What the decision changes

Oman’s Tax Authority has issued Decision No. 189/2026, amending the Executive Regulations of the VAT Law (Royal Decree No. 121/2020). It sets out how tax invoices must be generated, secured, retained and exchanged electronically, and makes electronic tax invoicing mandatory in two phases from April 2027.

Under the amended Article 143, a VAT-registered business must issue tax invoices in an approved and secure electronic format, with measures that keep each invoice intact and retained, and every electronic invoice must carry a unique number. Each tax invoice must be issued within 15 days of the supply. The requirement covers supplies to other businesses and to people who are not registered for VAT — in a shop, that is your walk-in customer. It also covers deemed supplies and payments received before the date of supply.

The receipt from your till: same deadlines, details pending

Most shop sales end with a simplified tax invoice — the short receipt the till prints for a customer. The decision rewrites Article 146 so that simplified tax invoices must be issued within the same timeframes set in Article 143. What it does not yet spell out are all the technical details for these consumer (B2C) invoices — those are for the Tax Authority to set, and some are still pending.

In practice, plan as if the rules reach the counter, not just the accounts office. A cash register that only prints paper, or invoices typed in Word or Excel, will not produce invoices in an approved electronic format on its own. If you sell from more than one till or branch, have every one of them issue invoices from the same system — and watch for the Tax Authority’s specifications for simplified invoices.

Licensed providers: what to ask your POS vendor

Under the new Article 143 bis, the Tax Authority will notify businesses of the companies licensed to provide tax invoicing services in an approved electronic format, and businesses must use those recognised providers. Your POS or accounting system therefore needs to work with one of them. Before your date, ask your vendor:

  • Which Tax Authority-licensed provider will your system connect to?
  • Will the connection be live and tested before my phase starts?
  • Does it cover simplified invoices from every till and every branch?
  • What happens to sales if the internet or the connection drops?
  • What will it cost per branch or per till, and when will I know?

Breakdowns, backups and security

Article 143 bis 1 adds obligations that matter at a busy counter. Electronic tax invoices must be issued securely through an electronic system that meets the Tax Authority’s technical specifications. The system must be protected against breaches and unauthorised access, and you need procedures for emergencies, system breakdowns and technical malfunctions, plus a way to recover data if it is lost.

For a shop, that means a login for every member of staff rather than one shared password, regular backups, and a written plan for a power cut or an internet outage at the till. Check the Tax Authority’s technical specifications for the details that apply to you.

Which date is yours, and how to work back from it

The first phase starts on 1 April 2027 for businesses with annual supplies above OMR 5 million. The second starts on 1 October 2027 for every other VAT-registered business, which includes almost every independent shop and small chain. If you are not registered for VAT, the decision does not set a date for you.

Work backwards from your date: get every sale into one POS now, clean up your product list and its VAT treatment, confirm your vendor’s provider connection and test it, then train cashiers in the weeks before you go live. Leave a margin — the last month before a deadline is when every vendor is busiest.

Where CloudTech POS fits

CloudTech POS issues VAT invoices and receipts from every till and branch today, in Arabic and English. We are developing an e-invoicing connector that will work through a Tax Authority-licensed provider. Its timeline for your shop — and the onboarding plan, including importing your product list — is confirmed after a technical assessment.

For the full timeline and a six-step checklist, read our e-invoicing readiness guide. Running a hotel or guesthouse? Read e-invoicing for hotels and guesthouses.

Sources: Tax Authority Decision No. 189/2026 (Official Gazette No. 1660, 3 August 2026 — PDF in Arabic); Oman Observer — “Oman sets phased mandatory e-invoicing regime”. Last reviewed . This article is a plain-language summary, not tax advice; check the technical specifications on the Tax Authority portal.