Oman issues new corporate tax deduction rules, mandates THEQA login for tax portal

The amendments, issued under Decision No. 180 of 2026 by Tax Authority Chairman Nasser bin Khamis bin Ali Al Jashmi, clarify the regulatory requirements governing the deduction of business expenses arising from decisions issued by state administrative bodies and public entities.

Under a newly added Article 18 bis, such expenses will be deductible only if they are essential to a company’s core business activities, expressly approved by the Chairman of the Tax Authority, and do not result in a breach of any legal obligation.

The decision, which annuls any conflicting provisions and, will take effect from the tax year beginning January 1, 2027.

Separately, the authority said taxpayers and other users will be required to access its electronic portal exclusively through the THEQA digital identity application from August 1, 2026, as part of efforts to strengthen identity verification and enhance the security of its online services.

To maintain uninterrupted access, users must download the THEQA application, ensure their smartphone supports Near Field Communication (NFC) technology, register their Civil ID details and activate their digital identity.

Users will then be able to log in through the “Login via Digital Identity (THEQA App)” option and authenticate either by scanning a QR code displayed on the portal or by entering their Civil Number and approving the authentication request through the application.

The authority urged users to complete the registration and activation process before August 1, 2026, to avoid disruption to access to its electronic services.