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Omani Project Director and Chartered Accountant at a Muscat construction site office reviewing blueprints, IPC certificates, and IFRS 15 cost schedules

Construction, Real Estate & EPC Contracting Accounting in Oman: IFRS 15 Percentage-of-Completion, Retentions & 5% VAT Audit Guide (2026)

Walk across the skyline of Greater Muscat today—from the flagship infrastructure corridors of Sultan Haitham City and the coastal Integrated Tourism Complexes (ITCs) of Al Mouj, Muscat Bay, and Yiti, down to the heavy industrial yards of Sohar Freezone and the Special Economic Zone at Duqm (SEZAD)—and you will see civil, mechanical, and EPC contractors operating at full capacity.

Yet behind the tower cranes and multi-million-Rial tender awards, construction and real estate enterprises face the most complex accounting, tax, and statutory audit rules in the Sultanate of Oman. Unlike a trading or retail business where a sale happens at a checkout counter, an Omani contracting company spans multi-year engineering schedules, 10% performance retentions locked up for 12 to 24 months after Practical Completion, advance payment bank guarantees, unapproved variation orders (VOs), Liquidated Damages (LDs), and strict Oman Tax Authority (OTA) scrutiny over when 5% VAT and 15% Corporate Income Tax actually fall due.

At Muscat Auditing & Accounting Services, our Audit & Assurance Practice in Oman audits dozens of Grade-1, Excellent-Grade, and international EPC contractors every year. We repeatedly see profitable engineering companies hit severe working-capital crunches—or receive hefty OTA tax assessments—simply because their project accountants booked revenue based on cash received or raw Interim Payment Certificates (IPCs) rather than IFRS 15 Percentage-of-Completion (POC) rules.

Here is the definitive 2026 field guide for Omani construction executives, real estate developers, quantity surveyors, and project CFOs on structuring audit-proof contracting accounts in Oman.

1. IFRS 15 Revenue Recognition for Omani Contractors: Input Method (Cost-to-Cost) vs. Output Method (Certified IPCs)

When preparing annual financial statements for submission to commercial banks (such as Bank Muscat, National Bank of Oman, or Sohar International for project bonding facilities), the Ministry of Commerce, Industry and Investment Promotion (MOCIIP), and the Oman Tax Authority (OTA), Omani contractors must comply strictly with *IFRS 15 (Revenue from Contracts with Customers)*.

Under IFRS 15, construction and EPC contracts almost always satisfy the criteria for revenue recognition over time (because the contractor’s work creates or enhances an asset that the client controls as the site is built, or creates an asset with no alternative use where the contractor has an enforceable right to payment for performance completed to date).

However, how you measure that progress at 31 December determines whether your balance sheet passes a statutory audit:

A. Why Booking Revenue Strictly by Approved IPCs (Output Method) Often Fails an Audit

Many contractors in Ruwi and Ghala simply sum up the Engineer-Certified Interim Payment Certificates (IPCs) issued up to 31 December and call that “Annual Revenue.”

B. The Gold-Standard Input Method (Cost-to-Cost Stage of Completion)

Both external auditors and the Oman Tax Authority strongly favor the Input Method (Cost-to-Cost Percentage of Completion), provided your Accounting & Bookkeeping Systems maintain a disciplined job-costing ledger per project:

Stage of Completion (%)) = (Cumulative Actual Contract Costs Incurred to Date)) ÷ (Total Estimated Contract Costs (Actual to Date + Cost to Complete)))

Worked OMR Example for a Muscat Infrastructure Contract:

Suppose your LLC wins a OMR 5,000,000 civil contracting package in Barka with a total budgeted cost of OMR 4,000,000 (estimated gross profit = OMR 1,000,000 or 20%).

Crucial Audit Trap — Uninstalled Site Materials: Under IFRS 15, if you deliver OMR 300,000 of elevator shafts or chillers to the construction site on 28 December that are sitting in crates uninstalled, you cannot include that OMR 300,000 in the numerator of your Cost-to-Cost percentage calculation! Uninstalled materials must be parked in Project Inventory / Materials on Site until physically integrated into the works, or recognized at zero margin up to cost.

Audit manager and Omani project quantity surveyor in Ghala Muscat comparing engineering BOQ progress sheets with IFRS 15 accounting schedules
Figure 1: Audit manager and Omani Quantity Surveyor in Ghala reconciling engineering Bill of Quantities (BOQ) progress against IFRS 15 cost-to-cost revenue schedules.

2. Oman 5% VAT Tax Point Rules for Construction: Advance Payments, IPCs & 10% Retention Money

Nothing creates more confusion between project engineers and tax accountants than the Time of Supply (Tax Point) rules for continuous supplies of construction services under the Oman VAT Law (Royal Decree 121/2020) and the Oman Tax Authority’s Real Estate & Construction Sector VAT Guide.

