9 Best Usage-Based Billing Software for PLG SaaS
The quick answer
Quick answer: if you already take payments on Stripe, Stripe Billing costs 0.7% of billing volume and includes basic metering, while Metronome, now part of Stripe, is the deeper usage engine (its Startup plan bills 0.8% of billing volume plus $0.04 per 1,000 ingested events). Chargebee has a pay-as-you-go Flow plan from $0 a month plus 0.80% of invoicing volume, with 100M usage events a month included. Schematic is free up to $5K a month in billing volume and adds in-product entitlements and credits. For open source, Lago (AGPL-3.0) and OpenMeter (Apache 2.0, now owned by Kong) can be self-hosted. Orb suits teams with heavy event volumes and custom contracts, and Polar bundles usage billing with merchant of record services. Prices are as of October 2026, checked on each vendor's own site.
What usage-based billing software does
Usage-based billing software turns product activity into invoices. It ingests usage events (API calls, tokens, seats, storage), aggregates them into billable metrics, applies a price (per unit, tiered, volume, prepaid credits) and produces an invoice or charge. For a product-led SaaS company, four things matter most:
- Free tiers and limits: the tool should track included usage on a free plan and tell your product when a user hits the limit, so the upgrade prompt fires at the right moment.
- Self-serve upgrades: plan changes, credit top-ups and proration should work without a sales rep.
- Spend visibility: customers on metered plans want to see usage and cost before the invoice arrives.
- Pricing changes without code: you will change packaging more than once, so versioning and migrations matter.
Also check how the vendor charges you. Most tools in this list take a percentage of the revenue billed through them, some add a per-event fee, and merchant of record tools take a larger cut because they also handle sales tax. If you are still deciding on a model, our guide to pricing strategy for product-led growth covers the trade-offs.
Usage-based billing software compared
| Tool | Best for | Open source | Free or entry option | Paid pricing (as of October 2026) |
|---|---|---|---|---|
| Stripe Billing | Teams already on Stripe | No | Pay as you go | 0.7% of billing volume |
| Metronome | Usage-heavy and AI products | No | Startup plan, self-serve | 0.8% of billing volume plus $0.04 per 1K events |
| Orb | High event volumes, custom contracts | No | Demo | Custom (billings and events) |
| Lago | Self-hosted usage billing | Yes, AGPL-3.0 | Self-host the open-source code | Premium on request |
| Chargebee | Hybrid subscription plus usage | No | Flow at $0 a month | 0.80% of invoicing volume, or $99 plus 0.65% |
| Schematic | Entitlements and credits in product | No | Free to $5K a month billed | Growth $400 a month |
| OpenMeter (Kong) | Metering for APIs and AI | Yes, Apache 2.0 | 30-day Konnect trial | $20 per 1M events; 0.4% of billing volume |
| Polar | Indie and early-stage teams wanting a MoR | Yes, Apache 2.0 | Starter, no monthly fee | 5% + 50¢ per transaction |
| Maxio | Finance-led B2B SaaS | No | Demo | Grow $599 a month |
1. Stripe Billing
Who it is for: teams that already process payments with Stripe and want subscriptions, trials and basic metering in one account.
Pricing: pay as you go at 0.7% of Billing volume, which covers Billing transactions processed on and off Stripe and excludes one-off invoices. A custom domain for the customer portal is US$10 a month. Payment processing is charged separately.
Strengths: subscriptions, trials, discounts, Smart Retries, a hosted customer portal, quotes and subscription schedules. Basic usage-based billing through the Meters API stays part of Billing pricing, with up to 100M events a month included.
Limits: Stripe's own usage-based billing docs now tell new integrations to use Metronome for most usage-based cases unless they already run on Billing Meters, so the native meters are best for simple models.
2. Metronome
Who it is for: usage-heavy and AI products that need real-time metering, credits and both self-serve and enterprise contracts on one system.
Pricing: the Startup plan bills 0.8% of billing volume plus $0.04 per 1,000 ingested events. A Custom plan adds Salesforce, NetSuite and cloud marketplace invoicing, warehouse exports and a dedicated account manager. Source: Metronome pricing.
Strengths: SQL-based billable metrics, streaming alerts, rate cards, commits and credit models, per-customer contract overrides and embeddable billing dashboards. Metronome's blog states that its acquisition by Stripe is complete, and Stripe now lists it as its usage-based billing product.
Limits: two fees (billing volume and events) to model, and the deepest integrations sit on the Custom plan.
3. Orb
Who it is for: companies with large event volumes or complex contracts where billing errors are expensive.
Pricing: Core, Advanced and Enterprise are all custom pricing. Orb says pricing is based on billings and events, and Advanced and Enterprise add a platform fee. Source: Orb pricing.
Strengths: raw-event ingestion with custom SQL metrics, real-time alerts, threshold billing, prepaid credits, price versioning and migrations, and an experience kit for pricing calculators and usage dashboards. Every plan includes Orb Invoicing plus QuickBooks, Stripe and tax integrations.
Limits: no public prices or self-serve start; Salesforce and NetSuite integrations need Advanced.
4. Lago
Who it is for: engineering teams that want to own their billing stack or must keep usage data in their own infrastructure.
Pricing: the core is open source under AGPL-3.0 on GitHub and free to self-host. Lago Premium, available in the cloud or self-hosted, is priced on request. Source: Lago pricing.
Strengths: usage metering, hybrid and prepaid credit plans, wallets with alerts, entitlements, a customer portal and plan overrides per customer. Lago can be deployed on-prem or in a VPC.
