You're issuing an invoice to a vendor whose NPWP doesn't validate against the tax database. Your accounting software flags it. Your finance team asks: do we really need to fix this before we send it? The answer isn't what you think it is. Indonesia's tax rules have split into two lanes—one for invoices and one for e-Faktur. They're not the same. Most businesses treat NPWP validation as a hard gate on every invoice, but the actual requirement is narrower and more forgiving than that. Get it wrong and you either block legitimate work or sail into an audit. Get it right and you move faster without losing compliance. What NPWP validation actually does (and doesn't do) NPWP stands for Nomor Pokok Wajib Pajak—a tax ID issued by the Directorate General of Taxes (DGT). When you validate it, you're checking that the number exists, hasn't been suspended, and matches a registered business name. What validation does not check: Whether the vendor is current on tax payments Whether they've filed returns on time Whether they're authorized to issue invoices themselves Whether the address on file is still accurate Validation is a hygiene check, not a solvency check. It catches typos, inactive accounts, and abandoned registrations. It does not tell you whether you should trust the vendor. This matters because many teams assume that a passed NPWP validation means the invoice is safe to issue. It isn't. It just means the number is real and currently active. B2B invoices: NPWP matching is recommended, not mandated Under Indonesia's general invoicing law (UU No. 8 Tahun 1997), B2B invoices must contain certain fields: invoice number, date, description of goods/services, quantity, price, and tax amount. NPWP of the buyer is on that list—but not with a validation requirement attached. The tax office expects you to collect the buyer's NPWP. They do not require you to match it against a live registry before issuing the invoice. This is the gap where most confusion lives. In practice: If the NPWP is missing, the invoice is incomplete and may be challenged in an audit. If the NPWP is present but wrong, the invoice itself is not invalid—but the tax office may disallow the input tax credit on the buyer's end, which makes them unhappy and can trigger a request for correction. If the NPWP doesn't validate, you can still issue the invoice. You just can't claim it as proof of a legitimate business transaction if audited. The rule is: collect the NPWP, keep it on file, and be ready to defend it. Validation is a guardrail, not a gate. E-Faktur: where validation actually becomes mandatory E-Faktur is different. This is the electronic invoicing system that Indonesia's tax office runs. If you're registered as a Pengusaha Kena Pajak (PKP—a VAT-registered business), and you issue invoices with VAT, those invoices must be submitted to e-Faktur. E-Faktur does validate NPWP on submission. The system checks: The buyer's NPWP exists and is active The buyer is a registered PKP (if they should be) The format matches tax office rules If validation fails, the system rejects the invoice and you cannot submit it to the tax office. This is a hard stop. The timeline matters here. If you issue an invoice on paper or PDF before submitting to e-Faktur, NPWP validation is a courtesy. Once you submit to e-Faktur, it becomes a requirement. Key point: You can issue a B2B invoice with an unvalidated NPWP. You cannot submit that same invoice to e-Faktur if the NPWP doesn't validate. The validation gate moves, depending on where the invoice is in its lifecycle. When a vendor's NPWP doesn't validate: the three paths forward You've issued an invoice and the NPWP bounces. Here's what actually happens: Path 1: The vendor is not yet registered (most common) A new contractor or small supplier hasn't registered for NPWP yet. They give you a number, but it doesn't exist in the system. You have three options: Wait. Ask the vendor when they expect to register and hold the invoice. This is safe but slow. Issue without validation, collect the corrected NPWP later. Include a note in your records that you attempted validation and will update when the number is live. This is common and auditable if you document it. Issue to a personal NPWP if the vendor is a sole proprietor. Some invoices can be issued to an individual's NPWP rather than a business NPWP. This is legitimate if the contract is structured that way. Do not block the invoice. Do document why. Path 2: The NPWP exists but is suspended or deactivated The vendor's NPWP was once valid and now isn't. This is rarer, but it happens. The vendor may owe back taxes, missed filing deadlines, or simply let the registration lapse. In this case, do not issue the invoice until the vendor provides proof of reinstatement or a new, active NPWP. This is a material change in vendor status and affects your tax position. Path 3: The NPWP format is wrong Typos in NPWP numbers are common. An extra digit, a transposed number, a different digit enti