Argentina’s tax authority has launched an online service for preparing and filing corporate income tax returns for fiscal years ending in June 2026 or later. Use will become mandatory from 1 March 2027, replacing the SIAP application for eligible returns.
Argentina’s tax authority (ARCA) announced on 19 October 2026 that it has launched the Corporate Income Tax Web service, an online platform for preparing and filing annual corporate income tax returns.
Companies with fiscal years ending in June 2026 or later must prepare their returns through it.
Until 28 February 2027, filers may use the service on an optional basis.
Trial period and timeline
The trial period ends on 1 March 2027. From that date, use of the web service will become mandatory.
General Resolution 5908/2026 sets out the gradual replacement of the SIAP application, and the measure aims to modernise and simplify services for taxpayers and those responsible for tax obligations.
SIAP remains in use for original and amended returns covering fiscal years that ended before June 2026. For fiscal years ending in June 2026 or later, amended returns must follow the same channel used for the original return, whether that is SIAP or the web service.
The service applies to the entities listed in sections a, b, c, and d of Article 53, and in its last paragraph, of the Income Tax Law, when they prepare financial statements.
Key changes for filers
Financial statements are now shorter. The system no longer asks for detailed breakdowns of each item or for the Tax Identification Number (CUIT) of major debtors and clients. Assets appear on a single screen, grouped into cash and banks, investments, loans, fixed assets, inventory, and intangible assets, with each category split into current and noncurrent items.
Withholdings, collections, advance payments, and payments on account arrive already loaded from ARCA’s records. Filers have less manual entry to do, and the risk of mismatches between what they declare and what the agency records drops.
Losses and credits carry over automatically from earlier returns. The exception is the first year of use, when filers must enter the carryover data by hand.
Net results and tax adjustments now sit on one screen. The net result is calculated by type of activity and combines income from Argentine and foreign sources. Positive and negative adjustments are entered together in a single view.
