When a business entity uses goods or services in a trade for the goods or services of others, the sales amount shall be the higher of the prevailing prices for the goods or services traded-out and traded-in.

The sales amount in the circumstances of deemed sales of goods as specified in Paragraph 3 of Article 3 of the Act shall be determined as follows:
1. Under Subparagraphs 1 and 2: the current price of goods.
2. Under Subparagraphs 3 to 5: for purchasing goods on behalf of a third party, the actual price of the goods purchased; for requesting a third party to sell goods and for selling goods on behalf of a third party, the agreed sales price of the consigned goods.
The business entity undertaking sales or purchases referred to in Subparagraph 2 above shall prepare written agreements for verification.
The provisions of the preceding two Paragraphs shall also be applicable to the deemed sale of services as prescribed in Paragraph 4 of Article 3 of the Act.

Where a business entity sells goods by an installment method, the price stipulated to be received in each installment shall be the sales amount, unless it is stipulated that, at the time of the collection of the first installment, the entire price receivable is to be defined as the sales amount.

Where a business entity sells a parcel of land together with building fixed on the land, unless the selling price for the land and that for the building are stated separately, the sales amount for the building shall be calculated based on the ratio of the assessed standard price of the unit of the building (inclusive of business tax) to the total of the government-assessed current value of the land and the assessed standard price of the unit of the building (inclusive of business tax). The formula for calculation is as follows:
Selling price of the building =

　　　　　　　　　　　　　　Assessed standard price of the unit of
　　　　　　　　　　　　　　the building × (1 + Applicable tax rate)
Selling price of
the land and building × ─────────────────────────
　　　　　　　　　　　　　　Government-assessed current value of
　　　　　　　　　　　　　　the land + Assessed standard price of
　　　　　　　　　　　　　　the unit of the building × (1 +
　　　　　　　　　　　　　　Applicable tax rate)

Sales amount of the building = Selling price of the building ÷ (1 + Applicable tax rate)

Where a business entity issues government uniform invoices before it makes delivery of the goods or before it renders services, the amount in the issued government uniform invoices shall be treated as its sales amount.

The incentive bonus earned or paid by a business entity in accordance with a sales contract shall be treated as purchase or sales discount, respectively.

With respect to a business entity subject to business tax calculation under Section 1 of Chapter 4 of the Act, the sales amount for security deposits it receives from the leasing out of property shall be calculated on a monthly basis, provided that for any term of lease of less than a full month, the sales amount need not be calculated. The formula for calculation is as follows:
Sales amount＝

　　　　　　　　　　　　Fixed interest rate for a one-year postal time
　　　　　　　　　　　　deposit as announced on 1 January of the lease
　　　　　　　　　　　　year ÷ 12
Security deposit × ─────────────────────────────
　　　　　　　　　　　　　　　　　1 ＋Applicable tax rate

With respect to a business entity subject to calculation of business tax under Section 2 of Chapter 4 of the Act, the sales amount for security deposits it receives from the leasing out of property shall be calculated on a monthly basis, provided that for any term of lease of less than a full month, the sales amount need not be calculated. The formula for calculation is as follows:
Sales amount = Security deposit × Fixed interest rate for a one-year postal time deposit as announced on 1 January of the lease year ÷12

The term "current price" as used in the Act refers to the current market price prevailing in the locality for the sale of the same goods or services.

Goods or services for entertainment purposes referred to in Subparagraph 3 of Paragraph 1 of Article 19 of the Act shall include the entertainment of guests at a banquet and gifts which have nothing to do with the promotion of business.
The term "passenger car for personal use" as used in Subparagraph 5 of Paragraph 1 of Article 19 of the Act refers to a passenger automobile having not more than nine seats and which is not used for the sale of goods or rendering of services.

Where the personal effects brought in by passengers entering into the territory of the ROC exceed the duty-exemption limit, the excess shall be subject to business tax to be calculated, in accordance with Article 20 of the Act, on the duty-paid value determined based on “The Rules Governing the Declaration, Examination, Duty Payment, and Release of Personal Effects Carried by Incoming Passengers”.

