Which Lexware versions are supported?

We support the common Lexware product lines – including Lexware buchhaltung, Lexware financial office and the ERP variant. The specific integration path depends on your installed version and whether you use the desktop or cloud-based variant. In a free initial consultation, we clarify which technical approach is the most stable for your situation.

How long does a typical Lexware integration project take?

Simple integrations with standard document types (invoices, customer master data, payments) can be completed in four to eight weeks (project experience). More complex scenarios involving international tax treatment, historical data migration or multiple sales channels require proportionally more time for analysis and testing. After the requirements analysis, you receive a binding effort estimate.

Can historical shop invoices be transferred to Lexware retroactively?

A historical migration is technically possible. We recommend it when tax law requirements call for a complete document chain in Lexware, or when the accountant needs the history for reporting. Feasibility depends on data completeness in the shop and the desired migration period. We advise you openly on the effort and value of migration.

What happens when a transfer fails?

Failed transfers are automatically moved to an error queue, reported to the operations team via alert and logged. They do not block the processing of other documents. Once the cause is resolved (e.g. temporary Lexware unavailability), failed documents can be reprocessed. All steps are documented in an audit-proof manner.

Does the integration work with international shipping and different tax rates?

Yes. Our integration layer handles domestic transactions (19%/7%), intra-community deliveries to B2B customers with a valid VAT ID (tax-exempt, correct account assignment), EU-B2C under the One-Stop-Shop procedure and third-country transactions. The tax logic is configured once and then automatically applied to every document. VAT ID verification can be integrated into the connection.

Can the Lexware integration be extended with additional functions later?

Yes, our integration architecture is modular. You can start with invoice transfer and later add payment matching, credit note processing or a dual-export layer for DATEV. Connecting additional systems – such as an ERP inventory system or a central middleware – is possible without fundamental restructuring.

Lexware Integration: Invoices and Documents Flow Automatically from Your Shop

No more manual exports and duplicate data entry: we connect your online shop bidirectionally to Lexware. Invoices, customer master data, payment receipts and credit notes synchronize automatically – for clean accounting without rework.

Discuss Lexware project All services

Lexware accounting Automated document flow GDPR-compliant data transfer

50+

Accounting integrations

3–8 h

Time saved per month (project experience)

100%

Automated document flow

Duplicate entries after go-live

Lexware is one of the most widely used accounting solutions among German small and mid-sized businesses. When an online shop is added, a manual bridge quickly develops: CSV exports, copy-paste from the shop backend, manual matching of payments to open items. These bridges cost time, create errors and grow proportionally with order volume. Our integration solutions replace the manual effort with a reliable, automated connection between shop and Lexware. Whether Shopware CE, WordPress with an e-commerce extension, TYPO3 or a custom system – we know the integration scenarios and implement the right solution.

Network architecture of the Lexware integration: shop, integration layer and accounting in automated data flow.

What the Lexware integration concretely automates

A professional Lexware integration is not a single interface but an interplay of coordinated data flows. Invoices, customer master data, payments and credit notes must be transferred reliably and in the correct order. The following six functional areas cover the entire commercial document cycle that arises between the shop and Lexware.

Invoice Transfer

Every shop order automatically generates an outgoing invoice in Lexware. Invoice number, line items, tax rates, amounts and payment terms are correctly adopted. PDF documents are linked and stored in the Lexware archive.

Customer Master Synchronization

New shop customers are automatically created as debtors in Lexware. Address data, payment terms and customer numbers are taken from the shop and updated when changed. Duplicate debtors are prevented through deduplication logic.

Payment Matching

Payment receipts from the shop – whether advance payment, SEPA direct debit or credit card – are matched to open items in Lexware. Open item status updates automatically; dunning runs for already-paid invoices are blocked.

Credit Notes and Cancellations

Returns, partial credits and cancellations in the shop automatically create the corresponding documents in Lexware. The link to the original invoice is preserved, making the document cycle fully traceable.

Tax and Account Logic

Revenue accounts, tax rates and cost centers are assigned rule-based. Domestic, EU-B2B with VAT ID, EU-B2C and third-country transactions are handled correctly. Account assignment rules are configured once and then applied fully automatically.

Logging and Monitoring

Every transfer is logged. Failed transfers enter an error queue and trigger an alert without blocking the overall process. The operations team maintains a clear view of transfer status at all times.

How the Lexware integration works technically

Lexware offers different access paths for external integration depending on the product version. Our integration layer uses the optimal approach in each case and encapsulates the technical details behind a stable interface. The result is a robust data flow that continues to function reliably through Lexware updates and shop updates alike.

Lexware product variants and their integration paths

Depending on your Lexware variant (buchhaltung, financial office, ERP), we use different integration approaches: XML import interfaces for posting batches, DATEV import format (Lexware supports DATEV-compatible formats), direct database access for local installations or REST APIs for cloud-based variants. In an initial analysis conversation, we determine together which path is the technically most stable for your Lexware version and your shop platform.