In standard Omani FIDIC-style construction contracts, three cash streams happen on completely different timelines:

  1. 10%–20% Advance Mobilization Payment (paid before work starts, amortized across future IPCs);
  2. Monthly Interim Payment Certificates (IPCs) (certified by the consultant, invoiced, and paid 30–60 days later); and
  3. 10% Retention Money (5% released at Taking-Over Certificate / Practical Completion, and 5% released 12 months later after the Defects Liability Period DLP expires).

Here is how our Taxation Services Team in Muscat configures ERP invoicing for construction clients so they neither overpay VAT prematurely nor incur OTA late-payment penalties:

Contract Event / Cash Stream When Is 5% Oman VAT Triggered (Tax Point)? How to Issue the Tax Invoice & Book the Ledger
1. Advance Mobilization Payment (e.g., 10% = OMR 500,000) On the date the advance cash is received (or when a tax invoice is issued for the advance, whichever is earlier). Issue a VAT Tax Invoice for the advance receipt (OMR 500,000 + 5% VAT = OMR 25,000). On each subsequent monthly IPC, deduct the pro-rata advance recovery before calculating 5% VAT so you never pay VAT twice on the same OMR 500,000!
2. Monthly Certified IPC (Continuous Supply of Construction) The earliest of: (a) Date of issuing the Tax Invoice, (b) Date of receiving payment, or (c) Due date of payment specified in the contract/IPC (and no later than 12 months from start/previous invoice). Pro-Tip: Do NOT issue a formal “Tax Invoice” when submitting an uncertified draft valuation to the consultant! Submit a “Draft Payment Application / Pro-Forma Valuation.” Issue the official sequential Fawtara-compliant Tax Invoice only once the consultant signs the IPC!
3. 10% Contract Retention Money (Withheld for DLP) Under OTA construction VAT rules, if retention is not yet due and payable until the Taking-Over Certificate (TOC) or Defects Liability Certificate (DLC) is issued, VAT on the retained 10% portion is deferred until the retention becomes due for invoicing/payment (unless you invoice 100% gross on the Tax Invoice upfront!). Structure your Tax Invoice face calculation carefully: invoice the net payable certified value (after advance amortization and retention deduction) for VAT purposes, and issue a dedicated Retention Tax Invoice when the 5% TOC and 5% DLC milestones fall due.
Omani CFO and real estate developer finance team in Muscat reviewing subcontractor interim payment certificates and retention money VAT ledgers
Figure 2: Real estate and contracting finance executives in Muscat reviewing subcontractor Interim Payment Certificates (IPCs), 10% retention ledgers, and bank guarantee schedules.

3. Accounting for Variation Orders (VOs), Claims, and Onerous Loss-Making Contracts (IAS 37)

In the real world of Omani contracting, site conditions change. Rock excavation in Bousher takes longer than expected, a client instructs additional MEP fit-outs, or global steel and copper prices surge mid-contract.

A. Unapproved Variation Orders (Variable Consideration Under IFRS 15)

Can you book revenue at 31 December for a OMR 350,000 Variation Order that your project manager submitted to the client, if the client has not yet signed the variation instruction?

B. Loss-Making (Onerous) Contracts Under IAS 37

Suppose you bid aggressively on a OMR 2,000,000 road subcontract, and six months in, revised engineering estimates show total costs to complete the job will reach OMR 2,300,000 (an expected total contract loss of OMR 300,000).

4. Plant, Heavy Machinery & Site Fixed Asset Verification in Sohar, Duqm & Muscat (IAS 16 & IAS 36)

For civil, oilfield, and marine EPC contractors operating fleets of excavators, mobile cranes, batching plants, and generators across remote project sites in Duqm, Fahud, Qarn Alam, and Sohar, the Fixed Asset Register (FAR) is a primary audit focus area:

  1. Component Accounting & Overhaul Capitalization (IAS 16): Major engine overhauls and crane boom replacements that extend economic life must be capitalized and depreciated separately over the overhaul cycle, while routine site maintenance and tires/filters are expensed immediately.
  2. Physical Site Verification & Idle Plant Impairment (IAS 36): When a major pipeline or infrastructure contract finishes and specialized machinery sits idle in an equipment yard, our Inventory & Fixed Asset Physical Verification Audit Team conducts barcode-tagged site inspections and IAS 36 recoverable-amount impairment tests.
  3. ICV Depreciation Bonus for PDO, EDO & OQ Contractors: Under Oman’s In-Country Value (ICV) certification formula for the energy and oilfield sector, depreciation of Omani-owned heavy plant and equipment—alongside procurement from local Omani manufacturers and Omanization payroll—directly increases your ICV Score on major tenders!
Physical asset verification auditors in safety vests and hard hats inspecting heavy earthmoving equipment and steel inventory at a Duqm Oman EPC yard
Figure 3: On-site physical verification of heavy earthmoving plant, batching machinery, and structural steel inventory by Muscat Audit specialists in Duqm.

