PAN - Preliminary Assessment Notice
FAN - Final Assessment Notice
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A PAN merely informs the taxpayer of the initial findings of the Bureau of Internal Revenue. It contains the proposed assessment, and the facts, law, rules, and regulations or jurisprudence on which the proposed assessment is based. It does not contain a demand for payment but usually requires the taxpayer to reply within 15 days from receipt. Otherwise, the Commissioner of Internal Revenue will finalize an assessment and issue a FAN.
The PAN is a part of due process. It gives both the taxpayer and the Commissioner of Internal Revenue the opportunity to settle the case at the earliest possible time without the need for the issuance of a FAN.
On the other hand, a FAN contains not only a computation of tax liabilities but also a demand for payment within a prescribed period. As soon as it is served, an obligation arises on the part of the taxpayer concerned to pay the amount assessed and demanded. It also signals the time when penalties and interests begin to accrue against the taxpayer. Thus, the NIRC imposes a 25% penalty, in addition to the tax due, in case the taxpayer fails to pay the deficiency tax within the time prescribed for its payment in the notice of assessment. Likewise, an interest of 20% per annum, or such higher rate as may be prescribed by rules and regulations, is to be collected from the date prescribed for payment until the amount is fully paid. Failure to file an administrative protest within 30 days from receipt of the FAN will render the assessment final, executory, and demandable.
Commissioner of Internal Revenue v. Transitions Optical Philippines, Inc., G.R. No. 227544, November 22, 2017