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Rechnungskit

Sending invoices by email

Updated

Rechnungskit can send finished invoices to your customers by email automatically. Delivery is deliberately opt-in: by default, documents are only created and archived.

This page answers four questions: when an email goes out, which sender it comes from, which legal details it needs and what happens when sending fails.

When an invoice email goes out

You switch on automatic delivery under Settings → Email delivery with "Send automatically". From then on, every archived invoice goes to the customer right after it is created.

You can also send single invoices without this switch. The invoice view has a "Send invoice" button for that.

Automatic delivery
The email only goes out when everything is in place
"Send automatically" is offThe default. The document is created and archived.
Archive only
Test modeWhatever settings are active
Never sent
Legal details incompleteThe document is still created and archived
Task
No customer email addressNeither in the order nor in the payment
Task
Everything in placeInvoice attached as a PDF with embedded XML
Email goes out
Test mode creates no task, because holding the email back is the point there.

In test mode, no email ever goes out and no task is created either. If legal details or the customer's address are missing, the email is held back and you get a task. The document itself is created in every case.

Where the recipient address comes from

  1. From the order.
  2. If it is missing there, from the payment, for Mollie subscriptions the payer's address, for example.
  3. If there is no address anywhere, the invoice shows a note that no email address is available. Rechnungskit sends nothing. If automatic delivery is on, you also get a task.

Shops connected through the API send the address in the order's email field, for subscription follow-up orders too.

The sender is you

Invoice emails go out in your company's name, not in Rechnungskit's. The sender name is always your company name. The sender address depends on whether you enter your own mail server.

Through Rechnungskit (default) Your own SMTP server
Sender name your company name your company name
Sender address noreply@rechnungskit.de your own address
Your customers' replies to the reply-to address from Settings → Email delivery, otherwise to the contact email from your settings same
Setup none credentials under Settings → Email delivery, with a test send
Example · made-up company
Your customer sees your company either way
Through RechnungskitDefault
Display nameExample Roastery
Addressnoreply@rechnungskit.de
Setupnone
Your own SMTP serverOptional
Display nameExample Roastery
Addressyour own address
Setupcredentials with a test send
Either way, replies go to your reply-to address, otherwise to your contact email. Rechnungskit does not accept an unencrypted connection to your own mail server.

Your own mail server

Optionally, delivery runs entirely through your own SMTP server. These rules apply:

  • Hostname: you enter only the hostname, without https:// and without a path.
  • Reachability: the server must be publicly reachable.
  • Encryption: it must offer STARTTLS or TLS. Rechnungskit does not accept an unencrypted connection.

How to set up Gmail, Google Workspace or Microsoft 365 and what error messages mean is in the guide Setting up your own mail server (SMTP).

Legal details are required

The email is a business email of your company. That is why Rechnungskit requires complete legal details under Settings before sending.

Detail When required Note
Company name, street, postcode, city always
VAT ID or tax number always Only the VAT ID appears in the email signature, if there is one. The tax number is not published.
Register court, commercial register number, managing directors for registered companies As soon as one of these fields is filled in, all three must be complete.
Legal notice (Impressum), terms, privacy policy always linked in the email footer

Entering the register: under Settings you choose the register (HRB, HRA, GnR, PR or VR) and enter the number and the town of the local court (Amtsgericht), for example HRB, 25042, Montabaur. Below that you see how the line appears on the invoice: "Registergericht: Amtsgericht Montabaur, HRB 25042".

If something is missing: the email is not sent. The document itself is created and archived, and you get a task.

Asking the buyer for missing details

The data request email also goes out in your name. With it, the buyer adds their missing billing address. You trigger it with "Request details" on a task or automatically through the document rule "Email the buyer link automatically".

It needs at least your company name in the legal details. In test projects it is never sent.

Templates

You maintain subject and text per language (German/English) under Settings → Email delivery. There are three templates:

Template Used for Placeholders
Invoice every invoice {kunde}, {vorname}, {rechnungsnr}, {datum}, {betrag}, {firma}
Cancellation invoice the cancellation invoice (Storno) {kunde}, {vorname}, {rechnungsnr}, {datum}, {betrag}, {firma}
Payment request prepayment, before the invoice is created {bestellnr}, {betrag}, {firma}, {bankverbindung}
  • {vorname}: inserts the first name, as in "Hello Karola,". For business customers, or when no first name can be recognised, the full name appears there.
  • Payment request: it is worded neutrally, without the informal or formal German "you".
  • {bankverbindung}: inserts the account holder, IBAN, BIC and the order number as the payment reference, plus the fixed sentence "Dies ist keine Rechnung" (this is not an invoice). If the placeholder is missing from your text, Rechnungskit appends the block at the bottom.

When sending fails

Every failed send becomes an "Invoice email not sent" task, so nothing gets lost silently. That includes undeliverable addresses. The invoice itself is created and archived in every case.

Failed send
No failed send goes unnoticed
  1. Sending failsInvoice stays archivedwrong address, mail server or legal details, for example
  2. Right awayA task is created"Invoice email not sent", with the reason
  3. Youfix the causeand click "Resend"
  4. ThenThe task disappearsas soon as the send works

This is how it goes:

  1. The task names the reason, such as a rejected recipient address, a problem with your mail server or missing legal details.
  2. You fix the cause and click "Resend" in the invoice view.
  3. Once the send works, the task disappears by itself.

All reasons and how to fix each one are in the guide Resend an invoice email that was not sent.

Good to know

  • Attachment: the invoice is attached to the email as a PDF (with embedded XML).
  • No logo in the email: your logo appears on the invoice itself. The email stays deliberately plain, text plus legal footer, without an embedded logo.
  • Test mode: in test mode, emails are never sent, whatever settings are active.
  • Payment reminders: reminders for pay by invoice require active delivery.

Where to find it in the app

Rechnungskit is not a tax advisory or law firm. This article explains general principles and does not replace advice from a tax advisor (Steuerberater, § 5 StBerG) or a lawyer (§ 3 RDG). Rechnungskit is built for businesses based in Germany and prepares documents, tax rates and bookings automatically. How your specific case is treated remains your decision, ideally together with your tax advisor or a lawyer.

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