GoBD-compliant invoice archiving means keeping every invoice you issue or receive unchanged and retrievable for the statutory retention period — 8 years for invoices under §147 AO and §14b UStG — in a system where issued documents can be neither edited nor deleted. The GoBD ("Grundsätze zur ordnungsmäßigen Führung und Aufbewahrung von Büchern, Aufzeichnungen und Unterlagen in elektronischer Form sowie zum Datenzugriff") are the German tax administration's binding rules for digital bookkeeping. For a Shopify merchant they answer three questions: how long invoices must be kept, what "unchangeable" really means, and how to prove your process is orderly. This guide covers all three — plus the GDPR tension every merchant eventually asks about.
How long: the retention rules
Retention periods live in §147 AO (Abgabenordnung, the general tax code) and, specifically for invoices, §14b UStG. A significant change is recent: the Viertes Bürokratieentlastungsgesetz (BEG IV) shortened the retention period for accounting documents — which includes invoices — from 10 to 8 years, effective 1 January 2025. Books, records and annual financial statements keep their 10-year period; commercial letters keep 6.
| Document type | Retention | Legal basis |
|---|---|---|
| Invoices (issued and received), booking documents | 8 years (10 before BEG IV) | §147 Abs. 3 AO, §14b Abs. 1 UStG |
| Books, records, inventories, annual financial statements | 10 years | §147 Abs. 1 Nr. 1, Abs. 3 AO |
| Commercial and business letters (sent and received) | 6 years | §147 Abs. 1 Nr. 2–3, Abs. 3 AO |
Three practicalities matter for a shop:
- The clock starts at year end. The period runs from the end of the calendar year in which the invoice was issued. An invoice from March 2026 must survive until 31 December 2034.
- Original format counts. Electronically issued invoices must be stored electronically in the format they were issued in. For a ZUGFeRD invoice that means the PDF/A-3 including its embedded XML; for an XRechnung, the XML itself. Printing an e-invoice and filing the paper does not satisfy §14b UStG.
- Uninstalling an app doesn't end the obligation. The duty attaches to you, the merchant. If your invoicing tool deletes your archive when you cancel, that is your compliance problem, not the tool's.
Immutable: what "unchangeable" actually requires
The GoBD require that records be kept so that they are unveränderbar — unchangeable. Concretely, an archived invoice may not be edited, overwritten or deleted during its retention period, and if anything about a record legitimately changes, the change must be logged so the original state remains reconstructible.
A folder of PDFs is not an archive
Invoices in a Dropbox folder, on a laptop, or in Shopify's file storage can be silently overwritten or deleted by anyone with access — which is exactly what the GoBD prohibit. Genuine immutability comes from the storage layer refusing changes. In modern practice that means write-once storage (WORM — write once, read many), such as object storage with Object Lock in compliance mode: once written, the file cannot be modified or deleted by anyone — not the merchant, not the vendor, not an administrator — until its retention period expires. This is the model Rechna uses: every issued invoice is written once to Object Lock storage with an 8-year retention, and there is deliberately no delete path.
Why you must never edit or delete an issued invoice
An invoice is a tax document the moment it is issued: it determines your VAT liability and your customer's input VAT deduction. If issued invoices could be quietly altered, an audit could trust none of them. The GoBD therefore also expect gapless, chronological invoice numbering — a missing number in the sequence suggests a deleted (possibly suppressed) invoice, and a Betriebsprüfung will ask about every gap.
Corrections: Storno and Gutschrift, never the eraser
Mistakes happen — wrong address, wrong amount, a return. The compliant path is never to change the original but to issue a new document that references it:
- Storno (cancellation invoice): reverses the original invoice in full, referencing its number. The original stays in the archive; the pair nets to zero.
- Gutschrift (credit note): credits part or all of the amount, for example after a partial return.
Both documents get their own numbers from the same gapless sequence and are archived under the same rules. The audit trail always shows what happened and when. (In EN 16931 e-invoice formats these carry their own type codes — see our ZUGFeRD vs. XRechnung guide for how the structured formats work.)
