Final Assessment Notice (FAN)
Updated June 13, 2026
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Definition
A Final Assessment Notice (FAN) is the BIR's formal assessment of deficiency tax, surcharge and interest, issued with a Formal Letter of Demand; it becomes final, executory and demandable if not protested within 30 days of receipt.
The Final Assessment Notice states the BIR's determination of a taxpayer's deficiency after an examination or investigation. It is issued together with a Formal Letter of Demand (FLD) and normally follows a Preliminary Assessment Notice (PAN), which the taxpayer may answer within 15 days. A PAN is not required in the cases listed in Section 228, such as mathematical errors on the face of the return or a discrepancy between tax withheld and tax remitted by a withholding agent. The FAN is issued under Section 228 of the National Internal Revenue Code (NIRC). The taxpayer must be informed in writing of the law and the facts on which the assessment is based; otherwise the assessment is void. The procedure is detailed in Revenue Regulations No. 12-99, as amended by RR 18-2013. Upon receipt, the taxpayer has 30 days to file a protest, either a request for reconsideration or a request for reinvestigation. For a reinvestigation, all supporting documents must be submitted within 60 days from filing the protest. If no protest is filed in time, the assessment becomes final, executory and demandable, and the BIR may collect through distraint, levy or court action.
Detailed explanation
What is a Final Assessment Notice?
A Final Assessment Notice (FAN) is the BIR's official written assessment telling a taxpayer that a tax deficiency has been found, together with the surcharge and interest. It is issued with a Formal Letter of Demand (FLD) at the end of an audit or investigation (NIRC §228; RR 12-99, as amended by RR 18-2013). The FAN starts the 30-day period for filing a protest.
Legal Basis and Authority
The assessment process is governed by NIRC §228. The detailed procedure is in Revenue Regulations No. 12-99, as amended by RR 18-2013. The taxpayer must be informed in writing of the law and the facts on which the assessment is made; otherwise, the assessment is void (NIRC §228).
Components of a FAN
A FAN typically includes: (1) the taxpayer's identification details; (2) the tax type and period under assessment; (3) the breakdown of the deficiency (basic tax, surcharge, and interest); (4) the factual and legal basis for the assessment; (5) the amount due and the date by which it must be paid; and (6) the date of issuance. Any compromise penalty is shown in a separate notice, not in the FAN (RMO 7-2015).
When a FAN is Issued
A FAN is issued after the BIR has completed its examination and determined that a deficiency exists. It usually follows: (1) a Preliminary Assessment Notice (PAN) stating the findings; (2) the taxpayer's reply to the PAN within 15 days, or the lapse of that period; and (3) the BIR's review of that reply. A PAN is not required in the cases listed in NIRC §228, such as mathematical errors on the face of the return, a discrepancy between tax withheld and tax remitted, or unpaid excise tax on excisable articles.
Taxpayer Rights Upon Receipt of FAN
Upon receipt of a FAN, a taxpayer may: (1) file a request for reconsideration or reinvestigation within 30 days from receipt (NIRC §228); (2) for a reinvestigation, submit all supporting documents within 60 days from filing the protest; (3) appeal to the Court of Tax Appeals (CTA) within 30 days from receipt of a denial, or from the lapse of 180 days from submission of documents without a decision; and (4) pay the assessment and claim a refund within two years from payment (NIRC §229). If no protest is filed within 30 days, the assessment becomes final, executory and demandable.
Penalties and Interest in a FAN
A FAN includes not only the unpaid tax but also: (1) a 25% surcharge on the unpaid tax (NIRC §248(A)); (2) a 50% surcharge instead, for willful neglect to file or a false or fraudulent return (NIRC §248(B)); and (3) interest at 12% per annum from the due date of the tax until full payment (NIRC §249). Micro and small taxpayers pay a 10% surcharge and 6% interest instead (RA 11976).
Finality and Collection
If a taxpayer does not protest within 30 days of receiving the FAN, or does not submit supporting documents within 60 days for a reinvestigation, the assessment becomes final. The BIR may then collect through: (1) distraint of personal property, including garnishment of bank deposits; (2) levy on real property; and (3) civil or criminal court action (NIRC §205 to §207). Courts cannot enjoin collection (NIRC §218), although the CTA may suspend collection during an appeal if the taxpayer deposits the amount or files a surety bond (RA 1125, Sec. 11, as amended).
Distinction from Other Assessment Notices
Do not confuse a FAN with other BIR notices: (1) a Preliminary Assessment Notice (PAN) states the BIR's initial findings and gives the taxpayer 15 days to reply; (2) the Formal Letter of Demand (FLD) is the demand for payment issued together with the FAN; and (3) a Final Decision on Disputed Assessment (FDDA) is the BIR's decision on a protest, which can be appealed to the CTA. The FAN is the formal assessment that can be protested (RR 12-99, as amended by RR 18-2013).
