Automate complex billing for professional services, from retainers and project fees to usage-based consulting hours.
Lago is an open-source billing platform that handles hybrid pricing models, giving your firm transparency and control.
What is Lago?
Lago: Automate complex billing for professional services, from retainers and project fees to usage-based consulting hours. It has a free plan. Zekai's independent review scores it 8.5 out of 10. Best for automating complex, hybrid billing for services firms.
Zekai Verdict
- What is it?
- Lago is an open-source, API-first billing platform designed for professional services firms with complex revenue models.
- Best for
- Best for professional services firms needing to automate and scale complex, hybrid billing models that mix retainers…
- Not ideal for
- Requires engineering resources for initial setup and integration.
- Price
- Free plan
- Zekai Score
- 8.5/10
Top AI for General (Professional Services) picks
See all 120 AI tools for Consultants →For professional services firms with complex client contracts, Lago is a leading AI-powered billing platform. Its strength lies in automating hybrid models that mix retainers, project fees, and usage-based billing, a common need in consulting and agencies. As an open-source, API-first solution with SOC 2 Type II compliance, it provides the flexibility and security required to manage sophisticated revenue streams.
Your workflow, automated
Before & After
Manually calculating and invoicing for complex, multi-part client contracts using spreadsheets.
Automated, accurate billing for any hybrid model, with a single source of truth for revenue.
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Lago integrations
Best Lago alternatives
**Lago vs. Stripe Billing**: Stripe Billing is excellent for straightforward subscription and metered billing, deeply integrated into Stripe's payment ecosystem. It's fast to set up for common use cases. Choose Stripe if your billing is relatively standard and you're already committed to its payment processing. Lago is the superior choice when billing logic becomes highly complex and non-standard. Its open-source, API-first nature allows for unparalleled flexibility to model any hybrid plan (e.g., retainers + multiple usage tiers + one-off fees), self-host for data control, and integrate with any payment provider, not just Stripe. Pick Lago for maximum control and complexity.
Is Lago worth it?
Why General (Professional Services) choose this tool
Key Use Cases
Lago is a powerful, developer-friendly solution for professional services firms that have outgrown simple invoicing tools. Its strength is its flexibility in handling any conceivable billing logic, from metered consulting hours to multi-product retainers. The main trade-off is its complexity; it requires engineering resources to implement and is not an out-of-the-box solution for simple billing.
Frequently asked questions
What kind of billing models can Lago handle for a consulting firm?
Is Lago suitable for a non-technical operations team?
Can Lago be deployed on our own servers?
How does Lago ensure data security for client billing information?
Does Lago integrate with accounting software like QuickBooks or Xero?
What is the best AI billing tool for a professional services firm with complex contracts?
Last reviewed:
Lago pricing and plans
Prices and features are updated regularly but can change at any time — always confirm on the official website. Some links on this page are affiliate links.
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Take it with you
- Map Your Service Contracts to Lago's Models
- Understand Usage Metering for Billable Hours
- Connect Your CRM and Time-Tracking Tools
- Automate Invoicing & Dunning
- Leverage Revenue Analytics for Client Insights
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About Lago
Full Description
Lago is an open-source, API-first billing platform designed for professional services firms with complex revenue models. It automates invoicing for hybrid structures like subscriptions, usage-based fees, and custom enterprise contracts. This gives finance and operations teams a single, transparent system for all billing data.
Editorial Verdict
Lago is a powerful, developer-friendly solution for professional services firms that have outgrown simple invoicing tools. Its strength is its flexibility in handling any conceivable billing logic, from metered consulting hours to multi-product retainers. The main trade-off is its complexity; it requires engineering resources to implement and is not an out-of-the-box solution for simple billing.
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