Continuous supplies — ongoing contracts, retainers, leases, subscriptions, utilities — do not have a single obvious supply event. The goods or services flow without interruption. Determining when VAT becomes due on each part of that flow is one of the more technically demanding areas of Saudi VAT compliance, and one that directly affects which tax return period captures the output tax and which period allows the corresponding input tax deduction.
What Is a Continuous Supply
A continuous supply is one where goods or services are provided on an ongoing basis rather than as a single discrete event. The supply does not have a single completion date — it flows from commencement through the term of the arrangement. Common examples in Saudi business include:
- Commercial property leases and licence agreements
- Retainer-based professional services (legal, accounting, consulting)
- Maintenance and facilities management contracts
- Software licences and SaaS subscriptions
- Utilities — electricity, water, telecommunications
- Security services, cleaning contracts, and outsourced services
- Long-term construction contracts with periodic milestone or progress billing
Because continuous supplies do not resolve into a single tax point, Article 20 of the Implementing Regulations provides a specific set of rules for determining when each successive supply event occurs and when the tax becomes due.
The Three Rules for Continuous Supplies
Rule 1 — Periodic Invoicing Under Contract (Article 20(1))
Where services are supplied on a continuous basis and the contract or agreement states that consideration is payable periodically — resulting in invoices being issued on a continuous basis — the date of supply is the earliest of:
• The due date of each periodic payment
• The date payment is actually made
• The date an invoice is issued
All of the above are subject to one overriding condition: this must occur at least once in any twelve consecutive months.
A legal firm has a monthly retainer with a corporate client. The contract states that fees are due on the 1st of each month. The firm issues invoices on the 1st. The date of supply for each month’s retainer fee is the 1st — when payment falls due and when the invoice is issued simultaneously. VAT is due in the return period covering that date.
Rule 2 — Other Continuous Supplies Without Periodic Terms (Article 20(2))
For all other continuous supply cases — where the contract does not specify periodic payment terms or regular invoicing — each billing or payment event is treated as a separate supply. The tax becomes due on the earlier of the date an invoice is issued or the date payment is received, to the extent of the amount invoiced or paid.
A construction contractor issues progress invoices on a project when completion milestones are reached, but the contract does not specify fixed payment dates. Each invoice represents a separate supply event. The tax is due on the date of each invoice — or the date payment is received if earlier.
Rule 3 — The Twelve-Month Backstop (Article 20(3))
Where a continuous supply is ongoing but no invoice has been issued and no payment has been received, the supply is deemed to occur — and tax is due — on the date falling twelve months after the later of:
• The date the supply commenced, and
• The date of the previous deemed supply event (i.e., the last invoice or payment)
This is the backstop rule: it prevents VAT from being indefinitely deferred on an ongoing supply simply by not invoicing or not receiving payment. Even without any billing activity, the supply crystallises and tax becomes due after twelve months.
Long-term contracts where invoicing is irregular — particularly intercompany arrangements, management fee structures, and intragroup service agreements — frequently trigger the twelve-month backstop without the supplier or the customer noticing. If no invoice and no payment has occurred in the past twelve months for an active ongoing supply, a tax point has already passed. ZATCA auditors look specifically for these situations because they reliably produce undeclared output tax.
Special Rules: Utilities and Government Contracts
Utilities: Oil, Gas, Water, and Electricity (Article 20(4))
The supply of oil, gas, water, or electricity through a distribution network — where the supply is not made on a continuous basis — is deemed to occur on the earlier of:
- The date an invoice is issued by the supplier
- The date payment is received by the supplier
This covers metered utility billing cycles, where the supply is episodic (meter readings taken at intervals) rather than genuinely continuous.
Government Body Contracts (Article 20(5))
Where goods or services are supplied to a government body under a contract executed in accordance with the Government Tenders and Procurement Law, the date of supply and the tax due date is the earlier of:
- The date a payment order in respect of the supply is issued to the customer
- The date consideration — or part thereof — is received
This recognises the government procurement cycle and the role of the payment order as a formal billing trigger in public sector contracting.
Invoicing Implications for Continuous Supply Contracts
The date of supply rules for continuous supplies have direct consequences for invoicing discipline. Where a contract specifies periodic payment dates, the supplier should issue invoices at or around those dates — because the tax point is set by the due date, invoice date, or payment date, whichever is earliest. Delayed invoicing that occurs after the due date produces a retrospective tax point in the past, meaning the output tax should already have been declared.
| Contract Type | Tax Point Rule | Invoicing Discipline Required |
|---|---|---|
| Fixed periodic payment terms (e.g., monthly retainer) | Earlier of due date, payment, or invoice — at least every 12 months | Issue invoices on or before each due date |
| No fixed payment terms, milestone billing | Earlier of invoice date or payment receipt | Issue invoices promptly on each billing event |
| No billing, no payment for 12 months | Twelve-month backstop — supply deemed to occur automatically | Must invoice; failure to do so does not defer the tax point |
| Government contract | Earlier of payment order or receipt of consideration | Track payment order issuance as the trigger event |
- Continuous supplies — leases, retainers, maintenance contracts, subscriptions — follow specific tax point rules under Article 20, distinct from single-event supplies.
- Where the contract specifies periodic payment terms, the tax point is the earliest of: the due date, actual payment, or invoice date — and must occur at least once per twelve months.
- Where no periodic terms exist, each invoice or payment event is a separate supply, with tax due on the earlier of invoice date or payment receipt.
- The twelve-month backstop rule in Article 20(3) deems a supply to have occurred if no invoice or payment has been made in twelve months — even if no billing has taken place. Tax is due at that point regardless.
- Utility supplies (metered billing) and government body contracts follow their own specific tax point rules.
- Intragroup management fee arrangements, intercompany service agreements, and ad hoc continuous supply contracts are the highest-risk categories for twelve-month backstop failures on ZATCA audit.
- Invoicing must track contract payment terms precisely. Delayed invoicing after a contractual due date does not defer the tax point — it retrospectively places the supply in an earlier VAT return period.
This article is for informational purposes only and does not constitute legal or tax advice. Regulations referenced are based on ZATCA publications current at time of writing. Always verify with a qualified Saudi tax professional for your specific circumstances.