# FastSpring vs Kill Bill

| Attribute | FastSpring | Kill Bill |
|---|---|---|
| **Vioscale score** | 51.9 (18% (low)) | 44.6 (77% (high)) |
| activity.commits_last_30d | - | 35 |
| adoption.dependent_repos | - | 15 |
| adoption.github_stars | - | 5,703 |
| deployment.options | `{"cloud":true}` | `{"cloud":true,"hybrid":true,"on_prem":true,"self_hosted":true}` |
| description.long | FastSpring is a merchant of record platform providing global payment processing, subscription management, tax compliance, checkout optimization, and comprehensive billing tools for digital products, SaaS, and software vendors. | Kill Bill is an open-source billing and payments platform that handles complex subscription, usage-based, and prepaid billing models with multi-currency invoicing, tax compliance, and payment gateway abstraction. Deploy self-hosted or use fully managed hosting with optional enterprise accelerator capabilities. |
| features.capabilities | `{"dunning":"none","analytics":true,"api_first":true,"invoicing":true,"tax_handling":"native","self_hostable":false,"pricing_models":"Subscription, one-time purchases, recurring payments","usage_metering":"none","catalog_management":true,"merchant_of_record":true,"revenue_recognition":"none","subscription_billing":true}` | `{"dunning":"basic_retry","gl_sync":false,"analytics":true,"api_first":true,"invoicing":true,"tax_handling":"native","self_hostable":true,"pricing_models":"Subscriptions, usage-based, prepaid, postpaid, hybrid, and complex multi-currenc","usage_metering":"real_time","catalog_management":true,"merchant_of_record":false,"revenue_recognition":"native_asc606","subscription_billing":true}` |
| integrations.count | 20 | 9 |
| integrations.list | `[{"name":"HubSpot"},{"name":"Mailchimp"},{"name":"Zapier"},{"name":"WordPress"}]` | `[{"name":"Stripe"},{"name":"Adyen"},{"name":"Braintree"},{"name":"PayPal"},{"name":"GoCardless"},{"name":"Avalara"},{"name":"Vertex"},{"name":"LDAP"},{"name":"Active Directory"}]` |
| language.primary | - | Java |
| license.spdx | - | Apache-2.0 |
| market.availability | - | `{"primaryMarkets":["US"],"availabilityScope":"global","availableCountries":[],"notAvailableCountries":[]}` |
| platform.support | `{"ios":true,"web":true,"android":true}` | `{"cli":true,"web":true}` |
| pricing | - | `{"type":"hybrid","plans":[{"free":true,"name":"Open Source (Self-Hosted)","features":["Full source code access","Docker deployment","Community support","Full infrastructure control"],"components":[{"kind":"one_time","amount":0,"currency":"USD"}],"description":"100% open-source, community supported, deploy in your infrastructure","contactSales":false},{"free":false,"name":"AWS Marketplace","features":["AWS account deployment","Faster evaluation path"],"components":[{"kind":"fixed","amount":40,"period":"month","currency":"USD"}],"description":"Managed Kill Bill in your AWS account","contactSales":false},{"free":false,"name":"Aviate - Foundation","features":["Core admin and billing configuration","Pre-configured test environment","Operational views"],"description":"Admin workspace for Kill Bill operations","contactSales":true},{"free":false,"name":"Aviate - Growth","features":["Everything in Foundation","Dynamic catalog and pricing rules","Usage metering","Programmatic control"],"description":"Catalog, pricing, and metering control plane","contactSales":true},{"free":false,"name":"Aviate - Flock","features":["Everything in Growth","Quote, order, contract workflows","Operational BI dashboards","Commercial diagnostics"],"description":"Quote-to-cash commercial operations","contactSales":true},{"free":false,"name":"Aviate - Finance","features":["Everything in Flock","Revenue recognition","Accounting periods","Multi-entity governance"],"description":"Finance-grade controls and governance","contactSales":true}],"addOns":[{"name":"Launch Support"},{"name":"Growth Support"},{"name":"Enterprise Support"}],"summary":"Free open-source tier. Aviate software tiers (Foundation, Growth, Flock, Finance) priced separately as annual flat fees. Support plans as additional annual flat fees (Launch, Growth, Enterprise).","currency":"USD","freeTier":true,"sourceUrl":"https://killbill.io/pricing.html","retrievedAt":"2026-08-14T13:38:55.933Z","startingPrice":{"amount":40,"period":"month","currency":"USD"},"billingPeriods":["month","year"]}` |
| pricing.free_tier | - | yes |
| pricing.model | commercial | commercial |
| pricing.price_level | - | mid |