Project workflow: From analysis to automated regular operations

Schritt 1

Analysis and inventory

We capture your Lexware version, your shop system and existing accounting processes. Which document types arise? How are revenue accounts and tax codes structured? Which payment methods are used? We clarify these questions together with you and – where relevant – with your tax advisor.

Scope: What the Lexware integration covers and what it does not

An honest description of the service scope is important to us so that your expectations align with the actual outcome. The Lexware integration automates the document flow between the shop and accounting software – it does not replace a full ERP solution. If you need inventory management, order control or supplier integration in addition to accounting connectivity, we recommend a more comprehensive ERP inventory integration or a central middleware solution.

Automatic transfer of outgoing invoices from the shop to Lexware
Creation and updating of debtor master data
Payment matching and open item maintenance in Lexware
Credit notes, partial credits and cancellation bookings
Rule-based account assignment by product group, customer type and tax scenario
Logging of all transfers with error alerting
Compatibility with Shopware CE, WordPress, TYPO3, Drupal and custom developments

Not in scope for Lexware integration (requires extension)

Inventory management and goods receipt bookings (→ ERP inventory integration)
Supplier management and incoming invoices
Full order control and production planning
Marketplace document flows from platforms like Amazon or eBay (→ marketplace integration)

Lexware integration in the context of your system landscape

The Lexware integration is often part of a larger integration architecture. Companies that operate both an online shop and branches, internal customer service or additional sales channels need a central integration layer that coordinates all data flows. In such scenarios, we recommend building a dedicated middleware that connects the shop, Lexware and other systems, serving as a single source of truth for document data.

If you also want to optimize your payment integration and automatically transfer payment provider data to Lexware, both requirements can be addressed in a shared project. In an initial consultation, we analyze which integration approach fits your system landscape – without being committed to a specific solution path upfront.

Using Lexware and DATEV in parallel?

Some businesses use Lexware for ongoing accounting and pass year-end data to a tax advisor who works with DATEV. In this case, our integration layer can either feed Lexware directly or – when needed – build a dual-export layer that prepares data both for Lexware and in DATEV-compatible format. Talk to us about your specific scenario.

Typical challenges – and how we solve them

In our Lexware projects we regularly encounter similar challenges. The most common: diverging numbering systems between shop and Lexware. Debtor numbers in the shop do not match customer numbers in Lexware, article numbers differ, and payment methods are named differently. Our integration layer resolves these divergences through a mapping table that is configured once and then works transparently in the background.

Another common challenge is historical data. If a shop has been running for some time and is only now being connected to Lexware, the question arises: should historical invoices be migrated retroactively? The answer depends on your tax law requirements, the volume of data and the quality of historical records. We advise you openly and implement a migration where it makes sense – or recommend starting automated operations from a clean cutoff date.

Common mapping challenges and our solutions

Harmonizing numbering systems

Shop and Lexware number ranges for customers, products and invoices diverge in almost every project. Our integration layer resolves conflicts through configurable mapping tables.

Customer number mapping with automatic lookup by email and name
Prefix logic for invoice numbers (e.g. shop prefix to avoid collisions)
Article number cross-reference between shop SKU and Lexware item number

Handling tax scenarios correctly

Lexware knows domestic and international tax rates, but correct assignment must be configured. Incorrect account assignment only becomes visible at the year-end close or during a tax audit.

Domestic: 19% / 7% by product group, automatic
EU-B2B: VAT ID validation before tax exemption
EU-B2C and third-country: rule-based special account assignment

Measurable benefits of Lexware automation

Manual transfer of an invoice from the shop to Lexware takes two to four minutes per document depending on complexity (project experience). With 200 orders per month, that is six to thirteen hours of pure data entry work, plus time spent on error corrections, payment matching and queries. All of this effort disappears after go-live.

More than time savings: data quality as a competitive advantage

Automated accounting integrations significantly improve data quality. Manual entry errors are eliminated, account assignments are consistent and the monthly close can be completed earlier. For growing shops, this means: accounting scales with order volume without requiring additional staff for document entry. Contact us via our contact form to assess your automation potential.

The Lexware integration is one building block in a broader integration ecosystem. Many of our clients combine it with additional interface projects that complement each other synergistically. If you are looking for a complete overview of our shop integration services, you will find all service pages there.

DATEV Integration

If your tax advisor uses DATEV, we transfer invoices and posting batches in DATEV-compatible format directly. Ideal for businesses that use Lexware internally and DATEV through their tax advisor. More about DATEV integration.

ERP Inventory Integration

When inventory levels, delivery notes and goods receipts also need to be synchronized alongside accounting, the ERP inventory integration seamlessly complements the Lexware connection. More about ERP inventory integration.

Payment Integration

Automatically transfer payment provider data to Lexware: transactions, fees and payouts are transferred as bookings and matched against open items. More about payment integration.