Invoicing SAF-T vs. Accounting SAF-T: A Crucial Distinction

Confusion between the two types of SAF-T files is a common source of errors and, sometimes, penalties. It is imperative to understand their differences and respective legal obligations to avoid problems with the Tax and Customs Authority (AT).

• Invoicing SAF-T (PT): This file is already a consolidated reality and mandatory. Its origin dates back to Decree-Law No. 198/2012, of 24th August, which established the obligation for its communication. It is a monthly file that aggregates all sales documents (invoices, invoice-receipts, simplified invoices, credit and debit notes, and other fiscally relevant documents) issued. Its communication to the AT must be made by the 5th day of the following month of its issuance, electronically. Non-compliance with this obligation can result in significant penalties, according to the General Regime of Tax Infractions (RGIT), namely its article 123. This regime has been subject to several updates, but the essence of the invoicing SAF-T obligation remains unchanged. To delve deeper into this topic, consult our guide on ATCUD, QR code and invoicing SAF-T.
• Accounting SAF-T (PT): This is the central subject of this article and the focus of the latest postponement. It is an annual file that covers the entire accounting of the company, including the chart of accounts, all accounting movements, and trial balances. Its purpose is to allow the AT structured and detailed access to companies' financial information. Its mandatory nature, initially foreseen in Ordinance No. 31/2019, of 24th January, has been successively postponed, now applying to tax periods of 2027 and subsequent years, with the first submission scheduled for 2028, together with the Simplified Business Information (IES). It is essential to note that, unlike the invoicing SAF-T, which focuses on sales documents, the accounting SAF-T covers the generality of accounting operations, representing a substantially higher level of detail and complexity.

The correct distinction and compliance with both obligations are vital for the fiscal and accounting health of any entity.

The Legal Framework of Accounting SAF-T in the State Budget for 2026

The latest legislative amendment regarding accounting SAF-T was introduced within the scope of the State Budget for 2026 (OE2026). Although the final text of OE2026 is not yet published at the time of writing this article, preliminary proposals and parliamentary discussions confirmed the postponement. This postponement represents the ninth extension since the publication of Ordinance No. 31/2019, of 24th January, which regulates the data structure of the accounting SAF-T (PT) file. This ordinance establishes the elements of the file, its structure, and validation rules, being the basic document for its implementation.

According to the provisions of OE2026, the obligation to submit the accounting SAF-T file will apply to tax periods of 2027 and subsequent years. Consequently, the first submission of this file will occur in 2028, simultaneously with the submission of the IES for the 2027 period. It is crucial to note that the IES submitted in the current year (referring to 2025) and that to be submitted in 2027 (referring to 2026) will follow the previous rules, i.e., without the obligation to attach the accounting SAF-T file.

This cycle of postponements reflects the complexity of implementation and the challenges that companies and accounting professionals face in adapting their systems and processes. However, each postponement should be seen as an opportunity for more robust preparation and not as an invitation to inaction.

Why Early Preparation is Indispensable: Risks and Competitive Advantages

Ignoring accounting SAF-T until its entry into force is a high-risk strategy. When the obligation becomes effective, the AT will have access to an unprecedented amount of structured accounting data, allowing for a much deeper and automated analysis of companies' tax compliance. The implications are vast and can have a significant impact on the financial and reputational health of organisations.

Automated AT Analysis and SNC Taxonomies

The AT will receive the company's complete accounting in a standardised format, which will facilitate the validation of data against the taxonomies of the Accounting Standardisation System (SNC). These taxonomies, established by Ordinance No. 302/2016, of 2nd December, define the structure and classification of accounting accounts, ensuring uniformity in the presentation of financial information. In practice, this means:

