch Lago and join Y Combinator's Summer 2021 batch.
SignalFire leads a $7M seed to build the open-source billing engine.
Mistral reaches out before launching its paid product and goes live on Lago within 52 days.
FirstMark Capital leads a $15M Series A, bringing total funding to $22M.
The platform expands into AI-native billing intelligence and white-label embedded billing.
Lago builds e-invoicing compliance engines for European mandates and restructures pricing into Business and Enterprise tiers.
“We raised $22 million to build an open-source alternative to traditional payments and billing platforms.”— Lago, Series A announcement, March 2024
Lago's $22M has come from FirstMark Capital, SignalFire and Y Combinator, with New Wave and a notable roster of operator-angels: Meghan Gill, who ran MongoDB's monetization for 14 years; Romain Huet, former head of developer relations at Stripe; and Clement Delangue, CEO of Hugging Face.
That angel list is telling - the people who have monetized developer products at scale are the ones betting on Lago's approach.
The shift to usage-based pricing has become the default for modern software, and the AI boom accelerated it: tokens, credits and inference don't fit neatly into "per seat, per month." Lago's event-streaming architecture was built for exactly that shape of billing.
As European e-invoicing mandates arrive - France first in 2026 - owning your billing stack becomes a compliance advantage, not just an engineering preference. That is the market Lago is positioned to serve.
Lago is an open-source billing and metering platform. It ingests usage events in real time and turns them into invoices, supporting usage-based, subscription and hybrid pricing models.
Yes - the self-hosted Community edition is free and open source under AGPLv3, with no revenue caps or per-event fees. Lago also offers paid managed cloud tiers (Business and Enterprise) with support and additional features.
Companies including Mistral AI, PayPal, Groq, Synthesia, Laravel and Swan use Lago to meter usage and issue invoices, collectively processing an estimated $800M+ in invoices per month.
Lago is open-source and can be self-hosted with full code ownership and no per-transaction fees, whereas Stripe Billing and Metronome are proprietary cloud services. That control appeals to teams that want to own their revenue infrastructure.
Lago was founded in 2021 by Anh-Tho Chuong (CEO) and Raffi Sarkissian (CPO), both early employees at the neobank Qonto, and is backed by FirstMark, SignalFire and Y Combinator.
Sources: getlago.com, github.com/getlago, TechCrunch, Crunchbase, Y Combinator, Sacra, Dealroom