ERP Integration in B2B E-Commerce: SAP, DATEV, Dynamics

In B2B commerce, requirements differ fundamentally from B2C. Customer-specific pricing, complex discount structures, multi-level approval processes and recurring orders require a seamless data flow between online store and ERP system. Without this connection, information silos emerge that lead to delivery delays, incorrect pricing and unnecessary inquiries.

According to a Gartner study (2025), **78% of successful B2B merchants** already rely on automated ERP connections for their online stores. The reason: companies with integrated systems report **40% faster order processing** and a significant reduction in error rates during document capture (Forrester, 2024). For mid-market companies using [Shopware as their B2B platform](/en/shopware-development/), ERP integration is a decisive competitive factor.

[SAP Business One](/en/integrations/) is the most widely used ERP system in the German mid-market, with over **80,000 customers worldwide** (SAP, 2025). Integration with a B2B store requires a deep understanding of SAP data structures – particularly business partner hierarchies, price lists and document types. Via the SAP Service Layer API (OData-based), all relevant business objects can be synchronized bidirectionally.

Typical integration points include item master data with price lists and inventory quantities, business partners with delivery addresses and payment terms, as well as orders, invoices and credit notes. For Shopware-based [B2B portals](/en/services/), a middleware architecture has proven effective, acting as a mediation layer between the store API and SAP Service Layer. This middleware handles data validation, transformation and error handling.

Approximately **2.7 million companies** in Germany use DATEV for their financial accounting (DATEV, 2025). Integrating a B2B store with DATEV automates the entire document flow from order through invoice creation to posting. Manual CSV exports and re-imports are eliminated, and accounting always works with current data.

The DATEV interface is based on standardized formats such as the **DATEV posting batch** for journal entries and the **DATEV XML format** for online document exchange. Modern [integration solutions](/en/integrations/) additionally use the DATEV API for real-time synchronization of invoices and payment receipt notifications. Particularly relevant for B2B merchants is the automatic assignment of debtor numbers and the correct posting of different tax rates.

Automating the DATEV document flow typically saves trading companies **8–12 hours per week** in accounting effort. Furthermore, machine processing reduces the risk of erroneous postings that could lead to objections during tax audits.

Microsoft Dynamics 365 combines ERP and CRM functionality on a single platform, making it particularly attractive for B2B companies wanting to map customer relationships and merchandise management in one system. Around **500,000 companies worldwide** rely on Dynamics 365 (Microsoft, 2025). Integration with a [B2B online store](/en/services/) enables a 360-degree view of customer interactions – from the first inquiry in the store to recurring orders.

The connection is established via the [OData-based Dynamics API](/en/integrations/), which provides standardized access to all entities. For Shopware-based B2B stores, an event-driven integration model has proven effective: the store sends webhooks to the middleware for relevant events (order, customer registration, price inquiry), which transforms the data and forwards it to Dynamics. Conversely, Dynamics pushes changes to item master data or inventory quantities to the store via change tracking mechanisms.

Particularly valuable in the B2B context is the ability to leverage CRM data from Dynamics in the store. Field sales representatives see the same prices and availability in the CRM as the customer sees in the self-service portal. Quotes created in the CRM can be stored directly as order templates in the store. This consistency measurably increases sales efficiency.

Choosing the right integration architecture determines the maintainability, scalability and future-proofing of the entire solution. In practice, three approaches have been established: point-to-point connections, middleware-based integration and API hub solutions. For B2B scenarios with multiple systems to integrate, we generally recommend a [middleware approach](/en/integrations/) that serves as a central hub.

A central aspect of middleware architecture is **data transformation**. ERP systems and e-commerce platforms use different data models – an item number in SAP is not identical to the product number in Shopware. The middleware handles the mapping between these data models and ensures that information is transferred consistently and completely. Furthermore, the middleware layer enables a clean separation of systems: store updates or ERP upgrades can be performed independently, as long as API contracts are maintained.

An ERP integration project in a B2B environment typically follows a structured process that can be divided into five phases. The total duration depends heavily on the complexity of the existing IT landscape and the scope of processes to be integrated. For mid-market companies, project timelines of **8 to 16 weeks** for an initial integration are realistic.

ERP integration projects are demanding and carry specific risks. The most common challenges include inconsistent master data, historically grown data structures in the ERP and missing API documentation for older system versions. An upstream **data cleansing** effort is often the key to project success.

Another frequent issue is **performance with large data volumes**. B2B catalogs with 50,000 or more items and hundreds of customer-specific price lists require well-thought-out synchronization strategies. Instead of a complete data reconciliation, a **delta sync approach** has proven effective: only changed records are transferred, identified via timestamps or change tracking mechanisms of the ERP system.

**Multi-tenancy** is particularly relevant for groups and corporate entities. When multiple companies operate on a single [Shopware instance](/en/shopware-development/), the middleware must assign the correct ERP tenants and cleanly separate data. This affects item master data as well as customer data and document chains.

The ERP integration landscape is constantly evolving. Trend technologies such as **Event-Driven Architecture**, **GraphQL APIs** and **API-first approaches** open new possibilities for flexible and performant integrations. SAP is increasingly focusing on cloud-native integration with the SAP Business Technology Platform (BTP), while Microsoft provides a unified data platform for Dynamics 365 with Dataverse.

For B2B merchants, this means concretely: investing today in a **modern, API-based integration architecture** positions you well for future requirements. Connecting additional systems – such as a PIM system for product data management or a WMS for warehouse logistics – is significantly easier with existing middleware infrastructure than with point-to-point architecture. The investment in a solid [integration architecture](/en/integrations/) pays off in the long term through lower expansion costs and higher reliability.

The topic of **AI-supported data processing** is also gaining importance: intelligent matching algorithms can automate item mapping between systems, detect anomalies in synchronization data and continuously improve data quality. Combined with professional [monitoring](/en/services/), the integration solution can be proactively monitored and optimized.