• Detection of Accounting Classification Errors: Improperly used accounts, abnormal balances, or movements without robust documentary support will no longer go unnoticed. For example, the use of an operational expense account to record an investment in tangible fixed assets, or credit balances in customer accounts without justification, will be easily identified by the AT's algorithms.
• Automatic Pre-filling of IES: The quality of the underlying accounting information will directly determine the quality of the IES pre-filling. Disorganised or erroneous accounting will result in an incorrect IES, requiring time-consuming manual corrections and increasing the risk of tax inspections. The IES, regulated by the Corporate Income Tax Code (CIRC), in its article 121, and by the Value Added Tax Code (CIVA), in its article 29, is one of the most important documents for the AT.
• Data Cross-referencing and Automated Audits: The AT will be able to cross-reference data from accounting SAF-T with invoicing SAF-T, with periodic VAT declarations, with IRS/IRC declarations, and with other sources of information. This data cross-referencing capability drastically increases the effectiveness of tax audits and the likelihood of detecting inconsistencies and fraud.
• Risk of Fines and Penalties: The detection of irregularities can lead to the application of fines and compensatory interest, according to the RGIT. For example, the omission or inaccuracy of data in the IES can result in fines ranging from €250 to €2500, doubling in case of recidivism, according to article 120 of the RGIT.

The Cost of Inaction: Correcting Bad Practices in the Short Term

Correcting years of bad accounting practices at the deadline for submitting accounting SAF-T will be not only costly but also extremely complex and risky. The cost of rectifying past errors, reclassifying movements, and adjusting charts of accounts can be exponentially higher than the investment in proactive preparation.

Companies whose organised accounting already fully respects SNC taxonomies and best accounting practices will not face any shocks in 2028. These entities already have a competitive advantage, as their financial information is reliable and auditable. The others, on the other hand, will face the discovery of all their problems at once, with the additional pressure of deadlines and the scrutiny of the AT.

Practical Example 1: Financial Impact of Late Correction

Consider a company that, due to deficiencies in its accounting system and lack of alignment with SNC taxonomies, improperly recorded capital expenditures (investments) as current expenses over 5 years. Suppose the average annual value of these expenses was €10,000. The total of incorrectly classified expenses is €50,000.

• Immediate Tax Impact: The undue deduction of these "expenses" as operational costs instead of being capitalised and amortised means that the company paid less Corporate Income Tax (IRC) than due. Assuming an IRC rate of 21%, the company would have to regularise €50,000 * 21% = €10,500 in IRC.
• Compensatory Interest: To this amount are added compensatory interest at the legal rate (currently 4% per year, according to the Tax Benefits Statute (EBF), article 35, although the rate may vary). If the correction is made at the end of 2027 for the years 2022 to 2026, interest can accumulate for several years. For the year 2022, for example, it would be €10,000 * 21% * 4% * 5 years = €420. The total interest for the 5 years would be substantially higher.
• Fines: In addition to the missing IRC and interest, the company will be subject to fines for inaccuracy in the IRC declaration, which can range from 15% to 30% of the missing tax (article 114 of the RGIT). In the most favourable scenario (15%), it would be €10,500 * 15% = €1,575.
• Correction Costs: The cost of reprocessing and adjusting 5 years of accounting, including the accountant's time and eventual external audit, can amount to thousands of euros.

This example illustrates how inaction can transform an accounting problem into a heavy financial and administrative burden.

5 Essential Steps for Effective Preparation

Preparation for accounting SAF-T should be seen as a strategic project, involving various areas of the company. The following steps provide a clear roadmap to ensure a smooth and compliant transition:

