If you find that you have missed the deadline for filing P.N.D.94, the important thing is to file the late return as soon as possible so that the monthly surcharge stops accruing. P.N.D.94 is the half-year personal income tax return for people who have assessable income under Section 40(5) to (8) of the Revenue Code earned between 1 January and 30 June of the tax year. Although late filing carries a criminal fine and a statutory surcharge, a taxpayer who understands the steps, the documents required and the calculation method can settle the late tax correctly and keep unnecessary costs down.
Missed the P.N.D.94 deadline? What to do first
Once the half-year filing deadline has passed (normally 30 September for paper returns and 8 October each year for online filing through the Revenue Department e-Filing system), taxpayers should not leave it and wait to file everything together at year-end on P.N.D.90, because the surcharge keeps accumulating. The basic three-step approach is as follows:
- Gather income documents and withholding tax evidence: Summarise the assessable income under Section 40(5)-(8) actually received from 1 January to 30 June 2026, together with withholding tax certificates (Form 50 Bis) and evidence of actual expenses (if you choose to deduct actual expenses).
- Calculate the tax, the surcharge and the criminal fine: Work out net income and the tax payable at the personal income tax rates, then calculate the surcharge of 1.5% per month (a fraction of a month counts as one month) from the day after the deadline, and set aside the criminal fine under the Revenue Department's settlement rules.
- File the return and pay the back tax: Print Form P.N.D.94, fill it in completely and submit it together with the tax, fine and surcharge at the Area Revenue Branch Office where your business or residence is located (where the online system no longer accepts late returns for that tax period).
What is P.N.D.94 and why does the half-year filing matter?
Under Section 56 Bis of the Revenue Code, individuals, persons who die during the tax year, undivided estates, and ordinary partnerships or groups of persons that are not juristic persons who have assessable income under Section 40(5), (6), (7) and (8) in the first six months of the tax year (1 January – 30 June) above the statutory threshold must file P.N.D.94 between July and September of that tax year.
Who is required to file P.N.D.94 for 2026?
- Section 40(5) income: income from letting property, such as rental houses, land, commercial buildings, condominiums and cars
- Section 40(6) income: income from the six independent professions: medical practice, law, engineering, architecture, accounting and fine arts
- Section 40(7) income: income from contract work where the contractor must supply the essential materials other than tools
- Section 40(8) income: income from business, commerce, agriculture, industry, transport, sale of real estate, restaurants, cafes, hotels/homestays, online selling, and creators/influencers
Minimum income thresholds for filing:
- Single: combined income under Section 40(5)-(8) in the first half of the year above 60,000 baht
- Married: income under Section 40(5)-(8), whether from one spouse alone or combined, in the first half of the year above 120,000 baht
If your income reaches these thresholds, the law requires you to file P.N.D.94 even when the calculation shows no tax to pay. The half-year tax paid is treated as a tax credit that can be deducted in full from the year-end tax (P.N.D.90).
Missed the P.N.D.94 deadline: how much are the fine and surcharge?
