It is therefore not the same as scanning paper documents.

The distinction is simple:

Scanning creates a file. Digital archiving creates a controlled system for preserving documents and their context.

Digital archiving is one part of a broader digital accounting environment.

Why a Folder Full of PDFs Is Not a Digital Archive

Imagine an invoice saved as: invoice_final2_corrected.pdf

The file exists.

But five years later, can you determine:

• where it came from,
• which version is authoritative,
• who reviewed it,
• who approved it,
• whether anything changed,
• which transaction or accounting entry it belongs to?

If not, you have electronic file storage.

You do not yet have a well-controlled digital archive.

The real value of archiving comes from connecting:

document + data + process history

What Does EU Law Require From Digital Invoice Storage?

There is no single European law that defines every detail of how every accounting document must be archived.

For VAT invoices, however, EU legislation establishes several important common principles.

Under the EU VAT Directive, the authenticity of the origin, integrity of the content and legibility of an invoice must be maintained from issuance until the end of its storage period.

Authenticity of Origin

The company must be able to establish who issued the invoice.

This does not necessarily mean that every invoice requires an electronic signature.

EU rules allow businesses to use business controls that create a reliable audit trail between an invoice and the underlying supply of goods or services.

Integrity of Content

The required invoice content must remain protected against unauthorised alteration.

If information changes during processing, the company should still be able to understand what happened and preserve the required evidence.

Legibility

The invoice must remain readable throughout the relevant storage period.

This becomes particularly important in long-term digital storage.

It is not enough to save a file today if the company cannot reliably retrieve and read it years later.

What Is Harmonised Across the EU — and What Is Not?

This is where the old version of this article was too simplistic.

There is no universal EU rule saying that accounting documents must be kept for five, seven or ten years.

Individual Member States determine invoice retention periods and can impose additional national requirements.

For an international company, this has a practical consequence:

retention policy cannot simply be copied from one country to another.

A digital archive should allow retention rules to be configured according to document type, company and jurisdiction.

How Long Should Accounting Documents Be Kept?

The correct answer for an EU-wide audience is:

It depends on the Member State and the type of document.

The EU VAT Directive explicitly leaves the invoice-storage period to individual Member States.

National accounting and tax rules can then impose additional retention requirements for:

• invoices,
• accounting books,
• tax documentation,
• contracts,
• payroll records,
• employment documentation,
• corporate records.

Companies operating in several markets should therefore create a retention matrix based on the jurisdictions in which they operate.

Do not rely on a generic rule such as:

“Delete everything after ten years.”

The correct retention period may differ by country and document category.

What Is a Qualified Electronic Archiving Service Under eIDAS?

European rules around electronic archiving have also evolved.

The updated eIDAS framework introduced electronic archiving as a recognised trust service.

Under the Regulation, electronic archiving means a service that handles the receipt, storage, retrieval and deletion of electronic data or documents while preserving:

• durability,
• legibility,
• integrity,
• confidentiality,
• proof of origin.

The Regulation also defines qualified electronic archiving services.

A qualified service is provided by a qualified trust service provider and must meet additional requirements designed to preserve data and documents throughout the required legal or contractual preservation period.

Documents preserved using a qualified electronic archiving service benefit from a legal presumption regarding their integrity and origin during the preservation period.

Digital Archiving Should Not Start After Accounting Ends

A common mistake is to imagine the process as:

process → post → archive somewhere

A digital archive should instead be connected with the entire document lifecycle.

For example, an invoice may move through:

receipt → extraction → validation → approval → accounting context → ERP → archive

During that process, important information is created:

• when the document arrived,
• where it came from,
• who reviewed it,
• who approved it,
• what information changed,
• which exception was handled,
• when it was transferred to accounting.

If the company archives only the final PDF, much of that context disappears.

Digital archiving therefore belongs inside the broader accounting automation architecture.

What Should Modern Digital Archive Software Be Able to Do?

Archive Documents Automatically

Users should not have to complete the accounting process and then remember:

“Now I need to save this somewhere.”

Archiving should be integrated naturally into the document workflow.

Make Documents Easy to Find

A document should be searchable using information such as:

• supplier,
• invoice number,
• date,
• document type,
• project,
• cost centre,
• accounting metadata.