1. Confirm that the chart of accounts is aligned with SNC taxonomies: This is the fundamental starting point. Your company's chart of accounts must be in strict conformity with the structure and account designations defined in Ordinance No. 302/2016, which approved the SNC taxonomies. An internal audit of the chart of accounts, comparing it with the official taxonomies, is the first step. Any deviation or use of unprovided accounts must be corrected, reclassifying existing balances.
2. Validate that the accounting software generates the accounting SAF-T: Most certified accounting software already has modules for generating accounting SAF-T. However, it is crucial not to assume this functionality. Contact your software provider to confirm the ability to generate the file in the required format and, more importantly, to understand the configuration requirements and necessary updates. Request a demonstration and confirm that the software is prepared for the latest specifications of Ordinance No. 31/2019.
3. Generate the test file with 2025 (or 2026) data and analyse validation errors: Do not wait until 2028 to test. Use accounting data from a previous period (e.g., 2025 or 2026, when available) to generate a test accounting SAF-T. Many software allows validating this file against AT rules. Meticulously analyse the validation reports to identify any errors or warnings. These may include inactive accounts with balances, movements in third-party accounts without proper NIF identification, or abnormal balances. This practice allows for timely correction and avoids surprises.
4. Correct problematic classifications now: Once errors and inconsistencies are identified through the test file, proceed with their immediate correction. This may involve reclassifying past movements, creating new accounts according to SNC taxonomies, or reviewing accounting registration procedures. Dragging bad practices for two more exercises will only aggravate the problem and increase the cost and complexity of future correction. The review and updating of internal accounting registration procedures are crucial to ensure continuous compliance.
5. Talk to your accountant about the topic: Your certified accountant is a strategic partner in this process. They should be aware of the latest legislative updates and have the technical knowledge to guide you. If your accountant cannot answer your questions or demonstrates insufficient knowledge about accounting SAF-T, this is a warning sign and may be the time to re-evaluate your partnership. A proactive and well-informed accountant is an invaluable asset to your company.

Common Errors to Avoid in Accounting SAF-T Implementation

The experience of other countries with similar systems and the challenges observed in previous versions of invoicing SAF-T allow us to anticipate some of the most common errors that companies and accounting professionals may make. Avoiding them is crucial for a successful transition.

1. Underestimating Complexity and Time Required: The implementation of accounting SAF-T is not a trivial task. It involves reviewing processes, updating software, training teams, and potentially reclassifying historical data. Underestimating this complexity and leaving everything until the last minute is a serious error that can lead to delivery failures and penalties.
2. Ignoring SNC Taxonomies: Non-compliance of the chart of accounts with SNC taxonomies is, perhaps, the most fundamental error. Many accounting software allows some flexibility in creating accounts. However, for accounting SAF-T, strict adherence to taxonomies is mandatory. A disorganised or non-standardised chart of accounts will result in validation errors and file rejection.
3. Not Testing the File in Advance: Generating a test file and validating it are critical steps. Many companies wait until the deadline to generate the file for the first time, then discovering a myriad of errors that require time and effort to correct. Testing with data from previous years allows for a proactive and gradual approach.
4. Poor Quality of Accounting Data: Accounting SAF-T is a reflection of the quality of the data that feeds it. Typographical errors, omissions, duplicate entries, or the lack of documentary support for accounting movements will be exposed. SAF-T implementation is an excellent opportunity to improve data hygiene and the quality of accounting information.
5. Lack of Communication with Software Provider: Assuming that the accounting software is "ready" without formal confirmation from the provider is a common mistake. SAF-T specifications can evolve, and it is essential to ensure that the software is updated and correctly configured to generate the file in compliance.
6. Not Involving Company Management: The implementation of accounting SAF-T is not just a technical matter or for the accounting department. It has implications for information management, internal control, and tax strategy. Lack of support and involvement from management can compromise the success of the project.
7. Not Documenting Internal Processes: The review and adaptation of accounting registration processes are fundamental. Failure to document these new processes can lead to inconsistencies and a return to old bad practices, especially with staff turnover.

Impact of Accounting SAF-T on Audit and Internal Control

In addition to direct tax implications, accounting SAF-T will have a profound impact on companies' audit and internal control processes. Its implementation represents a unique opportunity to strengthen the transparency, reliability, and efficiency of financial management.

Improved Internal and External Audit

With accounting SAF-T, auditors (internal and external) will have access to a structured and complete file of the company's accounting. This will allow for:

• More Efficient Audits: Data analysis will be faster and more comprehensive, with the possibility of using data analytics tools to identify patterns, anomalies, and potential fraud.
• Reduced Audit Costs: The automation of part of the data collection and analysis process can, in the long term, reduce the time and resources needed to carry out audits, benefiting companies with a decrease in audit fees.
• Early Identification of Risks: The ability to analyse accounting in depth will allow for the early identification of accounting and tax risks, enabling management to take corrective measures before they become major problems.