Why it matters
A FAN formally establishes your tax liability and starts a strict 30-day protest period. Missing it makes the assessment final, and the BIR may then collect by distraint of personal property, including bank deposits, or levy on real property. Understanding the FAN's contents and your protest rights can mean the difference between resolving a dispute administratively or facing collection enforcement.
How it works
Receipt and Review
Upon receiving a FAN, carefully verify the taxpayer identification, tax period, and computation of the deficiency. Check that it states the law and the facts on which the assessment is based, as NIRC §228 requires. Preserve the original FAN and proof of the date of receipt, since the 30-day period runs from receipt.
Determine Appeal Strategy
Within 30 days of receipt, decide whether to protest or pay. A protest may be a request for reconsideration (a review on the existing records) or a request for reinvestigation (a review on newly submitted evidence) (NIRC §228; RR 12-99, as amended by RR 18-2013). If you agree with the assessment, pay it to stop further interest.
File Appeal or Pay
If protesting, file the written protest with the office that issued the FAN within the 30-day window, explaining why the assessment is wrong. For a reinvestigation, submit all supporting documents within 60 days from filing the protest, or the assessment becomes final. If paying, remit the full amount due.
Monitor Appeal Status
If the protest is denied, or not acted upon within 180 days from submission of documents, you may appeal to the Court of Tax Appeals (CTA) within 30 days from receipt of the decision or from the lapse of the 180-day period (NIRC §228).
Examples
Salaried employee with unreported rental income
Juan dela Cruz, an employee with ₱800,000 taxable compensation, failed to report ₱200,000 in annual rental income. Using the 40% optional standard deduction, his net rental income is ₱120,000, taxed at his 25% bracket: ₱30,000. The FAN adds a ₱7,500 surcharge (25%) and ₱3,600 interest (12% for one year). Juan has 30 days to protest or pay ₱41,100 total (NIRC §228, §248, §249).
Self-employed professional with overstated deductions
Maria Santos, a freelance consultant with ₱1,200,000 gross receipts, claimed ₱600,000 in business expenses without supporting receipts. The BIR disallowed ₱300,000, raising her taxable income from ₱600,000 to ₱900,000 and her tax from ₱62,500 to ₱127,500, a ₱65,000 deficiency. As a micro taxpayer she pays a 10% surcharge (₱6,500) and 6% interest (₱3,900 for one year) instead of 25% and 12% (RA 11976), for ₱75,400 total.
Corporation with underreported sales
ABC Trading Corp., a small corporation taxed at 20%, reported ₱5,000,000 in sales but the BIR audit found ₱6,500,000. Treating the ₱1,500,000 of undeclared sales as taxable income, the income tax deficiency is ₱300,000. As a small taxpayer it pays a 10% surcharge (₱30,000) and 6% interest (₱18,000 for one year), for ₱348,000 in income tax items alone. It must protest or pay within 30 days (NIRC §27(A), §228; RA 11976).
OFW assessed on income earned abroad
Anna Reyes, a Filipino working in Dubai, receives a FAN that taxes ₱800,000 of her Dubai salary. As an overseas Filipino worker, a nonresident citizen, she is taxed only on income from Philippine sources (NIRC §23(B), (C)), so she files a protest within 30 days with her employment contract and proof of work abroad.
Common misconceptions
- Myth: A FAN can be issued without prior notice or opportunity to respond.
- Fact: The BIR must first notify the taxpayer of its findings through a Preliminary Assessment Notice, except in the cases listed in NIRC §228, such as mathematical errors or a discrepancy between tax withheld and tax remitted. The taxpayer must also be informed in writing of the law and facts behind the assessment, or the assessment is void.
- Myth: You have 60 days to appeal a FAN.
- Fact: The protest period is 30 days from receipt of the FAN (NIRC §228). Missing it makes the assessment final, executory and demandable, and the BIR may proceed with collection. The 60-day period in §228 is for submitting supporting documents after a protest is filed.
- Myth: Paying the FAN amount waives your right to appeal or claim a refund.
- Fact: Paying does not by itself waive your remedies. You may protest within 30 days of receipt, or pay and file a written claim for refund within two years from payment (NIRC §228, §229).
- Myth: A FAN is only issued for income tax deficiencies.
- Fact: A FAN can be issued for any tax deficiency: income tax, VAT, excise tax, estate tax, donor's tax, or other internal revenue taxes assessed by the BIR (NIRC §228). The procedure is the same regardless of tax type.
- Myth: The BIR must prove fraud or negligence to issue a FAN with penalties.
