Frequently Asked Questions & Mistakes to Avoid in Business

Part 1: Frequently Asked Questions (FAQ)

Business registration

Do you need to register your business to sell online?

Answer: It depends on the scale.

Situation	Registration required?
Selling goods in small, infrequent quantities.	Optional
Regular business operations with a fixed location.	Registration required.

Note: While business registration is not mandatory, you must still register for tax purposes if you have taxable income.

Where do I register my business?

Reply:

Online: National Public Service Portal (dangkykinhdoanh.gov.vn) (Primarily for Businesses)
Offline: District/County Finance and Planning Department where the business is located.

Processing time: 3-5 business days.

Do sole proprietorships need an accountant?

Answer: Not required:

Household businesses are not required to have an accountant, but they are required to keep complete accounting records.
The accountant can be the head of the household, a family member, or an outsourced person.
No accounting degree required.

Taxes and revenue

At what revenue level is tax payable?

Reply:

Annual Revenue	VAT	Personal Income Tax
≤ 500 million	No	No
> 500 million	Must pay	Must pay

Calculation formula:

 Thuế GTGT = Doanh thu × Tỷ lệ thuế GTGT (1-5%) Thuế TNCN = Doanh thu × Tỷ lệ thuế TNCN (0.5-5%) Who pays the taxes when selling on Shopee and Lazada? Thuế GTGT = Doanh thu × Tỷ lệ thuế GTGT (1-5%) Thuế TNCN = Doanh thu × Tỷ lệ thuế TNCN (0.5-5%)

Answer: E-commerce platforms are obligated to deduct VAT and personal income tax and pay them on behalf of the seller.

Note: E-commerce platforms may provide revenue data to tax authorities, so you need to declare it accurately.

What is the retail tax rate for goods?

Reply:

VAT: 1%
Personal income tax: 0.5%

Example: Revenue of 500 million/year

VAT = 500 million × 1% = 5 million
Personal income tax = 500 million × 0.5% = 2.5 million
Total tax = 7.5 million VND

Does taxable revenue include discounts and promotions?

Answer: Taxable revenue = Actual revenue (after deducting discounts and price reductions).

For example:

Original price: 1 million
20% discount: -200,000
Taxable revenue: 800,000 VND

Do you have to pay taxes when selling goods at a loss?

Answer: You may still have to pay if the tax is calculated based on revenue (without deducting expenses).

If you want to calculate taxes based on actual income (revenue - expenses), you need:

Register the declaration method.
There are complete records and documents.
Proof of legitimate expenses

Electronic invoices

When is it mandatory to issue electronic invoices?

Reply:

Households/individuals declaring taxes must use electronic invoices.
Special case: The tax authority issues invoices on a per-transaction basis.

What should be done if an invoice is issued incorrectly?

Answer: It depends on when it is detected.

Time	How to handle it
Not yet shipped to the buyer.	Cancel the invoice, reissue it.
Submitted, tax not yet declared.	Issue a replacement invoice.
Taxes have been filed.	Issue an adjustment invoice.

Note: Replacement/amendment invoices must clearly state "Replacement/Amendment for invoice number... dated..."

What about retail customers who don't need a receipt?

Answer: You still have to:

Record the revenue in the books.
File your taxes fully.
A daily invoice can be issued for total retail sales revenue (write "Individual Customer" in the buyer section).

Do electronic invoices need to be printed out?

Answer: Not mandatory. Electronic invoices have the same legal validity as paper invoices. Printing is only necessary upon customer request or for internal record-keeping.

Declare and pay taxes

Should taxes be filed monthly or quarterly?

Reply:

Condition	Filing period
VAT payable < 50 million/year	By quarter
Value Added Tax (VAT) payable ≥ 50 million VND/year	By month
Newly established households	By quarter (first year)

What are the deadlines for filing tax returns and paying taxes?

Reply:

Filing period	Deadline for submitting the declaration	Payment deadline
Month	The 20th of next month	Along with the declaration form
Dear	The 30th day of the first month of the following quarter	Along with the declaration form
Year (final settlement)	March 31st of next year	Along with the declaration form

Note: Late payments will incur a late payment penalty of 0.03% per day × the amount of the late payment.

Is it possible to file online?

Answer: Yes, in two ways:

HTKK + Electronic Tax Portal: Prepare tax returns offline, submit online.
Direct declaration: Go to thuedientu.gdt.gov.vn, declare and submit immediately.

