The article drafted by Mladenovic Paripovic, Senior Associate & Jelena Pejovic, Associate on 20 May, 2026
Over the past several years, Serbia has gradually transformed its tax compliance framework through the implementation of mandatory electronic invoicing and increased digital supervision by the tax authorities. What initially appeared to be a technical modernization initiative has, in practice, evolved into a much broader compliance ecosystem affecting accounting, finance, legal, and operational risk management within companies.
The latest amendments applicable from April 2026 continue this trend by introducing additional obligations concerning internal invoicing through the Serbian Electronic Invoicing System (“SEF”). Although internal invoices have long existed under Serbian VAT regulations, the new rules significantly change their practical role and compliance importance. Transactions and VAT adjustments that previously remained largely within internal accounting records are now becoming part of a centralized electronic reporting structure directly accessible to the Serbian tax authorities.
It is noted that the obligation applies to business entities in B2B transactions (between businesses) and B2G transactions (between businesses and public sector entities), whereas in B2C transactions, (business to consumer) the obligation of universal mandatory electronic invoicing has not yet been introduced. In essence, internal VAT adjustments are no longer intended to remain exclusively within internal accounting records. Instead, they are becoming part of a centralized electronic reporting structure directly visible to the authorities. For many companies, this represents a shift from traditional bookkeeping practice toward a far more transparent and controlled compliance environment.
From Internal Accounting Documentation to Regulatory Reporting Instrument
Historically, internal invoices in Serbia were often treated as supporting accounting documentation prepared primarily for VAT calculation purposes. In practice, many businesses handled such documents manually, often without standardized workflows or dedicated internal control procedures.
By requiring certain internal invoices and VAT adjustment mechanisms to be processed through SEF, the legislator has effectively transformed internal invoicing into a formal regulatory instrument. This is particularly relevant in situations involving reverse-charge VAT obligations, corrections of the taxable base, VAT adjustments following invoice cancellations or amendments, advance payments and subsequent reconciliations, as well as corrective documentation linked to previously reported VAT transactions. The practical consequence is straightforward: transactions that previously remained largely within the internal accounting sphere are now entering a system of centralized electronic supervision maintained by the tax authorities.
Increased Transparency and Expanded Audit Visibility
At first glance, the amendments may appear administrative or technical in nature. However, their broader significance lies in the enhanced transactional visibility they provide to the Serbian tax authorities.
Through SEF, the authorities already possess extensive insight into outgoing and incoming invoices. The inclusion of internal invoices further expands this visibility by enabling regulators to monitor correction histories, VAT adjustments, timing of corrections, relationship between original and corrective invoices, internal tax calculations and reconciliation consistency between accounting and VAT recording significantly greater detail, thereby creating a fundamentally different audit environment.
As a result, accounting inconsistencies are more easily identifiable during audits. For example, where a company issues a corrective invoice but delays the corresponding VAT adjustment through SEF, discrepancies between VAT returns, accounting ledgers, and electronic invoice records may be automatically detected through cross-checking mechanisms.
As Serbian tax supervision becomes increasingly data-driven, compliance exposure is no longer limited to incorrect VAT outcomes alone. The integrity, timing, and consistency of the underlying process have become equally important.
You can read the full article here: Mandatory Internal Invoicing Through SEF – A New Compliance Reality for Serbian Companies in 2026