A person who misses the P.N.D.94 deadline faces two additional charges under the Revenue Code: a criminal fine and a statutory surcharge:
1. Criminal fine for not filing on time (Section 35)
Section 35 of the Revenue Code sets a criminal fine of up to 2,000 baht for failing to file a return within the deadline, but the Revenue Department has settlement rules that scale the fine to how late the return is:
- Filed no more than 7 days late after the deadline: settlement fine of 100 baht
- Filed more than 7 days late after the deadline: settlement fine of 200 baht
- If an officer has issued a summons or warning letter: the fine may be settled at the maximum of 2,000 baht
2. Surcharge for late payment of tax (Section 27)
Under Section 27, anyone who does not pay tax within the deadline must pay a surcharge of 1.5% per month, or fraction of a month, of the tax payable, subject to these key conditions:
- It runs from the day after the last day of the filing deadline until the day the tax is paid in full
- A fraction of a month counts as a full month: even one day late is immediately charged as one month (1.5%)
- The surcharge cannot exceed the amount of tax payable for that period
| Item | Filed on time | Filed late (up to 7 days) | Filed late (more than 7 days) |
|---|---|---|---|
| Criminal fine (Section 35) | 0 baht | 100 baht | 200 baht (up to 2,000 baht) |
| Surcharge (Section 27) | None | 1.5% of the tax (a fraction of a month counts as 1 month) | 1.5% per month (calculated up to the actual payment date) |
| If the calculation shows no tax to pay | 0 baht | Criminal fine of 100 baht | Criminal fine of 200 baht |
How to file a late P.N.D.94 step by step
When you need to file P.N.D.94 late, you can follow the correct procedure as follows:
Step 1: Summarise half-year income and allowances
Gather the assessable income under Section 40(5)-(8) for 1 January – 30 June 2026 and choose the expense deduction method the law allows (actual expenses with complete supporting documents, or a flat-rate deduction, for example 60% for trading/services under Section 40(8)).
Rules for allowances on P.N.D.94 (half of the full-year entitlement):
- Taxpayer's personal allowance: 30,000 baht (full year 60,000 baht)
- Spouse allowance (spouse with no income): 30,000 baht (full year 60,000 baht)
- Child allowance: 15,000 baht per child (full year 30,000 baht per child)
- Parent allowance: 15,000 baht per parent (full year 30,000 baht per parent)
- Life / health insurance premiums: deductible at the amount actually paid in the first half of the year, up to 50,000 baht (half of the full-year ceiling of 100,000 baht)
Step 2: Complete Form P.N.D.94
Download Form P.N.D.94 from the Revenue Department website, then calculate the tax both ways and compare:
- Method 1 (progressive rates): take net income (income - expenses - allowances) and apply the tax rates of 5% to 35%
- Method 2 (minimum tax): if assessable income of all types combined is 120,000 baht or more in the first half of the year, calculate tax at 0.5% of assessable income before expenses (if the tax under Method 2 is no more than 5,000 baht, this method is waived and you pay under Method 1)
Step 3: File in person at the Area Revenue Branch Office
If the extended online filing window has closed, you must submit the documents yourself at the Area Revenue Branch Office. Prepare the following:
- Form P.N.D.94, fully completed and signed, 2 copies
- Original national ID card with a photocopy
- Original withholding tax certificates (Form 50 Bis) with copies (if any)
- Power of attorney with a 10 baht duty stamp (if an agent files on your behalf), with copies of the ID cards of both the grantor and the agent
- Cash, debit/credit card, or QR Payment to pay the tax, criminal fine and surcharge
Worked example of tax, fine and surcharge: a Chiang Mai business
Here is an example of the tax and penalties for a business owner in Chiang Mai who files after the deadline:
Case study: Khun Min runs a coffee shop and bakery in the Nimmanhaemin area, Mueang district, Chiang Mai (assessable income under Section 40(8)). She is single. In the first half of the year (1 Jan – 30 Jun 2026) her sales totalled 600,000 baht and she chose the 60% flat-rate expense deduction. Khun Min forgot to file P.N.D.94 and went to file it two full months after the deadline.