Limits: several features, including progressive billing, tax integrations and automatic dunning, are listed as add-ons, and self-hosting means you run the infrastructure.
5. Chargebee
Who it is for: SaaS teams that bill a mix of seats, plans and usage and want trials, checkout and retention tools from one vendor.
Pricing: Flow is pay as you go, either $0 a month plus 0.80% of monthly invoicing volume or $99 a month plus 0.65%, and includes 100M usage events a month. Enterprise (up to 500M events, multi-entity, account hierarchies) is by demo. Source: Chargebee pricing.
Strengths: metered or real-time event ingestion with custom SQL meters, included usage per plan, usage thresholds and overages, pricing tables, hosted checkout and a self-serve portal. Chargebee also markets a product-led motion with free trials and in-app upgrades.
Limits: NetSuite, Salesforce and Avalara AvaTax integrations are not included in Flow. See our Chargebee alternatives for other options.
6. Schematic
Who it is for: PLG teams whose main problem is enforcing plan limits, credits and feature access inside the product.
Pricing: Starter is free and covers the whole platform up to $5K a month in billing volume, with two custom plans and email support. Growth is $400 a month with up to 15 custom plans, 20 overrides and a dedicated billing engineer in Slack. Enterprise is priced on billing volume or a flat rate. Schematic says it charges nothing extra for event ingestion. Source: Schematic pricing.
Strengths: usage-based billing with entitlements enforced by company, user or agent, a credit ledger, plan versioning and in-product usage and wallet components. If you gate features with flags today, compare it with the tools in our feature flag tools roundup.
Limits: the free plan caps billing volume and custom plans, so it is a starting point rather than a long-term free option.
7. OpenMeter (Kong Konnect Metering & Billing)
Who it is for: API and AI products that want open-source metering, or teams already on Kong.
Pricing: OpenMeter's code is Apache 2.0. Kong acquired OpenMeter in September 2025, and OpenMeter Cloud is now Konnect Metering & Billing. Kong's pricing page lists metering at $20 per million ingested events and billing at 0.4% of billing volume, with Plus limits of 10M events and $250,000, and volume discounts on Enterprise. Konnect has a 30-day free trial. Source: Kong pricing.
Strengths: real-time metering for APIs and AI usage, entitlements and quota enforcement, and a no-code product catalog for pricing changes.
Limits: the hosted product now sits inside Kong's API platform, which is more than most SaaS teams need for billing alone.
8. Polar
Who it is for: indie developers and early-stage SaaS teams that want usage billing and tax handling in one place.
Pricing: Starter has no monthly fee and charges 5% + 50¢ per transaction. Pro ($20 a month, 3.8% + 40¢), Growth ($100 a month, 3.6% + 35¢) and Scale ($400 a month, 3.4% + 30¢) lower the rate. International cards add 1.5%. Source: Polar fees page.
Strengths: Polar acts as merchant of record, and its docs cover usage-based billing, seats, credits, a customer portal and an MCP server. The code is Apache 2.0 on GitHub.
Limits: a percentage of every transaction costs more than a billing-only tool at higher revenue. For other merchant of record options, see our Paddle alternatives.
9. Maxio
Who it is for: finance-led B2B SaaS teams that want billing, revenue recognition and SaaS metrics together.
Pricing: Grow is $599 a month for up to $100k in monthly billings; Scale (over $100k) is quote-based. Default agreements are paid annually. Source: Maxio pricing.
Strengths: every plan includes usage-based billing, subscription management, collections and dunning and 20+ payment gateways, and the platform adds metering, revenue recognition and SaaS metric reports, some only on Scale or as optional modules.
Limits: built for finance teams rather than developer-first self-serve, and annual contracts by default.
Tools we left out or would use with care
m3ter says it is now part of Salesforce (Salesforce announced the agreement on June 11, 2026) and describes its pricing as built for mid-size and large B2B SaaS companies, with no public prices. Amberflo has a 30-day free trial, but its pricing page currently mixes AI gateway request tiers with billing-volume tiers, so confirm the plan with the vendor. Zuora has no public pricing page and targets enterprise quote-to-cash.
How to choose usage-based billing software
Start with your payment rail. If you are on Stripe and your pricing is simple, Stripe Billing is the shortest path; if usage is the core of your revenue, look at Metronome, Orb or Chargebee. If you must self-host, Lago and OpenMeter are the open-source options. If you sell globally and do not want to register for sales tax, a merchant of record such as Polar removes that work at a higher fee.
Then model your real numbers: monthly billing volume, events per month and how often you change pricing. Billing tools only charge for usage; getting free users to the point where they need more still happens in the product. Our guide to freemium conversion rate covers that side, and tools like PLG OS add onboarding flows and in-app surveys around the upgrade moment.
FAQs
What is the best usage-based billing software for startups?
For teams on Stripe, Stripe Billing (0.7% of billing volume) or Metronome's Startup plan (0.8% plus $0.04 per 1,000 events) are the quickest starts. Schematic is free up to $5K a month in billing volume, and Chargebee Flow starts at $0 a month plus 0.80%.
Is there open-source usage-based billing software?
Yes. Lago is open source under AGPL-3.0 and OpenMeter under Apache 2.0, and both can be self-hosted. Polar's code is also Apache 2.0.
Is Metronome part of Stripe?
Yes. Metronome's blog states that its acquisition by Stripe is complete, and Stripe's docs recommend Metronome for most new usage-based integrations.
How do usage-based billing tools charge?
Most take a percentage of the revenue billed through them, such as 0.7% for Stripe Billing or 0.80% for Chargebee Flow. Metronome and Kong also charge per ingested event, and Orb prices on billings and events by quote.