An archive that technically contains a document but makes it difficult to retrieve solves only half the problem.

Preserve Documents Together With Data

An invoice is more than an image.

It contains structured information such as:

• supplier,
• amounts,
• VAT,
• dates,
• due date,
• invoice number,
• accounting context.

Connecting documents with their metadata improves both retrieval and downstream processing.

Manage Access Rights

Not every employee needs access to every financial document.

A digital archive should therefore support user roles and permissions.

Preserve Process History

For financial documents, knowing what the document looks like today is often not enough.

Companies may also need to understand:

• who worked with it,
• who approved it,
• what changed,
• when events occurred.

Connect With Accounting and ERP Systems

The archived document and accounting record should not exist as two unrelated objects.

A connected process links the document, extracted data, approval history and accounting entry.

Audit Trail, Electronic Signature and Timestamp: What Is the Difference?

These concepts are often mixed together.

They solve different problems.

Electronic Timestamp

A timestamp can provide evidence that specific electronic data existed at a particular time.

Electronic Signature

An electronic signature is used primarily to connect a signer with electronic data and to support verification of the signature.

Depending on the type of signature and the applicable law, it can have different legal effects.

Audit Trail

An audit trail records what happened during a process.

It can show, for example:

• when a document entered the system,
• who approved it,
• what was changed,
• when it moved to the next stage.

An audit trail is therefore particularly important for internal financial control.

Why Is Digital Archiving Important During an Audit?

During an audit, the question is rarely only:

“Do you have the invoice?”

The auditor may also need context:

• Who approved it?
• Which process did it follow?
• Was anything changed?
• Which transaction or accounting entry belongs to it?
• Where is the supporting documentation?

If documents, emails, approvals and accounting data are distributed across several systems, audit preparation becomes a manual investigation.

A good digital archive helps the company answer a more useful question:

Can we reconstruct what happened?

Physical Storage vs Poorly Designed Digital Storage

Paper archives have obvious weaknesses.

Documents can be:

• lost,
• damaged,
• destroyed,
• filed incorrectly,
• available only in one physical place.

But digital does not automatically mean safe.

A poorly designed digital repository can still suffer from:

• weak access controls,
• nclear document versions,
• missing backups,
• inability to demonstrate changes,
• incorrect retention or deletion rules,
• loss of context between a document and accounting data.

The right comparison is therefore not simply:

paper vs cloud

It is:

uncontrolled storage vs controlled archiving.

How to Implement Digital Archiving Step by Step

1. Map the Documents

Identify:

• which document types the company processes,
• where they come from,
• where they are currently stored,
• who uses them,
• which laws apply to them.

2. Define Retention Rules

Do not create one retention period for every document.

Build rules by:

• document type,
• legal entity,
• country,
• applicable legislation.

For international companies, this is one of the most important design decisions.

3. Define Access Rights

Access should reflect actual responsibilities.

Finance, management, accountants and auditors may require different levels of access.

4. Decide How Documents Enter the Archive

The best archive does not begin with a manual Upload to archive button.

Documents should enter the archive naturally as part of their normal workflow.

For example:

invoice received → validated → approved → accounting data prepared → archived

5. Connect Documents With Accounting Data

Avoid two disconnected worlds:

file in archive + accounting entry in ERP

Create one connected process instead.

6. Start With One Document Category

Incoming invoices are often a practical pilot because they have:

• relatively high volume,
• a clear workflow,
• accounting relevance,
• long-term retention requirements.

7. Test Retrieval

Imagine a tax authority or auditor asks for one specific invoice several years from now.

Can you find it quickly?

Can you also explain its history?

If not, the archive is not finished.

The Most Common Mistake: Creating a Digital Filing Cabinet

A company removes its paper binders.

They are replaced with:

• folders,
• subfolders,
• more subfolders,
• file names,
• manually maintained rules.

The paper disappeared.

The process did not.

That is not genuine digitalisation.

A digital archive should reduce the number of manual decisions required to store and retrieve a document.

How Does E-Invoicing Change Digital Archiving?

Structured e-invoicing changes the object being archived.

