Connect DATEV with slimzaak
Work with a German accountant or Steuerberater who uses DATEV, or sell on German marketplaces like Kaufland and OTTO? Then you can connect slimzaak to DATEV in a few minutes via OAuth2. From that moment on, your customers, sales invoices and expenses flow through automatically as bookings, and your VAT return sits ready to be filed. slimzaak doesn't replace DATEV — it's the invoicing and admin tool that automatically pushes your Dutch VAT-compliant invoices and marketplace orders (bol.com, Amazon, Shopify, WooCommerce, Kaufland, OTTO) into your accounting software.
We deliver the bookkeeping entries to your package.
Invoice → slimzaak → DATEV
- 01
Connect
Connect your DATEV environment via OAuth2
You connect slimzaak to DATEV through a secure OAuth2 integration — no manual exports, no API keys to manage. Log in at DATEV, grant slimzaak access, and the connection is live. Together with your accountant, you then decide which bookings are allowed to flow through automatically.
- Secure OAuth2 connection, no passwords shared
- Set up in minutes from your slimzaak settings
- Works alongside your existing Steuerberater relationship
- Your accountant sees the same bookings back in DATEV
- 02
Sync
Customers, invoices and expenses booked automatically
Once the connection is active, slimzaak syncs with DATEV automatically. Your customers and contacts are created there, every sales invoice is pushed through as a sales booking, and expenses and receipts — which slimzaak already reads in automatically with AI scanning — land as a purchase booking. Nothing needs to be entered twice.
- Customers and contacts created automatically in DATEV
- Sales invoices pushed through automatically as sales bookings
- Expenses and receipts, already scanned with AI, as purchase bookings
- Orders from German marketplaces like Kaufland and OTTO too
- 03
VAT return
VAT data ready for your Steuerberater
slimzaak prepares your VAT return data in DATEV. You or your accountant file the return from DATEV itself with the tax authorities — slimzaak never files anything on its own, so control and responsibility stay with you and your Steuerberater.
- VAT return data automatically prepared in DATEV
- You file it yourself, or leave it to your accountant
- slimzaak never files returns on its own
Btw & OSSBtw & OSSFrequently asked questions
What exactly does the DATEV integration do?
Does slimzaak replace my DATEV bookkeeping?
Who files the VAT return with the tax authorities?
Who is the DATEV integration for?
Connect slimzaak to DATEV
Set up the OAuth2 connection and watch your first customers, invoices and expenses appear automatically in DATEV.
Free plan available · No credit card required