Requirement: A digital signature (USB Token) is required to sign and submit the declaration.

Do I need to declare revenue if I have no revenue during the period?

Answer: Yes. If you are a household taxpayer, you still have to submit form 0 (the form with revenue = 0).

Expenses and deductions

Which expenses are deductible when calculating taxes?

Answer: 7 main types of costs:

Renting premises
Labor
Electricity
Water
Telecommunications (Internet, telephone)
Management and sales (office supplies, depreciation, etc.)
Other costs (shipping, advertising, etc.)

Requirements: Must have invoices/receipts that are directly related to business.

Can purchases made without a receipt be deducted from the cost?

Answer: The principle is: No receipt = No deduction.

Exception: In some cases, a replacement list is prepared:

Buy agricultural products from farmers.
Hiring seasonal workers
Buy ingredients in small quantities from the market.

Can cash payments be deducted from expenses?

Reply:

Transactions ≤ 20 million: Approved
Transactions exceeding 20 million VND: Payment must be made via bank transfer to be eligible for deduction.

How do you calculate electricity and water costs when running a home-based business?

Answer: It must be allocated according to a reasonable proportion:

By area: Business area / Total area
By capacity: Total capacity of business equipment

Example: A 100m² house, using 30m² as a shop → Electricity cost for business = 30% × Total electricity bill.

Hire staff

Is personal income tax deductible when hiring employees?

Answer: It depends on the type of contract and salary.

Type of contract	Income level	Deduction?
Employment contract ≥ 3 months	≤ 11 million/month	Are not
Employment contract ≥ 3 months	> 11 million/month	Yes (5-35%)
Employment contract less than 3 months	≤ 2 million/time	Are not
Employment contract less than 3 months	> 2 million/time	There is (10%)

Are salaries paid to family members considered deductible expenses?

Answer: Yes , if:

There is an employment contract (or service contract).
There are time sheets and payroll records.
There is a payment voucher.
A reasonable salary for the job.

Note: Personal income tax must still be deducted if eligible.

If an employee quits in the middle of the year, who will handle their personal income tax settlement?

Reply:

If the employee gets a new job: The new company will settle the accounts (if authorized).
If the employee does not have a new job: The employee will settle their tax obligations themselves at the tax office.

HTKK software

Is HTKK free?

Answer: Yes. HTKK is free software provided by the General Department of Taxation.

Download: www.gdt.gov.vn → Search for the "HTKK" banner

Can HTKK be installed on a Mac?

Answer: Not directly. HTKK only runs on Windows. If you're using a Mac, you can:

Install Windows via Boot Camp or a virtual machine (Parallels, VMware).
Declare directly on the website: thuedientu.gdt.gov.vn

What should I do if I forget my online tax account password?

Reply:

Visit thuedientu.gdt.gov.vn
Click "Forgot password"
Enter your tax identification number and registered email address.
Follow the instructions to reset your password.

If that doesn't work, contact the local Tax Office for assistance.

Part 2: Common Mistakes to Avoid

Mistakes in business registration

No.	Mistake	Consequence	How to avoid
1	Thinking that selling online doesn't require registration.	Administrative penalties and tax arrears collection.	Register when your revenue exceeds 100 million VND/year.
2	Incorrect business address registration	Invalid license	Use your actual business address.
3	Not updated when changes occur.	Incorrect information makes it difficult to issue invoices.	Notice changes within 10 days.

Mistakes regarding taxes and revenue

No.	Mistake	Consequence	How to avoid
1	Failure to declare revenue from e-commerce platforms.	Tax arrears + penalties (data reported to the tax authority)	Declare all sources of income in full.
2	Incorrect revenue threshold calculation.	Applying the wrong tax rate.	Summarize revenue from all sources.
3	Choosing the wrong profession (tax rate)	Overpaying or underpaying taxes	Confirm with the Tax Department.
4	Tax is calculated on the original price (without deducting any discounts).	Overpaying taxes	Based on actual revenue
5	Do not declare when there is no revenue.	Fined for not submitting the tax return.	Submit form number 0

Billing errors

No.	Mistake	Consequence	How to avoid
1	Do not keep purchase receipts.	The cost could not be proven.	Keep all invoices for at least 5 years.
2	Incorrect invoices were issued but not processed.	Invalid invoice	Issue a replacement/adjustment invoice.
3	Issue an invoice before delivery.	Violation of regulations	Issue an invoice upon completion of the transaction.
4	No invoices will be issued upon customer request.	Being fined, losing reputation.	Invoices issued upon request.
5	Delete/cancel invoices already sent to customers.	Serious violation	Issue a replacement/adjustment invoice.