Historically, companies often thought of an invoice as a visual document:

paper → PDF

With structured e-invoicing, an invoice increasingly becomes machine-readable data.

That raises a broader question.

What needs to be preserved:

• the visual representation,
• the structured invoice data,
• related attachments,
• evidence of authenticity and integrity,
• processing history,
• accounting context?

The precise legal answer depends partly on the Member State and applicable rules.

Operationally, however, finance teams should design archiving around documents, data and context, rather than treating the invoice as a standalone PDF.

Across Europe, this becomes increasingly important as structured e-invoicing expands and ViDA pushes financial processes further towards machine-readable data.

Read more in our guide to Peppol and e-invoicing in Europe.

How Does Wflow Fit Into Digital Archiving?

In Wflow, archiving is connected to the wider accounting process.

Documents can move from receipt through AI-supported extraction and approvals into the accounting or ERP environment and remain stored together with relevant process context.

Wflow supports areas such as:

• digital document storage,
• search and filtering,
• timestamps,
• process history and audit trail,
• ser access rights,
• connection with accounting and ERP systems through ready-made integrations and an open API.

The archive therefore does not need to be an isolated endpoint.

It can remain part of the document lifecycle.

Want to Move From File Storage to a Controlled Digital Archive?

You do not need to migrate every historical document at once.

Start with one process — for example incoming invoices — and ensure that new documents are captured, processed, connected with accounting data and archived correctly from the beginning.

FAQ

What Is Digital Archiving?

Digital archiving is the controlled long-term storage of electronic documents and data so that they remain accessible, readable, protected and traceable throughout the required preservation period.

How Long Do Accounting Documents Need to Be Archived in the EU?

There is no single retention period for all EU countries.

For VAT invoices, the EU VAT Directive allows each Member State to determine its own storage period.

Other accounting, tax, corporate and employment documents can be subject to different national retention rules.

Can Accounting Documents Be Stored Electronically?

In general, electronic invoice storage is recognised under EU VAT rules.

Companies must still comply with the applicable national requirements regarding retention periods, formats, accessibility and evidential requirements.

Does EU Law Require Electronic Signatures on Archived Invoices?

No general rule requires every invoice to carry an electronic signature.

Under the EU VAT Directive, authenticity and integrity may also be supported by business controls that create a reliable audit trail between an invoice and the underlying transaction.

What Is a Qualified Electronic Archiving Service?

Under the updated eIDAS framework, a qualified electronic archiving service is provided by a qualified trust service provider and meets specific requirements for preserving electronic data and documents.

Documents preserved through such a service benefit from a legal presumption regarding their integrity and origin during the preservation period.

Is a PDF Folder in Cloud Storage a Digital Archive?

Not necessarily.

A folder can store documents, but a proper archive also needs to address retrieval, access rights, integrity, retention, process history and connection with the underlying business or accounting context.

What Is an Audit Trail?

An audit trail is the recorded history of events associated with a document or process.

It can show who processed or approved a document, what changed and when individual actions occurred.

What Is the Difference Between Digitalisation and Digital Archiving?

Digitalisation converts paper-based or manual information into electronic documents and structured data.

Digital archiving focuses on preserving those documents and data over time while maintaining their accessibility, integrity and traceability.

Sources

European Commission: VAT Invoicing

EUR-Lex: Council Directive 2006/112/EC on VAT, Articles 233 and 244–249

EUR-Lex: Regulation (EU) 2024/1183, European Digital Identity Framework / eIDAS

EUR-Lex: Implementing Regulation (EU) 2025/2532 on qualified electronic archiving services

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E-Invoicing Is the Beginning. What Internal Process Comes Next?

E-invoicing changes the way an invoice arrives in a company.

Instead of a PDF attachment in an email, it can arrive as structured data that a system can read and process automatically.

That is a major step.

For financial management, however, an equally important question is what happens to the invoice after it arrives.

Who checks it? Who approves it? Who adds the cost centre, project or accounting context? Where are duplicates, suspicious bank-account changes or missing purchase orders detected? And when do the data reach the ERP so finance can actually work with them?