Strengthening Internal Control

Preparation for accounting SAF-T requires a review and, sometimes, a strengthening of internal control systems. This process may include:

• Standardisation of Procedures: The need to generate a consistent and accurate file encourages the standardisation of accounting registration procedures throughout the organisation.
• Segregation of Duties: The review of processes can expose weaknesses in the segregation of duties, leading to improvements that reduce the risk of errors and fraud.
• Data Quality: The requirement for high-quality data for SAF-T drives the improvement of data entry and validation processes, ensuring that accounting information is reliable from its origin.

Practical Example 2: Improving Internal Control and Efficiency

A medium-sized company has a high volume of travel and representation expenses. Before SAF-T, registration processes were manual and inconsistent, with multiple cost centres recording expenses differently. After the review for accounting SAF-T:

• Standardisation: The company implements a new expense registration procedure, with a standardised chart of accounts and cost centres, aligned with SNC taxonomies.
• Automation: A new software module allows for automatic pre-filling of expenses from electronic invoices, reducing data entry errors.
• Validation: The system implements automatic validations that prevent the registration of expenses without proper justification or outside defined budgetary limits.
• Results:
  • Error Reduction: The error rate in expense registration decreases from 15% to 2%.
  • Efficiency: The time spent on expense reconciliation and report preparation is reduced by 30%.
  • Tax Compliance: The company ensures that all expenses are correctly classified for IRC and VAT purposes, minimising the risk of tax adjustments. For example, representation expenses exceeding tax acceptance limits (CIRS, Article 23-A / CIRC, Article 23) are properly identified and treated.

This example demonstrates how preparation for accounting SAF-T can be a catalyst for improving internal processes and optimising business management.

Conclusion and Call to Action: Don't Leave the Future for Tomorrow

The postponement of accounting SAF-T until 2027 should not be interpreted as a sign that the obligation will be cancelled or that the topic can be neglected. On the contrary, it is a valuable opportunity for companies to prepare in a solid and strategic way, transforming a potential challenge into a competitive advantage.

The entry into force of accounting SAF-T in 2028 will mark a new era in the relationship between companies and the Tax Authority. The AT's ability to access detailed and structured accounting data will allow for more efficient and automated supervision, with a higher probability of detecting inconsistencies and irregularities. Companies that are not prepared will face not only the risk of fines and tax adjustments but also an administrative and reputational overload.

HVR Business Consulting has been preparing its clients for this challenge since the first ordinance, through personalised support that includes:

• Detailed diagnosis of the chart of accounts: Assessment of compliance with SNC taxonomies and identification of areas for improvement.
• Validation against taxonomies and best practices: Ensuring that not only the chart of accounts but also the registration procedures are aligned with the requirements.
• Test generation of the accounting SAF-T file: Generation and validation of test files with real data to identify and correct errors in a timely manner.
• Training and continuous monitoring: Empowering internal teams to ensure continued compliance.

Don't wait until it's too late. Proactive preparation is key to avoiding future problems and ensuring your company's tax and accounting compliance. Do you want to know if your accounting would pass the test today? Do you want to be sure that your company is ready for the future of digital taxation in Portugal?

Request HVR Business Consulting's SAF-T diagnosis — without obligation. Our team of specialists is ready to help you navigate this transition with confidence and security.

Sources and Legal References

• Ordinance No. 31/2019, of 24th January – Regulates the data structure of the accounting SAF-T (PT) file.
• Ordinance No. 302/2016, of 2nd December – Approves the taxonomies for the communication of accounting and financial data.
• Decree-Law No. 198/2012, of 24th August – Regulates the communication of invoices and other fiscally relevant documents.
• General Regime of Tax Infractions (RGIT) – Articles 114, 120, and 123.
• Corporate Income Tax Code (CIRC) – Articles 23-A and 121.
• Value Added Tax Code (CIVA) – Article 29.
• Tax Benefits Statute (EBF) – Article 35.
• State Budget for 2026 (Proposal and Final Law, when published).