API Terms of Service

These terms govern your use of the Solid Accounting Integration Engine API ("the API"). The API is included with all license tiers and lets you build integrations between Solid Accounting and other software.

By using the API, you agree to these terms in addition to the EULA and Terms of Service. If there's a conflict, these API terms control for API-specific matters.

What you can do

• Build integrations that read and write data to your own Solid Accounting installation
• Connect Solid Accounting to other software you use (ERP, CRM, payroll, POS, e-commerce, etc.)
• Automate workflows involving your own accounting data
• Build internal tools for your organization

What you can't do

• Build a product or service that replicates Solid Accounting's core functionality using the API
• Resell, sublicense, or commercialize access to the API itself (you can sell your integration, but not raw API access)
• Use the API to extract data for purposes unrelated to your accounting workflow (data mining, training AI models, competitive analysis)
• Exceed the rate limits described below
• Circumvent authentication, rate limiting, or other technical controls
• Use the API to transmit malware, exploit vulnerabilities, or attack Solid Accounting or other users' systems
• Access or attempt to access data belonging to other Solid Accounting users

Rate limits

Tier	Requests per minute	Requests per day	Concurrent connections
Professional	60	10,000	5
Enterprise	120	50,000	15
Accountant	200	100,000	25

Rate limits apply per installation. If you exceed a limit, the API returns HTTP 429 (Too Many Requests) with a Retry-After header. Sustained abuse of rate limits may result in temporary API suspension.

We may adjust rate limits with 30 days' notice. We'll always provide enough headroom for legitimate integrations.

Authentication

All API requests must be authenticated. The API uses token-based authentication. You are responsible for keeping your API tokens secure:

• Don't hard-code tokens in source code
• Don't share tokens across installations
• Don't expose tokens in client-side code, public repositories, or logs
• Rotate tokens periodically (we recommend at least every 90 days)

If a token is compromised, revoke it immediately in Settings > API and generate a new one.

Data and privacy

• The API accesses only the data on your local Solid Accounting installation — it does not send data to our servers (unless you're using an online feature like the invoicing portal)
• You are the data controller for any data accessed through the API
• If your integration sends Solid Accounting data to a third-party service, you are responsible for ensuring that transfer complies with applicable privacy laws (GDPR, CCPA, etc.)
• We are not responsible for what third-party services do with your data once it leaves Solid Accounting

IP ownership

• Solid Accounting owns the API — the endpoints, documentation, protocols, and all underlying code
• You own your integrations — the code you write that calls the API is yours
• You may not claim ownership of or patent any part of the API itself
• We grant you a non-exclusive, revocable license to use the API for the purposes described above, subject to these terms

API changes and versioning

• We version the API. Breaking changes only happen in major version bumps
• We'll maintain the current major API version for at least 12 months after releasing a new major version
• Deprecation notices are published in the API documentation and sent via email at least 90 days before removal
• Bug fixes and non-breaking additions may happen at any time without notice

Availability and SLA

The API runs locally on your machine — its availability depends on your Solid Accounting installation being running. We do not provide an uptime SLA for the local API.

For API endpoints that interact with online services (invoicing portal, bank feeds), availability depends on those services. See the Security Practices for infrastructure details.

Liability

THE API IS PROVIDED "AS IS" WITHOUT WARRANTY OF ANY KIND. We are not liable for:

• Errors, data loss, or corruption caused by your integrations
• Downtime or unavailability of third-party services your integration connects to
• Security breaches resulting from improperly secured API tokens
• Business losses arising from API changes, deprecation, or rate limiting
• Data transmitted by your integration to third-party services

Our total liability for API-related claims is limited to the amount you paid for your Solid Accounting license in the 12 months preceding the claim, as set forth in the EULA.

Suspension and termination

We may suspend your API access if:

• You violate these terms or the EULA
• Your usage pattern suggests abuse (sustained rate limit violations, automated scraping, vulnerability probing)
• Required by law

We'll provide notice before suspension when possible. For security incidents, we may suspend immediately and notify after.

Your API access ends when your Solid Accounting license ends. See the EULA for license termination details.

Third-party integrations

We may maintain a directory of third-party integrations built by other developers. Listing in this directory does not constitute endorsement. We are not responsible for third-party integration quality, security, or data handling. Use third-party integrations at your own risk and review their privacy policies before granting them API access.

Changes to these terms

We may update these terms with at least 30 days' notice by email. Continued API use after the effective date constitutes acceptance.

Contact

Questions about these terms or the API? legal@solidaccounting.com or support@solidaccounting.com