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Fatal — invoice rejected Invoice lines & items Shared Peppol rule PINT-AE 2026.5

How to fix ibr-088 in UAE e-invoicing

What is ibr-088?

ibr-088 is a fatal validation rule in the UAE's Peppol PINT-AE e-invoicing specification, inherited from the shared Peppol layer. It is checked against the item price and belongs to the Invoice lines & items rule group. An e-invoice that fails ibr-088 is rejected by the Accredited Service Provider gateway before it reaches the FTA.

What the official rule says

Unit code of price base quantity (ibt-150) MUST be same as invoiced quantity (ibt-130).
UAE impact: this is a fatal rule from the shared Peppol layer, enforced in the UAE profile — an invoice failing it is rejected at the Accredited Service Provider gateway before it ever reaches the FTA. A rejected invoice means resubmission delays, and late transmission risks the AED 100-per-invoice penalty under Cabinet Decision No. 106 of 2025.

Where it applies

This rule is checked against the item price of your UBL 2.1 invoice: 

cac:Price/cbc:BaseQuantity[@unitCode]

Business terms referenced

Term ID Field Other rules
IBT-150 Unit code of price base quantity view →
IBT-130 Unit code view →

Field names are derived automatically from the official rule corpus.

Technical test condition (Schematron) 
not(../../cbc:InvoicedQuantity or ../../cbc:CreditedQuantity) or (@unitCode = ../../cbc:InvoicedQuantity/@unitCode) or (@unitCode = ../../cbc:CreditedQuantity/@unitCode)

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Related rules

ibr-023 An Invoice line (ibg-25) MUST have an Invoiced quantity unit of measure code (ibt-130). ibr-cl-23 Unit code (ibt-130), (ibt-150) MUST be coded according to the UN/ECE Recommendation 20 with Rec 21 e aligned-ibrp-004 Item net price (ibt-146) MUST equal (Gross price (ibt-148) - Price discount (ibt-147)) when gross pr ibr-016 An Invoice MUST have at least one Invoice line (ibg-25) ibr-021 Each Invoice line (ibg-25) MUST have an Invoice line identifier (ibt-126). ibr-022 Each Invoice line (ibg-25) MUST have an invoiced quantity (ibt-129).. ibr-025 Each Invoice line (ibg-25) MUST contain the Item name (ibt-153). ibr-026 Each Invoice line (ibg-25) MUST contain the Item net price (ibt-146).

Rule text sourced from the official OpenPeppol PINT-AE validation artifacts (version 2026.5), refreshed weekly. Explanations are qmetrics' own guidance, not official FTA/MoF text.