5. Real Estate Developers & Integrated Tourism Complexes (ITCs): Off-Plan Escrow Audits & VAT Exemptions

If your business develops residential villas, commercial towers, or off-plan hospitality units inside an Integrated Tourism Complex (ITC) or freehold development zone in Oman (which also qualifies buyers for the Oman Golden Residency / Investor Visa), you must navigate three specialized regulatory requirements:

  1. Off-Plan Project Escrow Account Audits (Ministry of Housing & Urban Planning): Under Omani real estate development regulations, developers selling off-plan units must maintain dedicated Project Escrow Accounts with an approved Omani commercial bank. Releases of buyer milestone funds from the escrow account require independent certification by a licensed audit firm verifying that construction progress on the ground matches the stage payments requested.
  2. Mixed-Supply VAT Apportionment (Commercial vs. Residential Real Estate):
  3. Commercial Real Estate Sales & Leases: Standard-rated at 5% VAT (full Input VAT recovery on construction costs).
  4. First Supply of New Residential Properties / Bare Land vs. Subsequent Residential Leases: Under Oman VAT Executive Regulations, the resale and long-term lease of residential properties are generally VAT-Exempt, meaning developers constructing mixed-use buildings (e.g., ground-floor retail shops + 6 floors of residential apartments in Al Khuwair) must apply a rigorous Input VAT Partial Exemption Apportionment Formula so they do not unlawfully claim Input VAT attributable to exempt residential leases!
  5. ERP Job-Costing Architecture: Implementing project-centric ERP modules via our Accounting Software & ERP Implementation Services in Oman allows real estate developers to track land bank cost, infrastructure allocation, escrow inflows, and unit handover margins down to the individual villa or apartment plot.
Omani financial audit advisor and real estate developer executive reviewing architectural scale models and project escrow audit reports in Muscat
Figure 4: Reviewing off-plan project escrow account audit certifications and milestone drawdowns inside a luxury Integrated Tourism Complex (ITC) development office in Muscat.

6. Related Omani Compliance & Audit Guides

Strengthen your financial governance across all departments with our 2026 technical guides:

7. Frequently Asked Questions (FAQs): Construction, Real Estate & EPC Accounting in Oman

1. When is 5% Oman VAT payable on 10% construction retention money?

Under the Oman Tax Authority’s Real Estate & Construction VAT guidelines, if 10% retention money is withheld by the client until the issuance of the Taking-Over Certificate (TOC) or Defects Liability Certificate (DLC)—and is not invoiced as currently due on the interim tax invoice—the VAT tax point for the retention portion is deferred until the retention milestone becomes due for payment or a retention tax invoice is issued, whichever occurs first.

2. Why shouldn’t an Omani contractor issue a formal VAT Tax Invoice when submitting an uncertified draft IPC to the consultant?

Under Article 26 of the Oman VAT Law, issuing an official Tax Invoice immediately triggers the 5% Output VAT liability in that tax quarter—even if the client’s quantity surveyor takes 60 days to certify the valuation or reduces the claimed amount! Contractors should submit a “Payment Application / Draft Valuation Certificate” for consultant certification first, and issue the official Fawtara-compliant Tax Invoice only upon formal IPC certification.

3. How does the Oman Tax Authority audit IFRS 15 Percentage-of-Completion (POC) revenue in construction companies?

During a corporate tax inspection, the OTA compares each project’s contract value, cumulative certified IPCs, job-costing ledger (actual material, labor, and subcontract costs incurred), and estimated cost-to-complete. If a contractor shifts costs between profitable and loss-making projects or includes uninstalled site materials in the cost-to-cost progress percentage to manipulate year-end taxable profit, the OTA recalculates project taxable income under Article 60 of the Income Tax Law.

4. Do foreign subcontractors working on EPC projects in Oman trigger 10% Withholding Tax (WHT)?

Yes. If an Omani main contractor pays a foreign engineering, design, or technical consultancy firm (that does not have a registered Oman branch / Permanent Establishment and Oman Tax Card) for engineering design, supervision, or technical services, the Omani contractor must deduct and remit 10% Withholding Tax (WHT) to the Oman Tax Authority by the 14th of the following month.

5. What is a Project Escrow Audit for off-plan real estate developers in Oman?

Real estate developers constructing off-plan residential or ITC properties in Oman are required to deposit buyer installment payments into a ring-fenced Project Escrow Account. Before the bank releases stage funds to the developer, an accredited external audit firm and project engineer must audit and certify that funds are used exclusively for construction of that specific project in alignment with verified physical build milestones.

Partner with Oman’s Construction, EPC & Real Estate Audit Specialists

From IFRS 15 Percentage-of-Completion project audits and bank facility covenants to ICV energy tender certifications and off-plan escrow assurance, Muscat Auditing & Accounting Services safeguards the financial integrity of Oman’s leading contractors and developers.

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