Step 1: Calculate the half-year income tax
- Assessable income under Section 40(8): 600,000 baht
- Less 60% flat-rate expenses: 360,000 baht (leaving 240,000 baht)
- Less half-year personal allowance: 30,000 baht
- Net income: 210,000 baht
Step 2: Calculate tax at progressive rates and compare with the 0.5% method
- Method 1 (progressive rates):
- First 0 – 150,000 baht of net income: tax rate 0% = 0 baht
- Net income 150,001 – 210,000 baht (60,000 baht x 5%): = 3,000 baht
- Tax under Method 1 = 3,000 baht
- Method 2 (0.5% minimum tax): 600,000 x 0.5% = 3,000 baht (because the tax under Method 2 does not exceed 5,000 baht, the law waives it, so tax is paid under Method 1)
- Tax payable: 3,000 baht
Step 3: Calculate the criminal fine and surcharge for filing 2 months late
- Criminal fine (Section 35, more than 7 days): 200 baht
- Surcharge (Section 27, 1.5% x 2 months): 3,000 x 1.5% x 2 = 90 baht
- Total payable on the filing date: 3,000 + 200 + 90 = 3,290 baht
Once Khun Min has paid, she receives a receipt from the Revenue Department. The 3,000 baht of tax (excluding the fine and surcharge) can be entered as a tax credit against the year-end tax on P.N.D.90.
Common mistakes and advice from Chiang Mai accounting specialists
From our experience advising and providing full-service bookkeeping and accounting to hotel, cafe and retail businesses in Chiang Mai, these are the key mistakes we see most often with P.N.D.94:
- Assuming a loss-making business does not need to file: the P.N.D.94 filing test is based on "assessable income before expenses", not net profit. If a single person has total income above 60,000 baht in the first half of the year, they must file even if costs are so high that the business made a loss.
- Deducting the full-year allowances in full: the half-year return may use only "half" of the allowances. Entering the full-year amounts understates the tax, and the shortfall attracts the 1.5% per month surcharge.
- Assuming you can wait and file everything on P.N.D.90 at year-end without consequence: filing P.N.D.90 does not cancel the criminal liability and surcharge for P.N.D.94. If the Revenue Department audits later, it will issue an assessment for the criminal fine and the surcharge running from the P.N.D.94 deadline until the date of full payment.
- No system for documenting actual costs: businesses whose cost of goods is higher than the 60% flat rate often lose tax savings because they lack proper tax invoices or receipts. Keeping income and expense records and planning personal and corporate tax systematically from the start of the year lets you choose the actual-expense deduction and save tax lawfully.
Frequently asked questions about filing P.N.D.94
If the tax works out to 0 baht but I missed the P.N.D.94 deadline, is there still a fine?
Yes. You must pay the criminal fine under Section 35 of 100 baht (up to 7 days late) or 200 baht (more than 7 days late) for not filing within the deadline, but no surcharge under Section 27 applies because there is no tax base to pay.
When is the P.N.D.94 filing deadline for 2026?
Paper filing at the Area Revenue Branch Office closes on 30 September 2026. Online filing through the Revenue Department e-Filing system gets an extra 8 days and closes on 8 October 2026.
If e-Filing has closed for that period, can I still file late online?
Generally, once the extended online filing deadline has passed, the e-Filing system stops accepting returns for that tax period. You must print and complete Form P.N.D.94 and submit it, with payment of the fine, to an officer at the Area Revenue Branch Office only.
If I have never filed P.N.D.94 but file P.N.D.90 every year-end, how far back can the Revenue Department audit?
The Revenue Department has the power to assess tax and collect penalties and surcharges under the Revenue Code. The audit period under Section 19 is 2 years (extendable to a maximum of 5 years where there are reasonable grounds to suspect intentional tax evasion), and under the Civil and Commercial Code the limitation period for claiming unpaid tax debt is up to 10 years.
Summary: managing half-year tax professionally
A missed P.N.D.94 deadline should be fixed as soon as you realise it, to stop the 1.5% per month surcharge from building up. Preparing the documents and calculating the figures correctly before meeting the revenue officer helps the late filing go through quickly and correctly.
For business owners, shop owners and freelancers who want someone to look after their accounts and taxes properly, without worrying about missed filings or back penalties, the Chiang Mai accounting team at YMTD Accounting Partner is ready to act as your adviser, handling tax and setting up a complete digital document system.
Contact YMTD Accounting Partner, Chiang Mai
Phone: 081-542-3019
LINE Official: @premwittawat
