Exact Online API Integration
Exact Online is a leading cloud accounting platform in the Netherlands and Belgium, with significant adoption across other European markets. Integrate Exact Online alongside dozens of other accounting and ERP systems through Maesn Unified API.
Exact Online Partner
Have an Exact Online
Integration in Days
Exact Online sandbox included
Exact Online's own sandbox can take time to access. maesn's is ready immediately, so you can start building today.
NL, BE, DE and UK — fully supported
Every country-specific implementation of Exact Online covered out of the box.
One integration, all markets.
Exact Partner support included
As an official Exact Partner, Maesn guides you through every step. From first call to App Store listing.
How Tipalti accelerated market entry in Benelux and DACH with Maesn
Tipalti, one of the world’s leading AP automation platforms, uses Maesn for multiple ERP integrations, including Exact Online, to accelerate customer expansion across key European markets.
“With Maesn, we were able to accelerate our European expansion significantly by making integration into local ERP systems seamless for customers across Benelux and DACH.”
Saad Abouyahya
Sr. Manager - Global Technology Platforms & Strategic Partnerships @ Tipalti
One API for Exact Online
and every system that comes after.
Unified. Certified. Production-ready.
Get listed in the Exact App Store with your own app.
Get your app officially reviewed and published in the Exact App Store under your own name. Benefit from Exact's marketplace with co-marketing activities and strengthen your positioning across Netherlands, Belgium, Germany and UK.
Your app, your name — maximum growth effect
Get official Exact Partner
Full integration support & co-marketing by maesn
Extended Exact Online webhooks with Maesn.
Exact Online's native webhooks cover only a limited set of objects. Maesn extends this with synthetic webhooks — so every object, every endpoint, is reachable in real time without polling.
Native & synthetic webhooks combined
Every Exact Online object covered
Unified, normalized payloads
Complete Exact Online data — without multi-call complexity.
Some data points in Exact Online aren't directly exposed via API. Payment status on invoices being one example. Maesn handles the underlying complexity in the background, delivering a single, complete response — just like every other system.
Webhooks for every endpoint, every system
Unified, normalized payloads
Synthetic Webhooks
Everything you can build with Exact Online.
From invoice creation to full AP/AR automation — maesn gives you the endpoints to build any accounting workflow directly into your product, all through one unified API.
Create invoices & sync customer and supplier data
Automate accounts payable & receivable workflows
Financial analysis with real-time Exact Online data
Everything you need to start building today.
The Maesn docs cover every Exact Online endpoint, authentication flow, and implementation detail — plus a full overview of the current coverage, which is continuously being expanded.
Custom fields & objects fully accessible
Authenticated Passthrough for any user endpoint
Raw Data for full, unfiltered system responses
Get Exact partner and
listed in Exact App Store with Maesn
Maesn's Exact Online sandbox lets you start developing immediately. Get your product listed in Exact's App store, reaching a large, concentrated base of Benelux and DACH customers directly.
Whitepaper: European ERP & accounting market
Get insights and learn about the most imoportant systems in our country-by-country view of the European ERP and Accounting software landscape.
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3 Reasons why it is better to integrate Exact Online API with Maesn
Save months of effort
No need to build complexity workflows in Exact — Maesn removes months of learning and implementation effort.
Save thousands of euros
Avoid costly clarification rounds, external support, and repeated coordination before going live.
Work with a proven partner
Maesn powers Exact Online integrations trusted by hundreds of companies — we know what works.
We are European.
Enterprise-grade security & compliance are our foundation.
Built and hosted in Germany to meet the highest security and compliance standards, Maesn processes API calls in real time without storing customer data and is fully ISO 27001 & GDPR compliant.
Read more in our related blog articles.
Everything you need to know about Exact Online
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Frequently asked
questions
You have more questions? We are looking forward hearing from you - book a meeting now!
Is Maesn an official Exact Online partner?
Yes, maesn is an official Exact Partner. Your integration can be officially reviewed and listed in the Exact App Store under your own product name.
Which Exact Online countries does Maesn support?
Maesn supports all major Exact Online regions — Netherlands, Belgium, Germany, and UK — including all country-specific implementations out of the box.
How long does it take to integrate Exact Online with Maesn?
Most teams have a working Exact Online integration within days to weeks. Maesn provides sandbox access, thorough documentation, and direct partner support to get you to production fast.
Does Maesn support Exact Online webhooks?
Yes, maesn combines native and synthetic webhooks to cover every Exact Online object in real time, including objects that Exact doesn't natively expose via webhook.
What if Exact Online doesn't expose certain data points natively?
Maesn handles multi-call complexity in the background. Data points like payment status on invoices — which require multiple underlying API calls in Exact Online — are delivered as a single, clean response.
Can I access custom or non-standard Exact Online endpoints?
Yes, Maesn's Authenticated Passthrough lets you call any endpoint within the user's authenticated Exact Online environment directly, including custom objects and system-specific fields.
How does Maesn handle Exact Online authentication?
Maesn abstracts the full OAuth flow for Exact Online and supports multi-company setups, automated token management, and the Interactive Authentication Flow for environment and company selection.