Kill Bill pricing

About

Kill Bill is the leading open-source subscription billing & payments platform — a self-hostable engine for catalogs, subscriptions, invoicing, payments and usage metering. It has been on GitHub since roughly 2010 (5.6k+ stars), is licensed Apache-2.0, and ships with Kaui, a back-office admin UI for customer-success, finance, RevOps and developer teams. The core proposition is control and no lock-in: “Launch on open source. Add enterprise tooling when you need it. Deploy in your infrastructure, keep your data.”

Crucially, the engine itself is free. There is no per-usage meter and no percentage of your revenue on the open-source platform — you run it on your own infrastructure and pay only for the servers. Commercial revenue comes from three optional, modular layers stacked on top: the operating model (Self-Hosted Open Source for free, an AWS Marketplace deploy at a ~$40/mo software fee plus your AWS cost, or a fully-managed Hosted Platform run by a separate company, ChaChing); Aviate enterprise software tiers; and flat-annual-fee support. The whole pitch is that these fees are flat and predictable, deliberately decoupled from how much you bill.

For the most current information, visit Kill Bill.

Pricing summary : How Kill Bill’s pricing model works

Kill Bill frames pricing as “three decisions, one billing platform.” First, choose your operating model: Self-Hosted Open Source is Free (your data, your cloud, your compliance); AWS Marketplace runs in your AWS account for a ~$40/mo software fee plus your AWS infrastructure cost; or the Hosted Platform, fully managed by ChaChing, follows a separate commercial model (quoted). For customer-managed deployments, two further decisions follow.

Second, pick an Aviate capability level — a cumulative software ladder (each tier includes the one below): Entourage (Foundation: admin/account/billing-config workspace), Growth (Billing Core: dynamic catalog, pricing rules, usage metering via the Aviate plugin), Flock (Commercial Ops: quote/order/contract workflows + operational BI), and Finance (Finance-Grade: revenue recognition, accounting periods, SSP allocation, multi-entity governance). Aviate is software, not a support plan.

Third, add support — a separate purchase, always a flat annual fee, never tied to your revenue: Launch Support (onboarding/architecture review, up to 8 hours/month, best-effort, typical fit $2M–$10M ARR), Growth Support (up to 4 hours/week, typical fit $10M–$50M ARR), and Enterprise Support (priority queue, 48-hour SLA for critical issues, typical fit $50M+ ARR).

What makes this different: Kill Bill’s monetization is explicitly NOT a percentage of revenue and NOT a per-transaction meter — the two dominant models among SaaS billing vendors. The free open-source core plus flat-fee software/support means a customer’s cost stays flat as they scale, which the pricing page sells directly with a savings calculator.

Pricing by product

Sales motions across products: self-serve for the free open-source engine and the ~$40/mo AWS Marketplace deploy (download or launch and run it yourself), and sales-led for Aviate software tiers, support contracts, and the ChaChing Hosted Platform — all of which route through “Talk to the team” / “Contact Us” with quoted, scope-based pricing.

Hidden costs : What Kill Bill users actually pay

The headline “free” is genuine — the engine has no license fee, no usage meter, and no revenue share — but a self-hosted billing system still carries real total cost of ownership. The honest line items are your own infrastructure (servers, database, monitoring), the engineering time to deploy, operate and upgrade the stack, and — once billing becomes business-critical — the optional Aviate tooling and a support contract so you are not the only line of defense when invoices are wrong.

These figures come from Kill Bill’s own savings calculator (the slider example at $25M ARR), so treat them as the vendor’s representative package rather than a fixed price list — the per-tier Aviate and support fees are quote-stage and depend on scope. The point the calculator makes is the shape, not the exact number: against a typical competitor charging ~0.7% of revenue (about $175k/yr at $25M ARR), the flat package is roughly $110k+ cheaper — and because Kill Bill’s fees do not rise with revenue, that gap widens as you scale. The real “hidden” cost is therefore operational: you are buying control and predictable fees in exchange for owning the infrastructure and ops burden.

Want to estimate your own Kill Bill bill? Use the Kill Bill pricing calculator to model infrastructure plus Aviate and support against a percentage-of-revenue competitor.

Pricing evolution : Kill Bill pricing history and changes

Cadence

Tracked range: ~2010–present. Kill Bill publishes no per-tier price list for Aviate or support (those are quote-stage), so the timeline anchors on the open-source launch, the productization of Aviate + flat-fee support, and the live 2026-06-10 pricing-page capture.

