The Challenge
As of January 1, 2026, e-invoicing is mandatory in Croatia for all VAT payers for domestic transactions. This obligation arises from increasing legislative requirements for electronic invoicing and fiscalization. The goal was to prepare a solution that enables secure invoice exchange while simplifying invoice processing. At the same time, emphasis was placed on maintaining compatibility with existing systems, even when handling high invoice volumes.
As the company was already using the Flowis system to automate the processing of supplier invoices, it decided to extend its use to electronic invoicing as well.
Key Challenges:
- Compliance with legislative requirements.
- Multiple source systems (SAP and BWG system).
- Ensuring consistent data formats and mandatory elements such as numbering structure, required markings, and specific data fields.
- Limited implementation time, requiring a pragmatic and fast deployment approach.
Solution: Flowis Implementation
Integration and Consolidation of Invoices From Multiple Systems
Flowis acts as a centralized platform that consolidates and processes data from multiple accounting systems used by BIPA. It handles the exchange of invoicing data via API and SFTP, while system-specific differences are managed behind the scenes. This allows BIPA to handle all invoices in a uniform manner, regardless of their source.
Ensuring Mandatory Legislative Requirements
Flowis ensures that invoices have the correct format and contain all mandatory information. In cases where BIPA’s accounting systems did not allow the required identification details on issued invoices to be modified or supplemented, Flowis provided this capability.
Sending and Receiving E-invoices via Flowis
Flowis acts as the central system for processing both issued and received e-invoices. Issued invoices are automatically transferred to Flowis from source systems and subsequently sent via an IP provider for fiscalization and delivery to the recipient. At the same time, Flowis also processes and fiscalizes received supplier invoices, which, in the case of domestic suppliers, are delivered in electronic (XML) format.
The solution is designed to handle high volumes—approximately 16,000 issued and 52,000 received domestic invoices are processed via Flowis.
Automated Processing of Domestic Invoices without OCR
Domestic supplier invoices in XML format are processed fully automatically in the Flowis system. Thanks to the structured format, all data is available directly, without the need for data extraction.
Flowis also has automatic checks in place that notify the user if a PDF invoice from a domestic supplier is uploaded to the system. The system message informs the user that, as of January 1, 2026, the invoice must be delivered in XML format via a digital postman.
The Results and Benefits
The outcome for BIPA includes the following key benefits:
Full compliance with
legislative requirements
Full compliance with legislative requirements.
One central system
for e-invoices
Improved transparency and process control.
Reduced
manual effort
XML format eliminates manual uploads and validations.
Automated
data transformation
Conversion into required formats without manual intervention.
Scalability for large
document volumes
Approximately 16,000 issued and 52,000 received domestic invoices.
Extended cooperation
and further solution development
A follow-up project phase focuses on e-reporting.