Across Europe, the regulatory journey differs by country. Some Member States already require structured domestic e-invoicing, others are introducing it gradually. At EU level, ViDA will make e-invoicing the basis for digital reporting for relevant cross-border B2B transactions from 1 July 2030. Taxation and Customs Union

If you are still getting familiar with the basics, start with E-Invoicing in the EU: How Peppol Works and Why It Is About Data, Not Documents.

Here, we will look at the next step: the internal process after the invoice arrives.

The Process Does Not End When the E-Invoice Arrives

A structured invoice improves the quality of incoming data.

But it does not create the rules inside your company.

That is why the transition to e-invoicing is a good opportunity to look not only at invoice format, but at the entire document flow from receipt to accounting.

Email Is Not an Accounting Workflow

Email can receive an invoice.

It cannot manage a financial process.

It does not know who should approve an invoice. It does not check whether it matches a purchase order. It does not automatically flag a changed supplier bank account. It does not know that an invoice has been stuck with one person for five days.

And when an auditor or CFO needs to find out exactly what happened to a document, an email thread quickly stops being sufficient.

If approvals are currently scattered across email, chats and informal agreements, see how automated invoice processing can connect approval, data extraction and accounting workflow.

What Should Happen After an Invoice Arrives?

Once an invoice arrives, the document needs to be classified, its type identified, data completed or validated, routed to the right approver, checked for exceptions and prepared for transfer to the accounting or ERP system.

At Wflow, we automate this process through several layers:

1. Smart Inbox‍

Invoices and documents enter one controlled place instead of remaining scattered across emails, folders and other channels.

2. Classification and Categorisation‍

The system identifies the document type, supplier, client or other context and prepares the document for the next step.‍

3. Data Validation and Exception Checks

‍Better input data do not mean zero risk. Documents still need to be validated, compared and checked for inconsistencies before they reach accounting.

4. Rule-Based Approval

An invoice should automatically reach the right person based on amount, supplier, project, cost centre or type of expense.

5. Transfer to Accounting / ERP

The ERP remains the accounting backbone. Wflow manages the process before the approved and validated data enter the accounting environment.

For companies that want to introduce e-invoicing without replacing their existing systems, see How to Implement E-Invoicing Without Replacing Your ERP.

E-Invoicing and Wflow Accounting Autopilot

E-invoicing improves the input.

Accounting Autopilot manages what happens next.

Its purpose is not to let AI post accounting entries without oversight.

The goal is to move routine work from accountants’ desks into a controlled workflow: collecting documents, classifying them, extracting data, validating information, preparing accounting suggestions and identifying the cases where human input is required.

The accounting team therefore does not need to treat every document in the same way.

Routine cases can move faster, while attention shifts towards exceptions, control and decisions.

You can see the complete workflow in Accounting on Autopilot: AI Takes Over Routine Document Processing.

The boundary between automation and human responsibility is just as important. We cover it in detail in AI in Accounting and Responsibility for Errors.

How to Tell That Your Process Is Not Ready

E-invoicing will expose weaknesses that already exist inside the company.

The warning signs are usually simple:

• invoices get lost in inboxes,
• approvals depend on reminders,
• the accounting team still re-keys data manually,
• the CFO sees liabilities too late,
• it is unclear who approved what,
• exceptions are handled differently every time,
• ERP data only become available when it is already too late to react.

If several of these sound familiar, the problem is not the invoice format.

It is the process around the invoice.

Traceability is especially important: who approved the document, what changed, why it changed and when it moved to the next stage should not depend on somebody finding the right email.

That same principle becomes even more important as more of the process is automated. See AI in Accounting and Responsibility for Errors for more on auditability and human control.

What to Prepare Before E-Invoicing

Before introducing e-invoicing, it is worth setting up several practical things.

Not to make the process more complicated, but to ensure that a structured invoice does not simply end up in the same chaos as today’s PDFs.

• One controlled entry point for all invoices

The principle is simple: invoices should not end up in personal email accounts, random folders or several disconnected team inboxes.

The company needs one place where documents enter and where it is immediately clear what arrived, who sent it, who it belongs to and what stage it is in.

• Expense rules before the invoice arrives

E-invoicing does not solve only the invoice itself.