Notable changes

• ~2010 — Kill Bill launches as a free, Apache-2.0 open-source billing & payments engine; the core has been free to self-host ever since, with no usage meter or revenue share.
• 2024–2025 — The commercial layer is productized into modular add-ons: Aviate software tiers, flat-annual-fee support plans, and an AWS Marketplace deploy (~$40/mo software fee) — explicitly decoupled from customer revenue.
• 2026-06-10 — The pricing page presents the “three decisions” model (operating model · Aviate software · support) and a savings calculator showing ~$50k–$75k/yr at $25M ARR versus ~$175k for a 0.7%-of-revenue competitor; the fully-managed Hosted Platform is run by ChaChing under a separate commercial model.

What’s unique : Kill Bill’s distinctive pricing mechanics

1. Free open-source core — no usage meter, no revenue share.

The entire billing engine is free under Apache-2.0. Unlike Stripe Billing or Chargebee, there is no percentage of billed revenue and no per-transaction fee on the platform itself — you pay only your own infrastructure. Monetization is pushed entirely to optional tooling and support.

2. Pricing deliberately decoupled from revenue.

Every paid layer — Aviate software and support — is a flat fee priced by scope/capability, “never tied to your revenue.” The pricing page literally ships a slider to prove that a flat package beats a 0.7%-of-revenue competitor by a growing margin as ARR rises.

3. Three orthogonal decisions, not bundled editions.

Operating model, Aviate software tier, and support level are sold as three independent choices, not packaged plans. A team can run the free engine with no support, or buy Aviate Finance with no support, or add Enterprise Support to a low Aviate tier — software and support are scoped and priced separately.

4. Cumulative software ladder.

Aviate tiers (Entourage → Growth → Flock → Finance) are cumulative — each includes everything below it — so the upgrade path mirrors billing maturity, from admin tooling through catalog/metering and quote-to-cash up to finance-grade rev-rec and multi-entity governance.

Strengths & weaknesses

Billing UX : Kill Bill billing controls and transparency

• Billing controls — Because the core is self-hosted, you control everything: catalog, pricing rules, invoicing and payment routing run on your own infrastructure via the open-source engine, with Kaui as the back-office admin UI. The commercial “controls” are which Aviate tier and support level you license — each a separate, scope-based purchase.
• Usage visibility — Kill Bill supports usage metering (the Growth/Billing-Core Aviate tier adds a metering plugin and dynamic catalog), but that is about metering your customers, not metering you — there is no spend dashboard for what you owe Kill Bill, because the engine fee is $0 and Aviate/support are flat annual fees.
• Payment options — Self-serve to start (download the open-source engine, or launch the ~$40/mo deploy on AWS Marketplace). Aviate software, support contracts (quarterly or annual), and the ChaChing Hosted Platform are invoiced under quoted commercial terms; Kill Bill does not publish a self-serve price list for those.

Strategic wins : Why Kill Bill’s pricing decisions worked

1. Free open-source core as the top of funnel

Giving away the engine under Apache-2.0 built 15+ years of adoption and 5.6k+ GitHub stars, creating a large base of self-hosting teams who can later buy Aviate tooling and support — a classic open-core land-and-expand. See how AI companies structure pricing.

2. Flat fees as a wedge against % of revenue

By refusing to charge a percentage of revenue or per-transaction fees, Kill Bill turns its pricing into a direct competitive weapon — the savings calculator makes the “you keep your upside as you scale” argument explicit. Related: choosing the right usage metric.

3. Modular, decoupled purchases

Selling operating model, software, and support as three independent decisions lets teams adopt incrementally and pay only for what they need — lowering the barrier to the first paid dollar. See outcome-based pricing trends.

Areas to improve : Gaps in Kill Bill’s pricing approach

1. No public per-tier price list

Aviate and support are quote-stage, so beyond the ~$40/mo AWS deploy and the single $25M-ARR calculator example, buyers cannot self-qualify exact costs. Publishing even indicative Aviate/support bands would shorten evaluation. See bill shock and cost unpredictability.

2. TCO of self-hosting is under-stated

The “free” headline is real for the engine, but the infrastructure and engineering cost to run mission-critical billing is significant and not surfaced on the pricing page — buyers must model it themselves.

3. ROI skews to higher ARR

The flat-fee advantage over a percentage-of-revenue competitor is strongest at higher ARR; smaller teams may find a managed SaaS competitor cheaper before the lines cross, which the calculator’s $25M default can obscure.