- Fact: The BIR may assess a 25% surcharge on unpaid tax without proving fraud (10% for micro and small taxpayers under RA 11976); the 50% surcharge requires willful neglect or a false or fraudulent return (NIRC §248). Interest at 12% per annum runs on unpaid tax from the due date (NIRC §249).
Questions people ask
What should I do immediately upon receiving a FAN?
Do not ignore it. Note the date of receipt, verify the contents, compute the total amount due (tax, surcharge and interest), and decide whether to protest or pay. If protesting, file a written request for reconsideration or reinvestigation with the office that issued the FAN within 30 days of receipt (NIRC §228; RR 12-99, as amended by RR 18-2013).
Can I request an extension of the 30-day appeal period?
The 30-day period is set by NIRC §228, which has no provision for extending it. If you miss it, the assessment becomes final, executory and demandable. An assessment issued without informing the taxpayer in writing of the law and facts it rests on is void (NIRC §228), and that defect can still be raised.
What happens if I do not appeal or pay within 30 days?
The assessment becomes final, executory and demandable. The BIR may then collect by distraint of personal property, including garnishment of bank deposits, by levy on real property, or by court action (NIRC §205 to §207). Interest at 12% a year (6% for micro and small taxpayers) keeps running on the unpaid amount until full payment (NIRC §249).
Can I appeal a FAN if I have already paid the amount?
Paying does not by itself waive your remedies. You may still protest within 30 days of receipt of the FAN, or pay and file a written claim for refund with the BIR within two years from payment (NIRC §228, §229).
What is the difference between a FAN and a Notice of Levy?
A FAN is the assessment; distraint and levy are the BIR's remedies to collect a delinquent tax by seizing personal or real property (NIRC §205 to §207). Courts cannot enjoin tax collection (NIRC §218), but during an appeal the Court of Tax Appeals may suspend collection if the taxpayer deposits the amount claimed or files a surety bond (RA 1125, Sec. 11, as amended).
Can I negotiate or settle a FAN with the BIR?
The Commissioner may compromise a tax where there is reasonable doubt about the validity of the assessment (minimum 40% of the basic tax) or a clear inability to pay (minimum 10%), with larger or lower settlements needing Evaluation Board approval (NIRC §204(A)). A compromise is a separate request from a protest, so the 30-day protest deadline still applies.
What documents should I attach to my appeal of a FAN?
Attach copies of all relevant documents, such as receipts, invoices, bank statements, contracts, correspondence with the BIR, and a detailed written explanation of why the assessment is incorrect. Organize documents and reference them in your protest letter. For a request for reinvestigation, all supporting documents must be submitted within 60 days from filing the protest, or the assessment becomes final (NIRC §228).
If the BIR denies my protest, what are my next steps?
You may appeal to the Court of Tax Appeals (CTA) within 30 days of receiving the denial, or within 30 days after the BIR fails to act within 180 days from submission of documents (NIRC §228). If the denial came from the Commissioner's authorized representative, the regulations also allow an administrative appeal to the Commissioner within 30 days instead (RR 12-99, as amended by RR 18-2013). CTA cases are governed by RA 1125, as amended.
In practice
- A FAN is typically issued with a Formal Letter of Demand after a BIR audit or investigation and after the taxpayer has had the chance to reply to the Preliminary Assessment Notice.
- Many taxpayers miss the 30-day appeal deadline because they do not understand the FAN or assume they can negotiate with the BIR after the deadline; this results in immediate collection action.
- Courts cannot enjoin the collection of taxes (NIRC §218), but once a case is on appeal the Court of Tax Appeals may suspend collection if the taxpayer deposits the amount or files a surety bond (RA 1125, Sec. 11, as amended).
- The CTA reviews disputed assessments on appeal from the BIR's decision on a protest, or from its inaction within 180 days from submission of documents; the taxpayer must first file a timely protest (NIRC §228).
- Large corporations and high-income individuals often engage tax counsel immediately upon receiving a FAN to ensure a timely, well-documented appeal and to explore settlement or compromise options with the BIR.
Next steps
Learn more
Tax Penalty Calculator
Interest On Deficiency Calculator
BIR Assessment Calculator
BIR Form 0605 Payment Form
BIR Form 1701 Annual Income Tax Return
BIR Form 2550Q Quarterly VAT Return
How To File A Tax Protest
BIR Collection Procedures Guide
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Sources & References (1)
Primary sources and the laws, regulations, and official issuances this page relies on. Links open the recorded source documents or references.
- LawPhil Project (Arellano Law Foundation). “NIRC §228 (FAN, 30-day protest): full text.” lawphil.net. NIRC of 1997 (RA 8424), Sec. 228. Source checked .