ZATCA Wave 24 Phase 2 E-Invoicing: 30 June 2026 Deadline

If your business recorded VAT-taxable revenue above SAR 375,000 in any of the years 2022, 2023, or 2024, your Phase 2 e-invoicing integration deadline is 30 June 2026 (3 Muharram 1448H). Miss it and you are looking at penalties under ZATCA's E-Invoicing Implementing Regulation — not warnings, actual fines. This guide cuts through the high-level summaries you have already read and gives you the exact steps, the XML traps that catch SMEs off guard, and how to apply for a penalty waiver if you have unresolved procedural issues from earlier waves.

Who Exactly Falls Under Wave 24

ZATCA assigns taxpayers to waves based on annual VAT-taxable revenue reported in VAT returns for the reference years. For Wave 24, the threshold is annual VAT-taxable revenue exceeding SAR 375,000 during calendar years 2022, 2023, or 2024. If your revenue crossed that line in any single one of those three years, you are in scope — it is not an average.

Verify your status directly on the ZATCA portal (zatca.gov.sa). Log in to your taxpayer account, navigate to the e-invoicing section, and check whether your TIN appears under Wave 24 outreach notifications. ZATCA typically sends an official notification letter 6 months before the integration deadline, so the letter should already be in your inbox or registered mail address.

Practical consequence: A holding company with multiple VAT registrations must check each registration separately. Revenue is assessed per VAT registration, not consolidated group revenue.

What Phase 2 Integration Actually Requires

Phase 1 (December 2021) was generation only — your system produced a compliant XML invoice and a QR code. Phase 2 is integration: your ERP or invoicing system must communicate in real time with ZATCA's Fatoorah platform via API.

The two transaction types have different treatment:

Invoice Type	Phase 2 Requirement	Timing
B2B Tax Invoice	Clearance — ZATCA must approve before you send to the buyer	Real-time; buyer cannot deduct input VAT on a non-cleared invoice
B2C Simplified Invoice	Reporting — upload to ZATCA within 24 hours of issuance	Near-real-time
B2B Credit/Debit Notes	Clearance (linked to original cleared invoice UUID)	Real-time

This distinction matters for your cash flow. If your ERP sends a B2B invoice to ZATCA for clearance and the call fails — wrong UUID format, missing mandatory field — the invoice is not cleared, your customer's input VAT claim is at risk, and you have an operational crisis, not just a compliance note.

The ERP Integration Checklist (Steps 1–7)

Larger firms often hand this to their IT department and consider it done. SMEs typically discover gaps at step 4. Work through this sequentially:

1. Confirm your ERP is on ZATCA's Mu'tamad-certified list — only certified solutions are permitted for Phase 2. Check the current list at zatca.gov.sa. Uncertified cloud SaaS tools used widely by SMEs are a common exposure point.

2. Register your solution in the Fatoorah portal — generate a Cryptographic Stamp Identifier (CSID) for each invoicing unit. Each physical branch or point-of-sale that issues invoices needs its own CSID under Article 7 of the E-Invoicing Implementing Regulation.

3. Configure the API endpoints — ZATCA operates separate environments: Simulation, Compliance Testing (CSTG), and Production. Do not go live on Production without passing Compliance Testing first. The CSTG requires you to submit sample invoices and receive a compliance certificate.

4. Map all mandatory XML fields — UBL 2.1 format, with ZATCA's extensions. The fields that most commonly fail in SME testing: PaymentMeans code, AllowanceCharge for discounts, TaxTotal with sub-totals per tax category, and the AdditionalDocumentReference block carrying the QR code hash.

5. Test clearance end-to-end — run 50+ B2B invoice scenarios including credit notes, zero-rated supplies, and exempt supplies. Do not limit testing to standard taxable invoices; edge cases break systems in production.

6. Train your AR and billing team — they need to understand why an invoice cannot be emailed until clearance is confirmed, and what to do when clearance is rejected (retry logic vs. manual escalation path).

7. Document your integration architecture — ZATCA auditors may request evidence of how your system handles invoice sequencing, UUID generation, and archiving under Article 53 of the E-Invoicing Implementing Regulation, which mandates 6-year electronic retention.