Key takeaways

1. The engine is free — full stop. Kill Bill’s open-source billing & payments platform (Apache-2.0) has no license fee, no usage meter, and no percentage of revenue; you pay only for your own infrastructure.
2. Money is made on optional, modular layers. Revenue comes from an AWS Marketplace deploy (~$40/mo software fee), cumulative Aviate software tiers, and flat-annual-fee support — bought independently.
3. Flat fees are the whole pitch. By never tying price to revenue, a customer’s cost stays flat as they scale — the page sells ~$50k–$75k/yr at $25M ARR versus ~$175k for a 0.7%-of-revenue competitor.
4. You trade infrastructure burden for control and predictability. The real cost is operational — owning the stack, the data, and the upgrades — in exchange for no lock-in and no revenue share.
5. Open-core billing can compete on pricing model, not just features. Kill Bill’s flat-fee posture is itself the differentiator against SaaS billing vendors that meter revenue.

UBP implications

1. Not all billing infra monetizes by usage — and that can be the wedge. Kill Bill deliberately rejects per-transaction and percentage-of-revenue metering, proving a flat-fee model can win buyers tired of paying more as they grow. See usage-based pricing strategy.
2. Open-core decouples value capture from the meter. Giving the engine away and charging for tooling/support shifts monetization off the usage curve entirely — relevant for anyone weighing usage-based versus subscription/support revenue.
3. Predictability is a value metric. “Fees stay flat as you scale” is a sellable promise precisely because percentage-of-revenue billing creates bill-shock anxiety — a UBP lesson in when not to meter.

Sources

• Kill Bill pricing page (accessed 2026-06-10) — three-decision model, Self-Hosted Free, AWS Marketplace ~$40/mo, Aviate tiers, flat-fee support, savings calculator ($12k Aviate + $38k–$63k Growth Support = $50k–$75k vs $175k at 0.7% at $25M ARR)
• Kill Bill official website (accessed 2026-06-10) — products (Subscription Billing, Payment Platform, Kaui), open-source positioning
• Kill Bill on GitHub (accessed 2026-06-10) — Apache-2.0 license, ~2010 origin, 5.6k+ stars
• Kill Bill documentation (accessed 2026-06-10)

Bottom line

Kill Bill is the leading open-source subscription billing & payments platform — and its pricing is its differentiator: the engine is genuinely free (Apache-2.0, self-host), with no usage meter and no percentage of revenue. Commercial revenue comes from three independent, modular decisions: operating model (Self-Hosted Free, AWS Marketplace ~$40/mo software fee, or a ChaChing-run Hosted Platform), cumulative Aviate software tiers, and flat-annual-fee support. Kill Bill’s own calculator shows a representative ~$50k–$75k/yr package at $25M ARR versus ~$175k for a 0.7%-of-revenue competitor — roughly $110k+ in savings that grows as you scale. The trade-off is operational: you own the infrastructure and upgrade burden in exchange for control, no lock-in, and fees that never rise with your revenue. Browse the pricing blueprint for more fully-researched company profiles.

Want to compare Kill Bill against other billing & monetization infrastructure companies? Browse the pricing blueprint.

Pricing timeline : Major events on a vertical axis

Each milestone below corresponds to a public pricing change, product launch, or material adjustment. Major events use a filled marker; minor adjustments use a faded one.

Three-decision pricing page (operating model · software · support)

Jun 2026

Current shape: choose an operating model (Self-Hosted Open Source Free, AWS Marketplace ~$40/mo software fee, or ChaChing-run Hosted Platform), then for customer-managed deployments pick an Aviate capability tier and a flat-fee support level. The page's calculator shows ~$50k–$75k/yr at $25M ARR vs ~$175k for a 0.7%-of-revenue competitor.

Aviate enterprise tooling + flat-fee support productized

Jan 2024

The commercial layer matures into modular add-ons on top of the free engine: 'Aviate' software tiers (Entourage, Growth, Flock, Finance) and flat-annual-fee support plans (Launch, Growth, Enterprise), plus an AWS Marketplace deploy. Pricing is positioned as flat and predictable, deliberately decoupled from customer revenue.

Open-source billing engine launches (Apache-2.0)

Jan 2010

Kill Bill is released as a free, Apache-2.0 open-source subscription billing & payments platform on GitHub. The engine has been free to self-host from day one — no per-usage meter, no percentage of revenue — establishing the open-core posture the commercial model still rests on.