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E-invoicing API for Germany and the EU

XRechnung, ZUGFeRD, and Factur-X: all EN 16931 compliant. Validate, send, and receive electronic invoices through a single REST API with EU/EEA-hosted primary service data.

Get started free See invoice docs

Everything the product needs. Nothing it does not.

A focused API surface with production controls, predictable resources, and the operational visibility to run email confidently.

01

XRechnung & ZUGFeRD validation

Validate invoice XML against the EN 16931 standard and the German XRechnung CIUS. Returns structured errors so you can fix and retry.

02

Send e-invoices by email

Deliver invoices as signed XML attachments or embedded PDFs (Factur-X). Full deliverability, bounce handling, and read receipts.

03

Receive and parse inbound invoices

Accept inbound invoices at a dedicated address and get structured JSON via webhook. Extract line items, totals, VAT, and buyer/seller IDs automatically.

04

EU/EEA-hosted primary service data

Primary invoice service data is hosted in the EU/EEA. Limited infrastructure metadata may be processed by providers under appropriate transfer safeguards.

05

2025–2028 mandate ready

Built for the German B2B e-invoicing mandate: receiving required from 2025-01-01, sending in phases through 2028. Test in the sandbox today.

06

Works with your ERP

Drop-in REST endpoints your existing billing system can call from any HTTP client. No vendor lock-in.

Start with one request.

The public API uses explicit resources and familiar JSON. Move from a first request to production without changing integration models.

See invoice docs
cURL: validate an XRechnung file ready
curl -X POST https://api.postscale.io/v1/invoices/validate \
  -H "Authorization: Bearer ps_live_..." \
  -H "Content-Type: application/xml" \
  --data-binary @invoice.xml

# Response
{
  "valid": true,
  "format": "xrechnung-ubl",
  "standard": "EN 16931",
  "profile": "urn:cen.eu:en16931:2017",
  "errors": [],
  "warnings": []
}

Further reading

01

XRechnung API: A developer's guide to Germany's e-invoicing mandate

What XRechnung is, what the 2025–2028 mandate requires, and how to send and receive EN 16931 invoices programmatically.

Read more
02

Moving from Resend for XRechnung support

Resend doesn't offer e-invoicing. If you're billing German B2B buyers, here's how the switch works.

Read more

Frequently asked questions

What is XRechnung and how does it relate to E-Rechnung?

E-Rechnung is the German umbrella term for electronic invoices. XRechnung is the specific XML format mandated for invoicing German public-sector buyers, based on the EU EN 16931 standard. Since 2025-01-01 all German businesses must be able to receive E-Rechnung; sending is being phased in through 2028.

Do you also support ZUGFeRD and Factur-X?

Yes. ZUGFeRD (Germany) and Factur-X (France) both embed a structured XML invoice inside a human-readable PDF. Our API validates, sends, and parses all three formats interchangeably.

Is the data processed in the EU?

Postscale is operated by DNScale OÜ (Estonia, EU). Primary invoice service data is hosted in the EU/EEA, with appropriate transfer safeguards for limited infrastructure metadata where required. We sign a standard GDPR DPA.

Can I test before committing?

Sign up free: no credit card. The sandbox supports full XRechnung validation and a limited number of real sends. Upgrade only when you need production volume.

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