E-Invoicing in Oman: Complete Guide

E-Invoicing in Oman: What Businesses Need to Know Before 2027

Oman has set binding legal dates for mandatory electronic invoicing through Decision No. 189/2026, published in Official Gazette Issue No. 1660 on 9 August 2026. The new regime relies on the 5-corner model already confirmed by the Oman Tax Authority: the invoice flows from the supplier (corner 1) to their accredited service provider (corner 2), from there to the buyer's service provider (corner 3) and on to the buyer (corner 4), while the tax data is reported in parallel to the OTA (corner 5) through the Fawtara platform. ‍

What Is an E-Invoice According to Omani Regulations?

Under Article 143 of the VAT Executive Regulations, as amended by Decision No. 189/2026, an electronic tax invoice is one issued in an approved, secure electronic format that preserves its integrity and carries a unique invoice number. The exact technical format accepted by the authorities is set out in the PINT BIS Billing Oman 1.0.1 specification, published by Peppol on 29 July 2026. In addition to the commercial invoice, the technical framework also covers the requirements for the tax data report that must be submitted to the authorities for control and reporting purposes, which is not exchanged between supplier and buyer.

Who Is in Scope?

The e-invoicing mandate applies to taxable persons registered for VAT in Oman, both established and non-established. In terms of material scope, the electronic invoicing obligation covers taxable supplies — including those made to non-taxable persons or allocated by the taxable person for their own purposes — deemed supplies, and advance payments received, whether in full or in part, prior to the supply. Article 143 also adds an open clause allowing the obligation to be extended to "any other case" determined by the Regulations.

Unlike what happens in other jurisdictions, Oman's mandate is not limited to B2B transactions: the official Fawtara FAQ confirms that B2B, B2C, and B2G transactions are all covered under the 5-corner model, and that B2C will be implemented at the same time as B2B and B2G, with no separate phase for the end consumer. That said, treatment is not identical across all cases: for B2C transactions, an invoice must be issued for each individual transaction (consolidated invoices are not permitted), and the OTA has indicated (though not yet definitively confirmed) a 24-hour submission window, compared with real-time reporting required for B2B.

The Technical Model: Oman's 5-Corner Peppol Framework

Oman has adopted the decentralised 5-corner model: the supplier (corner 1) issues the invoice through their accredited service provider (corner 2), who transmits it to the buyer's service provider (corner 3), who in turn delivers it to the buyer (corner 4); in parallel, the tax data is reported to the OTA (corner 5) via the Fawtara platform. Accredited service providers (corners 2 and 3) validate and exchange the invoices and submit the tax data to the OTA.

The technical framework is built on three Peppol specifications: PINT OM Billing (invoices and credit notes), PINT OM Self-Billing, and the Oman Tax Data Document (TDD) (tax reporting exclusively to the OTA, not commercial in nature). The invoice must be issued in XML format.

The OTA centralises technical control of the system: all accredited service providers must connect to a single SMP managed by the Authority itself, with no option to operate their own. The model also includes specific rules for particular cases: for exports, where the buyer and their service provider fall outside the Omani network, the flow is reduced to three corners (supplier, their service provider, and the OTA) without exempting the transaction from tax reporting; for imports, self-billing applies, with the buyer issuing the invoice on behalf of the foreign supplier.

Implementation Timeline

The rollout of e-invoicing in Oman follows a phased approach:

• Voluntary pilot: From August 2026 — 100 selected large VAT-registered taxpayers begin exchanging e-invoices under the Fawtara system to test the platform ahead of mandatory implementation.

• Mandatory go-live, Phase 1: 1 April 2027 — All VAT-registered taxable persons whose annual supplies exceed OMR 5 million must issue, transmit and retain tax invoices in the approved electronic format.

• Mandatory go-live, Phase 2: 1 October 2027 — All remaining VAT-registered taxable persons, whose annual supplies do not exceed OMR 5 million, come into scope.

Reporting Deadlines

Oman's legal framework distinguishes between the deadline to issue a tax invoice and the deadline to report it to the OTA once the mandate is live.

• Issuance deadline: the tax invoice must be issued within a maximum of 15 calendar days from the date of the triggering event (the supply, the deemed supply, or the receipt of an advance payment). The same 15-day deadline applies to the simplified tax invoice under Article 146(2).

• B2B reporting: according to the official Fawtara FAQ, B2B e-invoices must be submitted to the OTA in real time.

• B2C reporting: the OTA's Fawtara FAQ (June 2026 update) indicates a 24-hour submission window to the service provider for B2C transactions, rather than real time. However, the OTA's separate Service Provider FAQ, currently live on the Tax Portal, states that the B2C submission timeframe remains under discussion and that final guidance "will be announced soon." Businesses should treat the 24-hour figure as indicative rather than confirmed until the OTA publishes a definitive timeline.

One nuance worth noting: the issuance deadline (15 days) and the reporting deadline (real-time or 24 hours) apply to different stages of the same transaction — a business cannot use the 15-day issuance window to delay reporting once the invoice has actually been issued. In practice, since issuance under Fawtara takes place through an accredited service provider that validates and transmits the invoice as part of the same workflow, issuance and reporting occur very close together in time for B2B flows.

Error Correction and Invoice Cancellation

According to the official Fawtara FAQ, once a tax invoice has been issued, it cannot simply be edited or withdrawn: any adjustment must be made by issuing an electronic credit or debit note.

Technical validation takes place at the accredited service provider level — the provider is responsible for validating each invoice against Oman's schematron rules before it moves through the network. Ultimate responsibility for the invoice's compliance, however, remains with the taxable person at all times; the OTA separately monitors service provider performance and may take action if a provider fails to meet its compliance obligations.

Penalties

Neither Decision No. 189/2026 nor the wider e-invoicing framework currently sets out a specific penalty regime for non-compliance. On this point, the official Fawtara FAQ is deliberately general: "Will there be penalties for non-compliance? Penalties will apply according to regulations."

Businesses should therefore assume that non-compliance will be addressed under Oman's existing VAT penalty framework, pending further OTA guidance specific to e-invoicing.