Automate Dunning – Cut DSO by 21 days
Cut DSO by 14-21 days with automated dunning for Lexoffice, DATEV, or sevDesk. 70% fewer collections cases, § 286/288 BGB compliant, approval gates.
Dunning Workflow
Daily triggered run checks all open AR, escalates by rule across 4 stages (approval checkpoint from stage 3) and stops automatically on payment.
Before vs. After
| Aspekt | Before | After |
|---|---|---|
| Days Sales Outstanding (DSO) | ~50 days | ~30 days (-21 days) |
| First customer contact after due | 21+ days, inconsistent | Day 3 automated, friendly |
| Collections handoffs per year | ~40 cases × 20% fee | ~10 cases (-70%) |
| Finance time on dunning | 4-6h every Friday | ~30min approvals per week |
| Late fee calculation | Manual in Word, error-prone | § 288 BGB day-accurate |
| Audit trail under dispute | Patchy, Excel lists | GoBD-compliant, 10-year archive |
The Challenge
Overdue receivables are the silent liquidity killer in mid-market finance. A typical German B2B firm with 200-600 open invoices spends 4-6 hours every Friday pulling AR aging reports, drafting dunning letters in Word, calculating late fees and § 288 BGB interest, and documenting sends. Results are inconsistent: long-standing customers get forgotten or treated too harshly, new customers slip through, and average Days Sales Outstanding (DSO) sits at 45-60 days instead of the target 30. Soft costs compound: customers are surprised by dunning letters because first contact often comes 21+ days after due date. Legal exposure grows when § 286 BGB notice timelines aren't cleanly documented. Every collections handoff costs 15-25% of the receivable plus interest – money that earlier, more consistent outreach would usually have saved. Extrapolated: a company with €2M annual revenue and 50-day DSO ties up ~€275,000 more working capital than at DSO 30.
Our Solution
An orchestrated dunning workflow that plugs natively into your existing invoicing system – Lexoffice API, DATEV Unternehmen Online, sevDesk, or Billomat – and runs a daily AR check. Four configurable stages (friendly reminder, 1st dunning with new deadline, 2nd dunning with late fee and interest, final notice with collections warning) with customer-segment-specific escalation profiles. Long-standing high-credit customers get gentler tone and longer deadlines; new customers strict. Payment reconciliation runs in real time before every stage – no customer gets dunned for an already-paid invoice. Messages are AI-personalized (industry, invoice context, payment history) while preserving brand tone, with human approval gates from the 2nd stage onwards. Legal-grade deadline math per § 286 BGB, 10-year GoBD-compliant archival, and full GDPR audit trail built in. Optional self-service installment flow lets customers propose payment plans via a link, auto-configured in Stripe or GoCardless. Outcome: DSO drops 14-21 days, collections handoffs drop 60-80%, finance team reclaims 3-5 hours per week.
Key Features
Native Invoicing Integration
Direct integration with Lexoffice, DATEV Unternehmen Online, sevDesk, or Billomat – no dual entry, no CSV exports. AR is synced hourly.
Customer-Specific Dunning Profiles
Per segment (long-standing, new, enterprise, public sector): own escalation profiles with tone, deadlines, late fees, and path.
Real-Time Payment Reconciliation
Before each stage, the system checks current payments via bank API or invoicing system. Already-paid invoices drop out of the dunning queue automatically.
§ 286/288 BGB Auto-Calculated
Default onset, late fees, and statutory interest (5%/9% above base rate) calculated day-accurate and audit-safe. Notice timing verifiable in court.
Approval Gates from Stage 2
Reminder and 1st dunning run fully automated. From 2nd dunning (with late fee) onwards and before collections: human approval via Slack, Teams, or email link.
Installment Self-Service
1st dunning email includes a link for customers to propose installment plans themselves. Auto-configured via Stripe Billing or GoCardless SEPA mandates.
Results
DSO from ~50 to ~30 days, 60-80% fewer collections cases, 3-5h/week reclaimed
These figures indicate the expected magnitude of this reference architecture — based on industry benchmarks, public studies of comparable setups, and our own tests on real stacks. Actual results in live deployment vary with company size, process maturity, and integration depth.
Integrations
Seamless connection to your existing infrastructure
Lexoffice
Invoicing SystemNative Office API for AR, dunning stages, and payment reconciliation
DATEV Unternehmen Online
Invoicing SystemDATEVconnect integration for tax consultancies and mid-market on DATEV
sevDesk / Billomat
Invoicing SystemAlternative invoicing connection for SMB and freelancer portfolios
Stripe Billing / GoCardless
InstallmentsSelf-service installments via payment link, automated SEPA mandates
Brevo / Mailjet
Email DeliveryTransactional email with delivery receipts, open and click tracking
Slack / Microsoft Teams
Approval WorkflowApproval notifications with one-click approve for finance and management
Security & Compliance
Enterprise-ready with highest security standards
GoBD-Compliant Archive
Every dunning event archived immutably for 10 years with timestamp, recipient, text, approver. BMF Nov 2019 compliant.
GDPR & EU Hosting
Processing exclusively in EU data centers (Frankfurt, Munich). Art. 28 DPA, automated retention and access request processes.
§ 286/288 BGB Compliance
Default onset, late fees, and interest calculated audit-safe and day-accurate. Notice timing defensible in court.
Encrypted Communication
All dunning emails sent via TLS 1.3. DKIM, SPF, and DMARC configured to prevent phishing confusion.