Accounting Software Compatible with Peppol in the Netherlands: A Complete Guide

How to Connect Your Existing Accounting Software to Peppol

The promise of e-invoicing is automation: invoices flow seamlessly between businesses without manual data entry, paper handling, or email management. But this promise only becomes reality when your accounting software is properly connected to the Peppol network.

In the Netherlands, Peppol is already mandatory for public sector invoicing and will become mandatory for B2B by July 2030 under the EU's ViDA directive. The good news? You do not need to switch accounting software to comply. Whatever solution you currently use -- whether it is a cloud-based platform, an on-premise ERP, or a simple bookkeeping tool -- Peppol Box adapts to your setup and bridges the gap to the Peppol network.

This guide explains the different ways to connect your existing tools to Peppol, so you can start sending and receiving compliant e-invoices without disrupting your current workflow.

Does Your Software Already Support Peppol?

Many popular accounting solutions on the market already offer some level of Peppol support. Depending on the platform, this can range from basic UBL export to full native Peppol sending and receiving. Here is what to check:

• Native Peppol connectivity: Some larger cloud platforms offer built-in sending and receiving of Peppol invoices. If your software has this, you may already be partially covered.
• UBL export only: Many tools can generate invoices in UBL format, but lack the ability to transmit them over the Peppol network. In this case, you need an Access Point like Peppol Box to handle the delivery.
• No e-invoicing support: Some older, niche, or simpler packages do not support structured invoicing at all. This does not mean you are locked out -- Peppol Box can work alongside these tools.

Even if your software has native Peppol support, Peppol Box can add value as a complementary layer -- providing a dedicated dashboard, mobile access, enhanced validation, and a centralised view of all your Peppol traffic.

Connection Method 1: Peppol Box Web Portal and Apps

The most straightforward way to connect to Peppol is through the Peppol Box web portal and mobile apps (iOS and Android). This method requires no technical integration at all:

• Create and send invoices: Build compliant SI-UBL or Peppol BIS invoices directly in the Peppol Box dashboard or mobile app, and send them over the Peppol network with a click.
• Receive invoices: All incoming Peppol invoices arrive in your secure Peppol Box inbox with notifications, processing status, and search functionality.
• SEPA QR Code: Each received supplier invoice automatically includes a SEPA QR Code for easy payment.
• Accounting export: Download received and sent invoices in PDF, UBL XML, or other formats compatible with your accounting software (WinBooks, Sage, Exact Online, and more).

Peppol Box is ideal for businesses that want to get started quickly. Register with your KvK number, and your Peppol ID is created automatically. Pricing starts from €5/month, with a 3-month trial for €5.

Connection Method 2: CSV and XML Import/Export

If your accounting software supports exporting data in CSV or XML format -- which most do -- you can use this as a bridge to Peppol Box. This method is straightforward and does not require any technical integration:

1. Export your invoices from your accounting software in CSV or XML format
2. Import them into Peppol Box using the bulk upload feature on the web portal or mobile app
3. Peppol Box converts and sends the invoices in the correct SI-UBL or Peppol BIS format over the Peppol network

For incoming invoices, the process works in reverse: Peppol Box receives Peppol invoices and lets you export them as CSV or XML files that you can import into your bookkeeping tool.

This method is particularly useful for businesses with moderate invoice volumes that want a simple, low-cost connection without any software development.

Connection Method 3: Peppol Box API (Custom Integration)

For businesses that want full automation and have access to development resources, the Peppol Box API provides the most flexible connection method. The API allows you to:

• Send invoices programmatically: Submit invoice data from any system and have Peppol Box generate, validate, and send compliant Peppol invoices
• Retrieve incoming invoices: Pull received Peppol invoices directly into your own system via API calls
• Query status: Check delivery status, validation results, and error details for any invoice
• Manage participants: Look up Peppol participants, verify KvK numbers, and manage your contact list

The API is available for automation and is designed for developers who want to build a tight integration between their existing systems and the Peppol network. It is used by ERP vendors and businesses with custom-built financial software.

Bonus: Flexina Sync for Your Accountant

Flexina Sync is a free tool designed exclusively for accountants and tax advisors. It lets your accountant automatically retrieve your invoices from Peppol Box -- with no effort on your part.

Flexina Sync offers four retrieval methods for accountants:

• Email: Your accountant receives an email with a download link (PDF or XML)
• Web portal: A dedicated portal to view, filter, and batch download client invoices
• Desktop application: A Windows/Mac app with automatic folder sync, format choice, and configurable frequency
• Platform integration: Direct integration with existing systems such as Billtobox, Billit, and Horus

Flexina Sync is compatible with a wide range of accounting software, including Expert/M, WinAuditor, Horus, Adsolut, Octopus, WinBooks, Yuki, Venice, Sage BOB, Exact Online, and ClearFacts -- essentially any software that accepts UBL XML or PDF files. It is completely free for accountants and requires no action from you as a business user.

Which Method Is Right for You?

The best connection method depends on your business size, invoice volume, and technical resources:

• ZZP'ers and freelancers: Start with the Peppol Box web portal or mobile app. Simple, fast, and no technical setup required.
• Small businesses (up to 50 employees): The web portal combined with CSV/XML exchange offers the right balance of convenience and simplicity.
• Mid-sized companies: CSV/XML exchange or the Peppol Box API provides flexible integration with your existing accounting software.
• Large enterprises and developers: The Peppol Box API gives you full control and the flexibility to build custom workflows that fit your existing infrastructure.
• All businesses: Tell your accountant about Flexina Sync -- it is a free tool that lets them automatically retrieve your invoices from Peppol Box, saving everyone time.

Regulatory Context: Why This Matters Now

Connecting your accounting software to Peppol is not just a convenience -- it is becoming a legal necessity. Here is the regulatory timeline:

• Already mandatory (B2G): All suppliers to the public sector must send invoices via Peppol in SI-UBL format
• July 2030 (B2B): Under the EU's ViDA directive, all B2B invoices must be issued in a structured electronic format. PDF invoices will no longer satisfy legal requirements.
• Digital Reporting Requirements: Invoice data will need to be reported to the Belastingdienst in near-real-time, making structured data essential

Businesses that connect to Peppol now gain immediate benefits in efficiency and cost savings, while also being fully prepared for the 2030 mandate.