Integrate invoices by email

Set up the sender before the first invoice#

Complete these steps in the account profile before automating a mailbox or ERP rule.

1. Ask the Invoice-Converter team to enable the email channel for the Enterprise account.
2. Add the sending address and finish the verification link sent to that mailbox.
3. Choose whether replies return to the original sender or to a verified collective address, then select the reply language.
4. Copy the XRechnung and ZUGFeRD inbox addresses from the profile and test each required route with one representative PDF.

Select the target format with the recipient address#

From intake to reply#

Your message is accepted quickly; strict conversion then runs asynchronously and the results arrive as a reply.

1. A verified sender submits genuine PDF attachments to one or more format-specific inboxes.
2. The inbound provider records the message and the service resolves the enabled account, sender, reply destination, and selected target formats.
3. Each accepted PDF becomes a strict conversion task with artifact validation required and no draft or warning override.
4. The requested output is issued only after authoritative validation, persisted proof, and artifact-parity checks pass.
5. Threaded reply messages return issued artifacts and HTML reports; when attachments exceed the per-message size limit, delivery continues in additional messages, while message, item, usage event, proof, and durable reply files remain traceable by ID.

Billing units and email context#

Estimate the units for the whole message before sending, and remember that the email text itself is read as conversion input.

• Each accepted PDF consumes one conversion unit per matched target format. For example, two PDFs sent to both format inboxes require four units.
• Before conversion, the service reserves every unit in the message: first from the included monthly allowance, then from available API credits.
• If coverage is insufficient for all units, the whole message is rejected before conversion. A unit is only charged after its conversion succeeds and the reply artifacts are stored durably; failed units are released.
• If the email contains body text, the verified email subject and body are supplemental conversion input. They can supply missing amendments, corrections, references, or invoice facts. PDF monetary totals, tax totals, and invoice lines take precedence in conflicts, and body text alone cannot create invoice lines. Only a limited amount of body text is read and it may be truncated, so keep signatures and surrounding prose short, relevant, and unambiguous.
• Seller master data stored in your profile completes missing seller fields (name, address, VAT ID, contact) when default use is enabled; it never overwrites values extracted from the PDF.

Terminal outcomes and artifacts#

Accepted files and pilot limits#

Use these points as the practical checks for this section.

• Attach genuine PDF files. A renamed image or any other file type is rejected even if its extension or MIME type claims PDF.
• A message can contain multiple PDFs, but the channel is intended for controlled, low-volume workflows rather than bulk ingestion.
• Keep every attachment below the limit communicated during onboarding; provider and environment limits can change.
• If one message reaches more than one recognized format inbox, every accepted PDF is processed once for each selected format.
• Reply attachments are limited to roughly 15 MB per message. When the next file would exceed that limit, the remaining files are sent in another message in the same thread; an individual file is never split.

What still requires human review#

Use these points as the practical checks for this section.

• Compare supplier, buyer, invoice number, dates, currency, tax, totals, payment details, and every line with the source invoice.
• Confirm recipient-specific routing references, endpoint identifiers, purchase-order data, and delivery-channel rules.
• Review low-confidence source evidence and every warning or validation detail before sending the result onward.
• A successful technical validation proves the issued file against the selected rules; it does not replace commercial, tax, or recipient approval.

Choose email or the API deliberately#

Onboarding and support#

Share the expected sender addresses, target formats, reply destination, language, and monthly volume during onboarding.

Flow diagrams#

The diagrams summarize the same contract as the searchable sections above.