Common XML B2B Clearance Errors That Break SME Workflows

These are the failure modes appearing most frequently in the Compliance Testing environment, based on ZATCA's published guidance:

• Incorrect InvoiceTypeCode subtype — B2B standard invoice uses code 388, but the transaction type qualifier in the Name attribute must correctly flag whether it is a standard, simplified, or summary invoice. Mixing these causes immediate rejection.
• UUID not generated per ZATCA spec — the UUID must be a Version 4 RFC 4122 UUID generated fresh for every invoice. Sequential numeric IDs copied from legacy systems will fail.
• Hash chain broken — each invoice's PIH (Previous Invoice Hash) field must carry the SHA-256 hash of the immediately preceding invoice. A single gap invalidates the chain and can trigger a compliance investigation under Article 18 of the Implementing Regulation.
• VAT registration number format — must be exactly 15 digits starting and ending with 3. Leading-zero truncation by ERPs is a documented issue.
• Supply date vs. issue date mismatch on deferred invoices — Article 53 permits invoicing within 15 days of supply for continuous supplies, but the ActualDeliveryDate field must reflect the supply date, not the invoice date. Auditors check this on VAT reconciliation.

If you want to test your current knowledge of these technical requirements before the deadline, the SuperAccountant quiz covers ZATCA Phase 2 scenarios mapped to the current Implementing Regulation.

Penalty Waiver for Past Procedural Errors

If your business was already in scope under an earlier wave (Wave 1 through Wave 23) and has unresolved procedural violations — late reporting uploads, clearance failures not remediated, or non-certified solution use — address these before Wave 24 integration, not after.

ZATCA's penalty framework under the E-Invoicing Implementing Regulation sets fines ranging from SAR 1,000 to SAR 50,000 per violation depending on severity and recurrence. However, ZATCA has a published voluntary disclosure and penalty waiver mechanism under the VAT Implementing Regulation (Article 69 of the VAT Implementing Regulation references the general penalty framework).

To apply for a waiver on past procedural errors:

1. Log in to the ZATCA portal and navigate to Voluntary Disclosure.
2. File a corrected return or disclosure for the period in question.
3. Submit a written waiver request citing the procedural (not substantive) nature of the error — ZATCA distinguishes between errors that resulted in tax loss and those that did not.
4. Pay any outstanding VAT due in full before the waiver application is reviewed; ZATCA will not grant waivers where the underlying tax liability is unsettled.

Do not wait until after 30 June 2026 to file these. A waiver application filed before your integration go-live date strengthens your compliance posture and reduces the risk that outstanding violations trigger an audit coinciding with your Wave 24 onboarding.

Your 90-Day Action Plan to 30 June 2026

With roughly 12 weeks from the time of publication, the runway is real but not comfortable for businesses that have not started:

• Now — Week 2: Confirm wave assignment, verify ERP certification status, engage your IT vendor or ERP implementation partner in writing.
• Week 3 — Week 6: Complete CSID registration, configure API credentials, begin Compliance Testing (CSTG) environment testing.
• Week 7 — Week 10: Resolve all XML errors identified in CSTG, train billing staff, conduct User Acceptance Testing with production-equivalent data.
• Week 11 — Week 12: Switch to Production environment, parallel-run manual and system-generated invoices for one billing cycle, confirm hash chain integrity.
• 30 June 2026: Full Phase 2 integration live. Retain all CSTG compliance certificates and go-live documentation.

If your ERP vendor is quoting a timeline beyond Week 10, escalate immediately or engage a secondary certified solution provider. Integration delays are not accepted as grounds for deadline extension under current ZATCA policy.

What Auditors Will Check in the First 6 Months Post-Integration

Going live is not the finish line. ZATCA has signalled increased field audits for newly integrated taxpayers in the 6 months following their wave deadline. Expect scrutiny on:

• Input VAT claims by your customers — if a buyer claims input VAT on an invoice that was never cleared, both parties face exposure. Reconcile your cleared invoice UUIDs against your customer's VAT return data at least quarterly.
• Archiving compliance — Article 53 of the E-Invoicing Implementing Regulation requires all electronic invoices to be stored in their original XML format for 6 years. PDF copies do not satisfy this requirement.
• Continuity of the hash chain — any system migration, ERP upgrade, or data restore that breaks invoice sequence continuity is a red flag in audit. Document all system changes with timestamps.
• B2C reporting completeness — the 24-hour upload window for simplified invoices is strictly enforced. Batch uploads covering gaps of several days are treated as late submissions.

Staying compliant after go-live requires the same rigour as the integration project itself. Build a monthly compliance review into your VAT close process, not a separate annual exercise.

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