FastBill E-Invoicing Review 2026: XRechnung, ZUGFeRD & DATEV Export Tested

FastBill has been a popular choice for German freelancers and micro-businesses since 2010. It sits between minimalist invoice tools and full accounting suites — easier than DATEV or Lexware, more capable than a basic invoice generator.

With Germany's 2027 sending mandate approaching, we tested FastBill's e-invoicing capabilities in detail. The result is a nuanced picture: strong for its target audience, but with a limitation that matters for the mandate.

Disclosure: This review is editorially independent. See our editorial policy.

At a Glance

Feature	Details
Product	FastBill Cloud Accounting
Website	fastbill.com
Founded	2010, Frankfurt, Germany
Target Users	Freelancers, sole traders, micro-businesses
Starting Price	€9.99/month
Free Trial	14 days (no credit card required)
XRechnung Support	✅ Native, version 3.0
ZUGFeRD Support	⚠️ Version 2.1 (not 2.3 EN 16931)
Peppol Support	🔜 Planned
DATEV Export	✅ Available
Our Rating	4.1 / 5.0

The Key Finding Upfront

FastBill supports XRechnung 3.0 (fully mandate-compliant) but generates ZUGFeRD version 2.1 rather than the current 2.3 standard. For freelancers and businesses planning to use XRechnung, FastBill is mandate-ready. For businesses preferring ZUGFeRD, the 2.1 output is not compliant with the German B2B mandate requirements — the mandate requires ZUGFeRD 2.3 EN 16931 profile.

We confirmed with FastBill's support team (April 2026) that ZUGFeRD 2.3 is on their roadmap for H2 2026. Until it ships, if you need ZUGFeRD specifically, consider sevDesk or easybill instead.

What Is FastBill?

FastBill is a cloud-based accounting tool for German freelancers and micro-businesses. Unlike pure invoicing tools, it includes:

Invoice creation and management
Expense tracking and receipt scanning
Bank account integration (Open Banking)
Offer and quote creation
DATEV export for tax advisors
Basic financial reporting

It is positioned as the "all-in-one for solopreneurs" — simpler than Lexware or DATEV, but more comprehensive than basic invoice generators.

E-Invoicing Setup

XRechnung 3.0 Setup (5 minutes)

FastBill's XRechnung implementation is straightforward:

Go to Settings → Invoice Settings → E-Invoice
Enable "Elektronische Rechnung (E-Rechnung)"
Select "XRechnung" as the format
Enter your business details (VAT ID, tax number)

When you generate an invoice, FastBill creates an XRechnung 3.0 XML file attached to the standard invoice email.

We validated the output with the KoSIT online validator — the result was clean: no errors, all mandatory fields present, correct buyer reference field (BT-10).

ZUGFeRD Setup

ZUGFeRD is available but generates version 2.1. The setup path is identical — select ZUGFeRD instead of XRechnung in the settings.

Important: We validated the ZUGFeRD output against the KoSIT validator. It passes for ZUGFeRD 2.1 but does not meet the ZUGFeRD 2.3 EN 16931 requirement for the German mandate. For current B2B invoicing to partners who can accept 2.1 (many older systems), this works. For mandate compliance from 2027, wait for the 2.3 update.

Banking Integration

FastBill's bank connection (via finAPI) is one of its strongest features. It connects to over 4,000 German banks and:

Automatically imports transactions
Suggests matches between bank transactions and invoices
Flags unpaid invoices past due date
Supports SEPA payment reference extraction from structured e-invoices

The SEPA integration with XRechnung is particularly smooth — when FastBill generates an XRechnung, it automatically includes your IBAN in the structured payment means field, enabling automated SEPA reconciliation on the recipient's side.

DATEV Export

FastBill's DATEV export is solid for straightforward cases:

Exports in DATEV ASCII format (the standard most German Steuerberater use)
Includes invoice amounts, dates, and tax codes
Can be scheduled for quarterly or monthly delivery to your tax advisor

Limitation: DATEV export is one-way (from FastBill to DATEV), not bidirectional. Your tax advisor cannot push corrections back into FastBill — manual reconciliation is required.

Mobile App

FastBill's iOS and Android apps are genuinely good — among the better mobile experiences in German accounting:

Create and send invoices from mobile
Scan receipts with OCR
View payment status and bank transactions
Receive push notifications for overdue invoices

The mobile app supports XRechnung attachment sending — useful for freelancers who invoice on the go.

Pricing

Plan	Price	Documents/month	Key Features
Solo	€9.99/month	Unlimited	XRechnung, ZUGFeRD, banking, DATEV export
Pro	€19.99/month	Unlimited	All Solo + multiple users, advanced reports

FastBill does not have a free tier. The 14-day free trial is generous for testing.

At €9.99/month, it is among the most affordable German accounting tools — cheaper than sevDesk (€8.90 but with a more limited free tier pathway) when you factor in features.

Comparison vs Competitors

Feature	FastBill	sevDesk	easybill
Price from	€9.99/mo	€8.90/mo	Free tier
XRechnung 3.0	✅	✅	✅
ZUGFeRD 2.3	❌ (2.1)	✅	✅
Peppol	Planned	Via plugin	✅ Native
Banking integration	✅ Strong	✅	Limited
DATEV export	✅	✅	✅
Mobile app	✅ Good	✅ Good	❌ No app

Verdict

FastBill is well-suited for:

Freelancers using XRechnung (fully compliant today)
Sole traders who want banking integration and DATEV export in one affordable tool
Businesses invoicing B2G (public authorities) who need XRechnung

FastBill is not yet right for:

Businesses that specifically want ZUGFeRD 2.3 EN 16931 mandate compliance (wait for their 2.3 update)
Companies needing Peppol access (currently planned but not available)
Businesses needing multi-user collaboration at low cost

Our rating: 4.1 / 5.0

The XRechnung support is mandate-ready. The ZUGFeRD limitation is a real gap for the 2027 mandate if you prefer the PDF+XML hybrid format. If FastBill ships ZUGFeRD 2.3 in H2 2026 as planned, the rating rises.

Last tested: April 2026. Prices and features current as of publication. Verify current pricing at fastbill.com.