Verfahrensdokumentation: proving your process
The GoBD expect every business with digital bookkeeping to maintain a Verfahrensdokumentation — a written description of how documents are created, processed, stored and protected, detailed enough that an expert third party (in practice: a tax auditor) can understand the system in reasonable time. For a Shopify store it should answer, at minimum:
- What triggers an invoice (order paid? fulfilled? manual?) and what data flows into it;
- How invoice numbers are assigned and why the sequence is gapless;
- Where documents are stored, in what format, and what makes the storage immutable;
- How corrections are handled (Storno/Gutschrift), and who has which access;
- How the archive can be exported for an audit (the GoBD's data-access rules, Z1–Z3, entitle the auditor to machine-readable access).
Formally it is required of everyone, from Kleinunternehmer to GmbH; proportionality applies — a small shop's documentation can be short, but "none" is a finding. This is a document your Steuerberater should review; a good invoicing tool gives you a head start by documenting its part of the process. Rechna, for instance, ships a Verfahrensdokumentation starter template covering issuance, numbering, validation and the Object Lock archive, which you hand to your advisor to complete.
The GDPR tension: "delete my data" vs. "keep every invoice"
Sooner or later a customer invokes Art. 17 GDPR — the right to erasure — and asks you to delete everything, including their invoices. You must not comply with the invoice part, and the GDPR itself says so: Art. 17(3)(b) GDPR exempts processing that is necessary for compliance with a legal obligation. Retaining invoices for 8 years under §147 AO and §14b UStG is precisely such an obligation.
The clean handling: delete or anonymize customer data you hold outside the statutory documents (marketing profiles, accounts, notes), inform the customer that invoices are retained under a legal obligation and blocked from other processing, and log the request and your reasoning. Your privacy policy should state this retention explicitly. The same logic governs Shopify's GDPR webhooks: when a customers/redact request arrives, operational data goes, statutory invoice archives stay — with the reasoning recorded.
The compliance checklist
| Requirement | Legal anchor | What to check in your setup |
|---|---|---|
| 8-year retention for all invoices | §147 AO, §14b UStG (BEG IV) | Archive keeps documents at least until 31 Dec of year of issue + 8 years |
| Original electronic format preserved | §14b UStG, GoBD | ZUGFeRD stored as PDF/A-3 with XML; XRechnung as XML — not as printouts |
| Immutability (no edit, no delete) | GoBD, §146 AO | Write-once storage (e.g. Object Lock, compliance mode); no delete path for anyone |
| Gapless, never-reused invoice numbers | GoBD; §14 Abs. 4 UStG (unique number) | Sequence has no gaps; numbering survives app changes and staff changes |
| Corrections only via Storno/Gutschrift | GoBD, §14 UStG | No "edit invoice" button anywhere in your process |
| Verfahrensdokumentation exists | GoBD | Written, current, reviewed with your Steuerberater |
| Audit export available | GoBD data access (Z1–Z3) | Period exports in machine-readable form (e.g. ZIP of documents + CSV index) |
| Erasure requests handled correctly | Art. 17(3)(b) GDPR | Invoices retained and blocked, rest deleted, decision logged |
What this means for a Shopify store
Shopify keeps order data for running your store — it is not a statutory archive, makes no immutability promise for invoice documents, and knows nothing of gapless invoice numbers or Verfahrensdokumentation. The archiving obligation sits entirely with you. You can meet it manually (disciplined exports, WORM storage you administer, documentation you write) or let your invoicing layer handle it. Rechna was designed archive-first: every invoice it issues is validated, numbered gaplessly, written once to Object Lock storage for 8 years with no delete path, and exportable per period as ZIP + CSV for your Steuerberater or an audit. If the mandate timeline is your next question, start with the complete 2027/2028 guide.
Rechna is software, not tax advice. Retention and documentation duties depend on your specific circumstances — review them with your Steuerberater.