If the company does not know who can order a service, who approves the expense, which project it belongs to or which budget it consumes, the delay simply moves further down the process.

A prepared company manages the whole expense process, not only invoice receipt.

• Rule-based approvals instead of reminders

An invoice should automatically go to the right person based on amount, supplier, cost centre, project or expense type.

Without these rules, even a structured invoice will get stuck in exactly the same place as a PDF: someone still needs to forward it, chase an approver and explain what needs to happen.

• Checks for duplicates, changed details and suspicious cases

Automation or Accounting Autopilot can perform part of this control, but the company still needs to define what it expects the system to check.

Duplicate invoices, supplier bank-account changes, purchase-order mismatches or unusual amounts should not depend solely on the manual attention of the accounting team.

• Clear exception handling

Standard cases can gradually move through the process faster.

That makes it even more important to define what happens when something is an exception: who deals with it, what information they need, how they decide and when the document returns to the standard workflow.

Otherwise, exceptions simply move outside the system again.

• Audit trail

Knowing that an invoice arrived is not enough.

The company needs to be able to trace who approved it, what changed and why.

Without an audit trail, control still depends on people’s memory and email history.

• ERP integration

The ERP remains the accounting backbone of the company.

Preparing for e-invoicing does not mean replacing it. The objective is to deliver clean, approved and traceable data into the ERP after the workflow before accounting has been completed.

E-invoicing can be introduced without replacing the existing ERP if the integration layer is designed correctly.

• Visibility of liabilities

Design the process so finance can see not only invoices that have already been posted, but also expenses and documents that are still awaiting approval or missing information.

This gives the CFO an earlier view of future liabilities — before they appear in the accounting system — and creates a better basis for managing cash flow and budgets.

E-invoicing sends better data into the company. Wflow helps build the process that knows what to do with them.

FAQ

What Should Happen After an E-Invoice Arrives?

After receiving an e-invoice, the company still needs to determine who takes ownership of the document, who checks and approves it, and how it is passed into accounting or the ERP.

E-invoicing improves input data, but internal workflows, approval rules, exception handling and audit trails still need to be designed separately.

Is It Enough to Receive E-Invoices by Email?

Email can deliver an invoice, but it cannot manage the entire financial process.

It does not manage approval rules, detect duplicates or changed information, handle exceptions or show where an invoice has become stuck.

If e-invoicing is to create genuine value, the company needs a controlled workflow around the structured invoice.

How Does Wflow Help Process E-Invoices?

Wflow helps manage what happens after invoice receipt: one controlled entry point, document classification, data validation, rule-based approvals, exception handling, an audit trail and transfer into the accounting or ERP system.

This means an e-invoice becomes more than a new document format. It becomes part of a controlled financial process.

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Accounting firms often grow by adding people. A new client means more documents, more communication — and sooner or later, another accountant.

This model is beginning to run into two fundamental problems:

• a shortage of qualified accounting talent,
• and a growing volume of routine work that keeps margins under pressure.

Across Europe, attracting and retaining accounting talent is already a structural challenge. ACCA describes longstanding skills and talent shortages in the profession, while its European talent research also points to considerable employee mobility and retention pressure. (source: ACCA Global)

But the capacity pressure on accounting firms is no longer just a recruitment issue.

Technology, automation and AI are changing which parts of accounting work genuinely require qualified people — and which parts can increasingly be handled by systems.

Value the Time of Scarce, Qualified People

Not every new client creates the same workload for an accounting firm.

One client delivers documents on time and in the right format. Another requires searching, reminders, manual sorting and repeated corrections.

All of this consumes accounting capacity that should be used for higher-impact work: ensuring accounting accuracy, resolving exceptions, improving data quality, checking VAT treatment, communicating with clients, preparing the close or explaining unusual costs.

The real capacity of an accounting firm therefore depends not only on the number of clients, but on how much manual work each client creates.

If accountants are difficult to recruit, the main question is no longer only “Where do we find another person?”

It is also: “What kind of work are we using the people we already have for?”

E-Invoicing Reduces Part of the Input Chaos

The EU defines an electronic invoice as an invoice that has been issued, transmitted and received in a structured electronic format that allows for its automatic and electronic processing.

