If the tax exemption reason code (BT-121) is equal to VATEX-SA-EDU or VATEX-SA-HEA, then the other buyer ID (BT-46) is mandatory and must be national ID (BT-46-1 = NAT).
What does this mean?
The tax exemption reason code (BT-121) is written on the VAT breakdown of the document, and these two codes in particular are the private-education-to-a-citizen and private-healthcare-to-a-citizen entries in the VATEX list the Authority publishes. Once either appears, the other buyer ID (BT-46) becomes mandatory and the only kind accepted for it (BT-46-1) is NAT: the national ID.
The logic is visible in the rule itself: the exemption turns on a fact about the buyer rather than about the goods, so the document carries the number that establishes it. That is why an Iqama number, a passport or a commercial registration is not accepted here, even though each of them is a valid kind elsewhere.
The sharpest edge of this rule is that it names no document family. A simplified invoice normally carries no buyer identifier at all, and with either of these codes it carries one by requirement — which is exactly the case of a clinic or a school issuing to a patient or a parent at the counter. Beside it sits BR-KSA-25, a warning: a simplified document carrying either code must carry the buyer name (BT-44) as well.
The number goes in cac:PartyIdentification/cbc:ID inside the buyer party, with its kind in the schemeID attribute on that same element — not in the VAT registration field (BT-48). The general rule for a buyer who is not registered for VAT is BR-KSA-14, and this one narrows it: there you choose from a list of kinds, here there is exactly one.
Why does it happen?
Ordered from the most common to the least — your cause is most likely the first or the second.
- An establishment that set the tax treatment once at establishment level — a clinic zeroing everything — and then issued to a buyer it holds no record of at all.
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A patient holding an Iqama rather than a national ID: the number is in the file and its kind is
IQA, where the rule namesNAT. -
The number sent with no
schemeIDattribute, so the buyer looks identified while the kind is never declared. - The national ID placed in the VAT registration field instead of the party identification, which puts an invalid VAT number in the file and still leaves BT-46 empty.
- The exemption reason applied by default to every document the establishment issues, so it rides along on sales it does not cover and demands an ID that does not exist for them.
How to fix it
4 steps, then send the invoice again.
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1
Capture the national ID before issuing, not after
A Saudi national ID is ten digits beginning with 1, entered as digits with no dashes or spaces. Make it a condition in your issuing screen whenever a line carries either code, because a document that goes out without it is rejected and never recorded — there is nothing to complete afterwards except sending it again correctly.
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2
Send it in the right place with its kind
The number in
cac:PartyIdentification/cbc:IDinside the buyer party, and the kind asschemeID="NAT"on that same element. A value that does not fit the kind declared beside it opens a separate warning, BR-KSA-F-13. -
3
Check the tax treatment before you check the field
If the buyer is not a citizen, the first question is not which number to write but whether the exemption code applies to this supply at all. Who qualifies for zero-rated private education or private healthcare, and on what conditions, is a regulatory matter for zatca.gov.sa — we do not rule on it. What we can say with certainty: as long as the code is on the document, the national ID goes with it.
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4
And the note inherits the requirement
A credit or debit note correcting such an invoice carries the same exemption reason, and therefore the same identifier. The mechanics of notes are in credit and debit notes.
Once corrected, send the invoice again. A rejected invoice was never recorded with the Authority, so it needs no credit note — send the corrected invoice itself.
Does ZATCA Tools prevent it?
Yes, and at three doors rather than one. At issue the document lines are scanned: if any of them carries VATEX-SA-EDU or VATEX-SA-HEA, the customer attached to the document must hold an identifier of kind NAT in a valid shape, or the request is refused with a message in the merchant's language before anything is signed. The same check is repeated on the invoice form, on the issue path — for a draft saved before the ID was known — and in the API, where it returns the code customer_national_id_required. The check does not distinguish standard from simplified, because the rule does not.
Related codes
BR-KSA-14
Rejects the invoice
BR-KSA-25
BR-KSA-F-13
Warning
Frequently asked questions
My patient holds an Iqama, not a national ID. What do I send? +
NAT specifically, and an Iqama number is a different kind. So if the buyer is not a citizen, the issue is not the field but the tax treatment: does the exemption code apply to a supply made to a non-citizen? That is a regulatory question for zatca.gov.sa. Once the correct treatment is standard-rated, the code goes and the identifier requirement goes with it.It is a simplified document where the buyer is not normally identified. Does it still apply? +
BR-KSA-25 asks for the buyer name on the simplified document in the same situation. The difference between the two documents is in standard versus simplified tax invoices.Can I put the national ID in the VAT number field if that field is empty? +
ZATCA Tools builds the signature, the PIH, the counter and the encoding for you, and validates your data before it is sent. Completely free for now, and no credit card.
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