Lago is open-source billing infrastructure you host yourself. Commet is a managed billing platform that acts as your Merchant of Record.
Both handle usage-based billing well. The difference is who owns the operational burden.
TL;DR
| Lago | Commet | |
|---|---|---|
| Type | Open-source billing engine | Managed billing + MoR |
| Hosting | Self-hosted (or Lago Cloud) | Fully managed |
| Merchant of Record | No (you are the seller) | Yes (Commet is the seller) |
| Payment processing | BYO (Stripe, Adyen, etc.) | Included (Stripe under the hood) |
| Tax handling | Not included | Built-in (MoR handles it) |
| Usage-based billing | Strong metering and aggregation | First-class (metered, credits, balance) |
| LATAM support | No local focus | LATAM-first with 9+ local currencies |
| Pricing | Free (self-hosted), Lago Cloud free to $250K then 0.75%, Performance $599/mo | 4.5% + $0.40 per transaction |
Open Source vs Managed Service
Lago: you own the infrastructure
Lago gives you the billing engine and you run it. You deploy it on your infrastructure, maintain uptime, handle database backups, manage upgrades, and scale it as your transaction volume grows.
The upside is control. You see every line of code, you own your data completely, and you pay nothing for the software itself if you self-host. Lago has a strong developer community and transparent roadmap.
The downside is operational cost. Running billing infrastructure is not the same as running your product. Billing systems must be highly available, consistent, and auditable. Downtime in your billing engine means you cannot charge customers or check entitlements.
Commet: nothing to deploy
Commet is fully managed. There is no infrastructure to maintain, no upgrades to apply, no database to back up. You integrate via SDK, and Commet handles everything from metering to invoicing to payment collection.
The trade-off is less control over the underlying system. You depend on Commet's uptime and roadmap.
Payment Processing
Lago does not process payments. You connect your own payment processor (Stripe, Adyen, GoCardless) and configure the integration. Lago generates invoices, but collecting the money is your responsibility. This means managing payment failures, retries, and reconciliation yourself.
Commet includes payment processing through Stripe. When a customer checks out or an invoice is due, Commet collects the payment. Failed payment handling, retry logic, and reconciliation are built in.
Tax and Compliance
This is the biggest practical difference between the two.
Lago does not handle taxes. You calculate tax, collect it, remit it, and file returns. If you sell globally, that means registering in every jurisdiction where you have tax obligations, understanding local rules, and staying compliant as regulations change. For US sales alone, you may need to handle sales tax across 45+ states with different rates and rules.
Commet is a Merchant of Record. Commet is the legal seller. Tax calculation, collection, remittance, invoicing, and compliance are handled by Commet. You do not need to register for tax in any country. This is not a tax integration, it is a complete transfer of responsibility.
For a startup selling to customers in multiple countries, the difference between "integrate a tax API" and "someone else handles all of it" is hundreds of hours per year.
Usage-Based Billing Comparison
Both platforms take usage-based billing seriously. The approaches differ.
| Feature | Lago | Commet |
|---|---|---|
| Event ingestion | HTTP API with deduplication | SDK with real-time processing |
| Aggregation types | Count, sum, max, unique count, weighted sum | Metered, credits, balance |
| Real-time entitlements | No (batch processing) | Yes (query before action) |
| Credit systems | Prepaid credits with wallets | First-class credit packs |
| Balance accounts | Wallet with top-ups | Built-in balance model |
| Billing periods | Weekly, monthly, quarterly, yearly | Monthly, quarterly, yearly |
| Progressive billing | Yes (in-advance charges) | Hybrid (advance base + true-up usage) |
Lago is strong on aggregation flexibility. You can define complex metering rules with multiple aggregation types and filters. If your usage model requires custom aggregation pipelines, Lago gives you more configuration options.
Commet is stronger on real-time access control. Your application checks entitlements before a user takes an action, getting a deterministic answer about whether the user can proceed. No batch processing, no reconciliation delays.
Developer Experience
Lago provides a REST API, Ruby and Node.js client libraries, and a self-hosted dashboard. Configuration is code-driven through API calls. The open-source nature means you can read the source, contribute fixes, and understand exactly how billing calculations work.
Commet is SDK-first with embeddable components. Checkout and the customer portal embed directly in your application rather than redirecting to a hosted page. Entitlement checks are synchronous API calls, not webhook-driven state machines.
When to Choose Lago
- You want full control over your billing infrastructure and data
- Your team has the capacity to operate a self-hosted billing system
- You need complex aggregation pipelines for usage metering
- You already have payment processing and tax compliance handled
- You prefer open-source software and want to inspect or modify the code
- Budget predictability matters more than operational simplicity (self-hosted is free)
When to Choose Commet
- You want someone else to handle taxes, compliance, and payment collection
- You do not want to operate billing infrastructure
- Your product needs real-time entitlement checks
- You sell to LATAM customers and need local currency pricing
- You want checkout and billing portal embedded in your app
- You prefer paying per transaction over managing infrastructure costs
Final Thought
Lago gives you an open-source billing engine with full control and zero software cost. Commet gives you a managed billing service that handles payments, taxes, and compliance on your behalf.
The question is not which one has better billing features. The question is whether you want to own the operational burden of billing infrastructure and tax compliance, or pay a per-transaction fee to make it someone else's problem. See also how Commet compares to Stripe, Paddle, and Chargebee.