For accounting firms, the crucial word is structured.

An invoice no longer has to arrive only as a PDF that somebody opens, reads and re-enters.

Increasingly, it can arrive as data that a system can read, validate and pass into the next stage of the process.

That can reduce some of the work that currently consumes accounting firms’ time:

• manually re-keying invoice data,
• checking data extracted imperfectly from PDFs,
• searching for basic information,
• sorting documents by client or accounting period,
• repeatedly correcting the same fields.

At EU level, EN 16931 provides the common semantic standard for structured e-invoices. ViDA will make EN 16931-based structured e-invoicing central to intra-EU B2B transactions from 1 July 2030, while domestic requirements can differ between Member States. (source: Taxation and Customs Union)

Peppol is important in this transition as one of the major infrastructures through which businesses and systems can securely exchange structured electronic invoices.

For an accounting firm, however, the practical impact matters more than the infrastructure itself: more invoices can arrive in a form that software can process earlier, more accurately and with less manual input.

Recommended reading

E-Invoicing in the EU: How Peppol Works and Why It Is About Data, Not Documents

See how Peppol is changing electronic invoicing in Europe and why moving from PDFs to structured data also changes financial processes themselves.

E-invoicing, however, cannot end with invoice delivery.

A structured invoice does not tell you whether an expense has been approved, which project it belongs to, who needs to provide context or whether the transaction represents an exception.

That is why the value of an accounting firm will increasingly lie in the process around the document, not simply in processing the document itself.

Where the Real Value of an Accounting Firm Lies

Accounting firms do not need to recruit more people simply so they can continue re-keying information, correcting the same errors and chasing clients for missing details.

They need to protect the capacity of qualified accountants for work that creates real value for the client.

E-invoicing can help by moving part of the input routine from accountants’ desks into the system: an invoice arrives as structured data rather than as a document that first needs to be manually interpreted.

Ardent Partners reported that the average AP organisation spent USD 9.40 to process a single invoice in 2024, including invoice receipt, processing, approval, people, technology and operating costs.

This is not a European accounting-firm benchmark, so it should not be read as one. But it illustrates an important principle: every manual intermediate step has a cost — and that cost multiplies with document volume.

A similar principle can be seen in the case of accounting firm SMEyo.

This was not an e-invoicing implementation. It was a digitalisation project for document processing with Wflow.

Documents stopped being manually sorted and physically searched for. Instead, they were automatically stored, extracted and prepared for further processing.

The result was a 70% time saving per document, allowing senior accountants to spend more time on professional work rather than invoice re-keying.  

What Accounting Firms Should Do Now

Preparing for e-invoicing does not have to begin with a technical implementation.

The first step should be an audit of the current process.

An accounting firm should map out for its clients:

• how documents arrive,
• how many channels each client uses,
• where information is missing,
• who approves expenses,
• which errors occur repeatedly,
• how much work happens before actual accounting begins,
• which steps should be handled by software.

The audit has one main purpose: identify where accountants’ time is being wasted unnecessarily.

Not everything can be automated immediately.

But it often becomes clear very quickly that a significant amount of work does not arise because the accounting itself is difficult. It arises because of poorly designed document flows between the client, approvers and the accounting firm.

Only then does it make sense to address automated document intake, classification, approvals, audit trails, exception handling and transfer into the accounting system.

For firms that want to go further than invoice intake alone, Wflow Accounting Autopilot shows how AI can automate routine document processing while keeping accountants in control of exceptions and decisions.

Wflow Makes Accounting Firms More Efficient

Wflow helps accounting firms reduce the amount of manual work between the client, the document and the accounting system.

Documents are collected in one place, automatically classified and enriched with the necessary context.

They are sent for approval, checked and passed on into the accounting process.

This means accounting teams spend less time searching through emails, chasing clients and manually checking which documents are ready for processing.

For the broader direction of this development, see also Accounting Routine Belongs to AI. Decision-Making Stays Human.

Want to find out where your accounting firm loses the most time before the actual accounting work even begins?

Let’s look at the document flow from your clients to the accounting system and identify where Wflow can help with intake, approvals, control and exception handling.