Tax filing errors

No.	Mistake	Consequence	How to avoid
1	Submitting the tax return late	Fines ranging from 2 to 25 million VND.	Set reminders in advance of deadlines.
2	I submitted the tax return but forgot to pay.	Late payment fee: 0.03% per day	Pay immediately after submitting the declaration.
3	Incorrect filing period selected (month/quarter)	The application was rejected.	Check carefully before submitting.
4	No electronic receipts are kept.	Difficult to prove submission	Keep the receipt immediately after submission.
5	Use the old version of HTKK.	The application was rejected.	Update HTKK regularly.

Cost mistake

No.	Mistake	Consequence	How to avoid
1	Payment of over 20 million in cash.	Non-deductible expenses	Transfer for large transactions
2	Incorporate personal expenses into business operations.	Failing the test may result in a penalty.	Separate personal and business expenses.
3	Incorrect depreciation of assets.	Disallowed expenses	According to regulations of the Ministry of Finance
4	No allocation of shared costs.	Costs disqualified during inspection.	Allocation according to a reasonable ratio.
5	Purchases made without a receipt.	No deductions allowed.	Always ask for a receipt.

Mistakes regarding employees

No.	Mistake	Consequence	How to avoid
1	No personal income tax deduction when needed.	Subject to back taxes and penalties.	Check the deduction conditions.
2	Tax deductions were made but not declared.	Administrative penalties	Submit tax returns monthly/quarterly.
3	Forget about year-end settlement.	Employees are not eligible for tax refunds.	Submit your tax return before March 31st.
4	No employment contract signed.	Legal risks, difficulty in calculating costs.	Sign contracts with all employees.
5	Paying wages without receipts.	Unrecognized expenses	Keep payroll records and payment vouchers.

Mistakes in overall management

No.	Mistake	Consequence	How to avoid
1	Do not separate personal and business accounts.	Difficult to manage, difficult to account for.	Open your own bank account.
2	No record keeping	Not knowing the actual profit/loss.	Keep a daily record or use software.
3	Policy changes are not being updated.	Misapplication of regulations	Monitor information from the tax authorities.
4	Unauthorized alteration of tax records	Violation of the law	Prepare official supplementary/amendment documents.
5	Failure to retain records for the required period.	No evidence found upon examination.	Store for at least 5-10 years

Checklist: Self-check for tax compliance

Monthly

Summarize revenue from all sources.
Store purchase invoices
Calculate salaries and deduct personal income tax (if applicable).
Record expenses in the accounting books.

Quarterly

Submit VAT and personal income tax returns (before the 30th of the first month of the following quarter).
Pay taxes (within the same deadline)
Check your tax debt status at thuedientu.gdt.gov.vn

End of the year

Finalize personal income tax for employees (before March 31st)
Review all invoices and supporting documents.
Back up accounting data.
Update to the latest version of HTKK.

When should you seek expert advice?

You should contact an accountant/tax consultant when:

Revenue exceeds 1 billion VND/year.
There are import and export transactions.
There are multiple branches/business locations.
Asked to provide an explanation by the tax authorities.
We want to transform into a company.

Contact support

General Department of Taxation Hotline: 1900 6199
Website: www.gdt.gov.vn
Electronic tax portal: thuedientu.gdt.gov.vn
Local Tax Office: Search by your district/county

Conclude

From 2026, online businesses and small businesses will enter a phase of stricter management, based on actual revenue and interconnected data from e-commerce platforms, banks, and electronic invoices. Many old concepts such as the 100 million VND threshold or flat-rate tax will no longer apply. Instead, sellers need to clearly understand their obligations to declare, record, and correctly distinguish the portion of revenue that has been tax-deducted by the platform. Misunderstanding regulations or applying outdated laws can lead to incorrect declarations, tax arrears, and penalties. Systematically managing revenue, expenses, invoices, and personnel from the outset is key to sustainable business and legal compliance in this new phase. GTG CRM helps you manage revenue, expenses, invoices, and employees in a single system – minimizing errors and ensuring tax compliance. Try it for free.