ERP and accounting integrations, through one API.
Maesn connects your product to 30+ ERP and accounting systems across Europe and beyond, through one REST API and one data model. Filter by country to see exactly what your customers run.
- systems live today
- 30+systems live today
- markets covered
- 20markets covered
- end-customers daily
- 10.000+end-customers daily
- REST API and data model
- 1REST API and data model
Connect once, reach every system
A list of logos only tells you what is possible. What matters is what you have to build, and what you never have to build again.
One integration instead of many
Connect once to Maesn and reach every supported system through the same REST API. Adding the next system is a configuration step, not another integration project.
One normalised data model
Invoices, contacts, ledgers and payments come back in one shared schema, with ISO country codes, currencies and dates, whichever system they came from.
Depth per system, not just endpoints
Maesn covers the depth of each system: more use cases, more data points and more objects than a shallow in-house integration reaches.
Certified and compliant by default
Built and hosted in Germany, ISO 27001 certified and GDPR compliant, with API calls processed in real time and no customer data stored.
Every one of them speaks the same API on your side, so the breakdown below is a list of what your customers already run, not work on your roadmap.
Every ERP and accounting system models the same business objects differently. An invoice in DATEV is not shaped like an invoice in Fortnox, dates and currencies follow different conventions and some systems will not return a complete object from a single endpoint at all. Maesn resolves that in one place: the common data model normalises field names, types, formats and object relationships, so your code reads the same invoice shape whichever system it came from.
The parts of an integration that usually cost the most time are unified too. Authentication is abstracted across API keys, OAuth, database credentials and two-factor flows, including multi-company interactive auth where one customer manages many entities. Change notifications arrive through one event model, even for systems that offer no webhooks of their own. You implement each of these once, not once per system.
Featured integration pages
DATEV, Sage, SAP Cloud ERP, Dynamics 365 Business Central, Xero and QuickBooks Online, each with its own page covering the objects, use cases and authentication flow for that system. SAP Cloud ERP is still in progress.
Browse every supported system
Every system: 30+ live today and more in progress, each marked as such. Search by name, narrow by SMB or Enterprise, and filter by the countries your customers operate in.
Showing 34 systems
Interface PartnerDATEV Unternehmen OnlineDATEV
DATEV's document exchange portal connecting businesses directly with their tax advisor's environment.
Interface PartnerDATEV RechnungswesenDATEV
Standard accounting platform for German tax advisors and larger self-booking companies across Germany.
sevdesk
German cloud accounting for SMBs and freelancers with GoBD-compliant invoicing and bookkeeping.
Lexware Office
Leading cloud accounting for German SMBs and freelancers, formerly known as lexoffice.
BuchhaltungsButler
German accounting automation focused on receipt capture and automated booking for SMBs and tax firms.
Xentral
German cloud ERP for e-commerce businesses covering order management, inventory and accounting.
Weclapp
German cloud ERP for SMBs covering CRM, accounting, inventory and e-commerce in one platform.
bexio
Cloud accounting for Swiss SMBs and freelancers covering invoicing, expenses and bank reconciliation.
Abacus
Swiss ERP for larger companies covering financials, payroll and project management with Swiss compliance.
Exact Online
Market leader for cloud accounting in the Netherlands and Belgium, also used in Germany, France, Spain, the UK and the US.
TwinfieldWolters Kluwer
Wolters Kluwer's cloud accounting used by firms managing multiple clients in Benelux, the UK, Germany and France.
Moneybird
Dutch cloud accounting for freelancers and small businesses with strong bookkeeper adoption.
SnelStart
Dutch accounting and invoicing platform widely used by SMBs and bookkeeping firms in the Netherlands.
Pennylane
French cloud accounting built around the accountant-client relationship, available in France and Germany.
Sage ActiveSage
Sage's cloud ERP for growing businesses in France, Spain and Germany with a GraphQL API.
Sage AccountingSage
Cloud accounting for SMBs across the UK, USA, France, Germany, Canada, Ireland and Spain.
HoldedVisma
All-in-one ERP for Spanish SMBs covering invoicing, accounting, inventory, CRM and HR.
FreeAgent
UK accounting for freelancers and contractors built around MTD VAT, Self Assessment and time tracking.
Xero
Cloud accounting for small businesses widely used in the UK, Australia, New Zealand and North America.
QuickBooks OnlineIntuit
Intuit's cloud accounting platform dominant in North America with a strong UK presence.
FreshBooks
Cloud accounting for freelancers and small service businesses across North America, the UK and Australia.
Fortnox
Sweden's most widely used SMB accounting platform covering invoicing, payroll and financial reporting.
Visma e-conomicVisma
Leading cloud accounting in Denmark and Norway with strong adoption among SMBs and accounting firms.
Visma eAccountingVisma
Cloud accounting for SMBs in Norway, the Netherlands and Sweden, where it is sold under the Spiris brand.
SpirisVisma
Cloud accounting for Swedish SMBs, formerly SPCS. The Visma eAccounting system under its Swedish name, reached through the same API.
Dinero
Danish accounting software for small businesses covering bookkeeping and invoicing.
Dynamics 365 Business CentralMicrosoft
Microsoft's cloud ERP for SMBs covering financials, supply chain and operations in more than 160 countries.
odoo
Open-source ERP used in more than 100 countries covering accounting, inventory, CRM and e-commerce.
Qonto
European business finance platform covering business accounts, expense management and invoicing.
Coming soonSAP Cloud ERPS/4HANA Cloud
Cloud ERP covering finance, supply chain, procurement and real-time analytics.
Coming soonBMD Software
Business software for accounting, payroll, ERP and document management, used by tax advisors and SMBs across the DACH region.
Coming soonSage 50 SpainSage
ERP and business management software built for Spanish SMBs.
Coming soonFatture in CloudTeamSystem
Cloud invoicing and accounting for Italian SMBs and freelancers.
ProcountorFinago
Cloud financial management by Finago, used across Finland, Sweden and Norway.
Don't see the system you need?
Maesn prioritises new systems by customer demand. Tell us which one your customers run.
The second integration is where in-house stops scaling
The first integration is usually the one a team underestimates least. It is the second, fifth and twelfth that reshape the roadmap. Each system brings its own authentication, its own pagination and filtering rules, its own error semantics and its own release cycle, and each one keeps needing attention long after it ships. Maintenance does not scale with your team, it scales with the number of systems your customers run.
Connecting through the Unified API moves that work off your roadmap. Breaking changes in an underlying system are absorbed on Maesn's side, new systems arrive on the interface you already built against and the depth per system stays Maesn's responsibility rather than a backlog item. What that coverage costs is set out on the pricing page.
That is also what makes integration coverage a sales asset instead of a support cost. A prospect asking whether you support their ERP is asking a commercial question. With one connection behind you, the answer covers 30+ systems rather than the one you happened to build first.
Every integration runs on European infrastructure.
Maesn is built and hosted in Germany. API calls are processed in real time and passed between your system and the target platform without storing customer data, and the platform is ISO 27001 certified and GDPR compliant. For customers in regulated industries that is usually what turns an integration question into a procurement approval.