| pricing.transparent | - | yes |
| release.cadence_days | - | 36 |
| release.history | - | `[{"url":"https://github.com/killbill/killbill/releases/tag/killbill-0.24.21","date":"2026-08-12T06:47:08Z","type":"stable","version":"killbill-0.24.21"},{"url":"https://github.com/killbill/killbill/releases/tag/killbill-0.24.20","date":"2026-08-07T06:01:08Z","type":"stable","version":"killbill-0.24.20"},{"url":"https://github.com/killbill/killbill/releases/tag/killbill-0.24.19","date":"2026-07-09T05:52:01Z","type":"stable","version":"killbill-0.24.19"},{"url":"https://github.com/killbill/killbill/releases/tag/killbill-0.24.18","date":"2026-05-14T06:25:50Z","type":"stable","version":"killbill-0.24.18"},{"url":"https://github.com/killbill/killbill/releases/tag/killbill-0.24.17","date":"2026-04-23T08:34:31Z","type":"stable","version":"killbill-0.24.17"},{"url":"https://github.com/killbill/killbill/releases/tag/killbill-0.24.16","date":"2025-11-25T10:52:32Z","type":"stable","version":"killbill-0.24.16"},{"url":"https://github.com/killbill/killbill/releases/tag/killbill-0.24.15","date":"2025-07-21T06:08:44Z","type":"stable","version":"killbill-0.24.15"},{"url":"https://github.com/killbill/killbill/releases/tag/killbill-0.24.13","date":"2025-02-07T13:03:42Z","type":"stable","version":"killbill-0.24.13"},{"url":"https://github.com/killbill/killbill/releases/tag/killbill-0.24.12","date":"2024-10-29T12:47:14Z","type":"stable","version":"killbill-0.24.12"},{"url":"https://github.com/killbill/killbill/releases/tag/killbill-0.24.11","date":"2024-09-09T13:01:01Z","type":"stable","version":"killbill-0.24.11"},{"url":"https://github.com/killbill/killbill/releases/tag/killbill-0.24.10","date":"2024-03-18T14:54:37Z","type":"stable","version":"killbill-0.24.10"},{"url":"https://github.com/killbill/killbill/releases/tag/killbill-0.24.9","date":"2024-02-29T09:03:30Z","type":"stable","version":"killbill-0.24.9"},{"url":"https://github.com/killbill/killbill/releases/tag/killbill-0.24.7","date":"2024-02-06T08:26:00Z","type":"stable","version":"killbill-0.24.7"},{"url":"https://github.com/killbill/killbill/releases/tag/killbill-0.24.6","date":"2024-02-01T03:26:56Z","type":"stable","version":"killbill-0.24.6"},{"url":"https://github.com/killbill/killbill/releases/tag/killbill-0.24.5","date":"2023-08-25T11:36:49Z","type":"stable","version":"killbill-0.24.5"},{"url":"https://github.com/killbill/killbill/releases/tag/killbill-0.24.4","date":"2023-07-20T06:09:10Z","type":"stable","version":"killbill-0.24.4"},{"url":"https://github.com/killbill/killbill/releases/tag/killbill-0.24.3","date":"2023-06-27T07:33:33Z","type":"stable","version":"killbill-0.24.3"},{"url":"https://github.com/killbill/killbill/releases/tag/killbill-0.24.2","date":"2023-05-02T10:51:38Z","type":"stable","version":"killbill-0.24.2"},{"url":"https://github.com/killbill/killbill/releases/tag/killbill-0.22.33","date":"2023-04-19T22:10:47Z","type":"stable","version":"killbill-0.22.33"},{"url":"https://github.com/killbill/killbill/releases/tag/killbill-0.24.1","date":"2023-03-14T00:49:10Z","type":"stable","version":"killbill-0.24.1"}]` |
| reliability.sla_pct | - | 48 |
| reliability.status_page | yes | - |
| security.gdpr | yes | yes |
| security.pci | - | yes |
| security.scorecard | - | 4.5 |
| security.vulnerabilities | - | `{"count":0,"source":"https://advisories.ecosyste.ms/api/v1/advisories?ecosystem=maven&package_name=org.kill-bill.billing%3Akillbill-util&per_page=100","last_12m":0,"max_severity":null}` |

## Capabilities (Billing & Invoicing Software)

| Capability | FastSpring | Kill Bill |
|---|:--:|:--:|
| **Core** |  |  |
| Subscription billing | ✓ | ✓ |
| Usage metering | None | Real-time |
| Pricing models | Subscription, one-time purchases, recurring payments | Subscriptions, usage-based, prepaid, postpaid, hybrid, and complex multi-currenc |
| Invoicing & AR | ✓ | ✓ |
| Catalog management | ✓ | ✓ |
| **Commerce** |  |  |
| Merchant of record | ✓ | ✗ |
| **Finance** |  |  |
| Revenue recognition | None | Native ASC 606 |
| Tax handling | Native | Native |
| **Collections** |  |  |
| Dunning | None | Basic retry |
| **Integrations** |  |  |
| GL / ERP sync | - | ✗ |
| **Ecosystem** |  |  |
| API-first / developer-first | ✓ | ✓ |
| **Deployment** |  |  |
| Self-hostable | ✗ | ✓ |
| **Insight** |  |  |
| Revenue analytics | ✓ | ✓ |

*Source: Vioscale. Generated 2026-09-01T20:41:00.339Z. "-" = undocumented, not absent.*