The legal timetable

Oman Tax Authority Decision No. 189/2026, issued 3 August and published in Official Gazette issue 1660, provides mandatory commencement from 1 April 2027 for taxable persons whose annual supplies exceed OMR 5 million. Those whose annual supplies do not exceed OMR 5 million follow from 1 October 2027.

The instrument amends VAT invoicing provisions, including approved electronic format, unique invoice identification and system safeguards. The reviewed source is a reproduction of the Arabic Gazette instrument, not an English OTA announcement.

Separate the pilot from mandatory application

The OTA Fawtara FAQ still describes an August 2026 first cohort of 100 large VAT registrants and subsequent phased programme dates. That programme account should not be used to override the mandatory commencement dates in the enacted decision.

This correction does not establish that the pilot was cancelled. Businesses participating in a pilot should follow their direct onboarding instructions while identifying the statutory date that applies to them.

A threshold needs the correct measure

T&M analysis: the decision uses annual supplies. Businesses should avoid substituting an unrelated revenue figure or assuming that a programme label such as large taxpayer answers the threshold question.

Document the calculation and review uncertain supply classifications. Then align invoicing, credit-note handling, access controls, record retention and recovery arrangements with the legal and technical requirements.