Integrate tax features into your platform

Which tax features can be integrated into platforms?

Use cases for digital tax features via API are versatile and go far beyond a single form. With AnyTax, you can provide various features modularly:

Full tax filings: For private individuals, employees, families, freelancers, or sole proprietors.
Dynamic tax estimations: To show users during the year how financial decisions impact their tax outcome.
Tax calculations: To calculate expected tax refunds for your users, such as for investment income or crypto transactions.

Platforms looking to build these features in-house usually face the same major hurdles: developing and constantly maintaining accurate tax logic alongside changing tax laws, establishing a connection to the ELSTER tax administration interface, and embedding everything seamlessly into their existing UX. On top of that, questions around operational and regulatory responsibility quickly arise.

The following sections detail how AnyTax resolves exactly this complexity.

Typical challenges when integrating tax features

ELSTER integration via AnyTax

ELSTER Interface: Active

Direct Submission Fully Automated

Transmissions to the tax authorities are routed through the ELSTER interface. AnyTax built and maintains this connection independently within its own backend — meaning no reliance on third-party providers or software resellers.

For your application, this means tax features execute seamlessly directly within your product. Your customers experience an end-to-end journey in their familiar design, maintain trust in your brand, and never need to manually export data.

Advantages over in-house development:

No development or ongoing maintenance of a custom ELSTER interface
No effort required for complex tax logic or automatic backend updates for new legislation
Significant reduction in development effort, costs, and time-to-market

Which integration option fits your platform?

We offer API, SDK, White-Label, and custom integration solutions. The underlying backend tax logic is identical across all four options — the difference lies in UI design flexibility and required development effort.

	API	SDK	White-Label	Custom
User Interface (UI)	Built entirely by you	Pre-built, customizable UI components	Turnkey	Custom
Technical Format	REST API	Web & Mobile SDK	Web App or iFrame	Custom
Development Effort	Higher (Frontend in-house dev)	Low	Minimal	Custom
Time-to-Market	Implementable in weeks	Very fast	Fastest	Custom
Branding & Design	100% native UI design	Flexibly configurable components	Your branding on our standard UI	Custom
Ideal if you...	want full control over UI design and UX.	want to launch quickly and customize visual styling.	want to embed turnkey tax features with your branding.	have specific enterprise requirements.

Which tasks does AnyTax handle — what remains with your platform?

Whether API, SDK, or White-Label: backend technical and regulatory responsibility remains with us. You retain the customer relationship and UI/UX; we provide the tax infrastructure.

Scope & Responsibility	AnyTax Tax API	Your Platform
Tax logic & tax calculation	Yes (Included)	–
ELSTER submission to tax authority	Yes (Included)	–
Compliance & annual legislative updates	Yes (Included)	–
GDPR compliance & hosting in Germany	Yes (Included)	For own systems
Customer relationship	–	100% with your platform

Submission process note: Following successful transmission, processing rests exclusively with the tax administration. The final refund amount and payout timeline are determined by the tax office.

A wealthtech platform leverages the tax API to natively integrate tax filings and dynamic forecasts directly into its user interface. An expat community utilizes our white-label solution to offer turnkey tax features with zero engineering overhead. A portfolio tracker relies on our infrastructure to automate tax return pre-filling from complex transaction data.

All of these platforms share the same core strategy: delivering immediate value to their users, boosting customer retention, and expanding their product ecosystems.

Why platforms embed tax features instead of building them in-house

Native User Experience

Native User Flow Zero Friction Tax API

Frequently Asked Questions about Integration

Does AnyTax completely replace custom ELSTER interface development?

Yes. Via the AnyTax Tax API, you don't need your own ELSTER infrastructure. Your developers don't need to integrate ERiC libraries, manage certificates, or handle annual interface updates.

Can we start with White-Label and switch to the Tax API later?

Yes. Because the underlying tax infrastructure and backend processes are identical across all integration methods, switching later only changes the user interface (UI). Core processes remain untouched.

Does our engineering team face maintenance overhead for annual tax law changes?

No. Legal updates, new ELSTER specifications, and updated calculation logic are maintained centrally by AnyTax in the backend. Your dev team incurs no ongoing effort to update form logic.

How complex is the technical integration, and how is it tested?

The integration is designed for fast time-to-market. Guided by developer documentation and a dedicated sandbox test environment, your engineering team can test data flows and submissions prior to go-live.

How is GDPR compliance and data security ensured?

Data processing is 100% GDPR-compliant on servers in Germany (EU) using encrypted data transmission following modern security standards. AnyTax operates under a Data Processing Agreement (DPA); the customer relationship remains entirely with your platform.

For more details on privacy, IT security, and certifications, visit our frequently asked questions (FAQ).

How do I integrate tax features into my platform?