The Fincome API lets you import and manage your Fincome account's data. It is accessible from the interface (Settings > API Developer menu), where you can create a secret key for authentication.

By sending your data in JSON format via our dedicated endpoints, you can use all of Fincome's analyses (MRR, ARR, churn, revenue recognition...) as if your data came from a native integration.

This method is particularly useful if:

• you manage your invoices in an unconnected internal ERP,
• you want to automate the import without handling files,
• or if you are migrating from another billing system.

Key recommendations

Expected format

The data must be sent in standardized JSON format, respecting the schema required by Fincome. Each invoice must contain:

• a unique identifier,
• the associated customer's ID,
• an issue date,
• a payment status (open, paid, unpaid),
• and a net amount. Make sure to respect standard date formats (ISO 8601) and valid status values.

Endpoints to use

• POST /invoices → to create new invoices
• POST /subscriptions → to create or update the associated subscriptions

Each invoice must reference an existing subscription and customer in order to be correctly attached in Fincome.

Concrete use case For example, you can export the monthly invoices from your internal ERP in JSON format, then integrate them into Fincome via the API. Your revenue will thus be taken into account in Fincome even if your billing system is not directly connected.

Point of attention: Make sure to respect the mapping of the required fields. Each record must include unique identifiers (to avoid duplicates), correctly formatted dates, consistent billed amounts, and statuses that meet Fincome's expectations. A correct mapping guarantees that your data will be integrated without errors and analyzed correctly by the platform.

API technical documentation

Fincome API | Fincome technical documentationdocs.fincome.co

Business case

At Soeman, the technical team chose to integrate Fincome via the API in order to simplify the management of financial data and give management a reliable, real-time view of its key KPIs: ARR, MRR, churn, retention.

We chose the API because it is simpler, automated, and real-time. It saves us manual imports via CSV files and allows our solution to transmit information automatically.
Samuel Burey, Technical Manager at Soeman

Thanks to this integration, Soeman automated the sending of its data, gained reliability, and eliminated all manual handling. A concrete example of the power of the Fincome API for recurring-revenue companies.

🔗 Read the full testimonial: Case study – Fincome API integration at Soeman

Updated on: 03/07/2026