Where the value of an imported postal parcel exceeds the limit for the exemption of duty set out in “Regulations Governing Customs Clearance Procedures for the Import and Export of Postal Parcels”, a business tax shall be imposed at the full amount of the value of the duty to be paid upon importation in accordance with Article 20 of the Act.

(Deleted)

In the event a business entity subject to calculation of business tax under Section 1 of Chapter 4 of the Act fails to submit the input tax vouchers for deduction from the output tax in the current reporting period, it may defer submission of the vouchers until the following reporting period. If the business entity still fails to do so in the following reporting period, it shall, in the reporting period when it actually submits the vouchers for deduction from the output tax, specify the reasons. However, the time period for submission of the input tax vouchers for deduction from the output tax shall be limited to ten years.

A deduction copy of the uniform invoice marked with the words "Remedial Issuance for Tax Evasion" may not be used as a voucher for deduction from the output tax or for reduction of the assessed tax. However, this requirement does not apply if the remedial uniform invoice is issued as a result of a report from the purchaser.
If any of the following circumstances exists, the supplemental business tax collected by Customs may not be reported for deduction from the output tax:
1. When a business entity importing goods is found to have under-reported the duty-paid value of the imported goods under any of the circumstances set out in the subparagraphs of Paragraph 1 of Article 51 of the Act.
2. Where a bonded zone business entity, a duty-free shop administered by Customs, or a duty-free shop on an offshore island takes inventory of its bonded goods and the quantity of the actual inventory is less than the quantity of the ending book inventory.

Where a business entity, whose business tax is determined by the tax authority in charge as prescribed in Article 23 of the Act, has documents supporting the purchases stated in Paragraph 1 of Article 19 of the Act, the tax paid on such purchases cannot be credited based on Article 25 of the Act.

Where a business entity applies, based on article 23 and paragraph 1 of Article 24 of the Act, for changing the method of calculating its business tax into the one provided in Section I of Chapter IV of the Act, a decision shall be made by the tax authority in charge within one month. Such business entity shall use government uniform invoices, set up books of accounts from the first day of the month in which approval of change is granted by the tax authority in charge, and file business tax returns and pay the tax in accordance with the reporting period specified in Article 35 of the Act.
The creditable tax on goods or services purchased, as prescribed in Paragraph 2 of Article 25 of the Act, which is unused before the change mentioned in the preceding Paragraph is made may be claimed against the business tax payable after the change is made.
The preceding two Paragraph shall be applicable mutatis mutandis to those small-scale enterprises which are determined by the Ministry of Finance as having to calculate their business tax in accordance with Section I of Chapter IV of the Act.

Where a business entity subject to calculation of business tax under Section 1 of Chapter 4 of the Act sells goods or services to a non-business entity and issues a uniform invoice pursuant to the latter part of Paragraph 3 of Article 32 of theAct, the formula for calculation of the sales amount and output tax to be reported in accordance with Article 35 of the Act is as follows:
Output tax = Total amount of the uniform invoices issued in the current reporting period ÷ (1 + Applicable tax rate) x Applicable tax rate
Sales amount =Total amount of the uniform invoices issued in the current reporting period – Output tax
The output tax referred to in the preceding paragraph shall be rounded to the nearest New Taiwan Dollar.

A business entity specified in Subparagraph 4 of Article 6 of the Act selling electronic services in foreign currency shall convert the foreign currency into New Taiwan Dollar at the closing spot buying exchange rate announced by the Bank of Taiwan on the following dates when it files a tax return for its sales amount and tax payable or overpaid in accordance with Article 35 of the Act:
1. The last day of the taxable period.
2. Where a business entity encounters a merger, ownership transfer, dissolution, or nullification of business, the last day of the prior taxable period of any of these events.
A business entity specified in Subparagraph 4 of Article 6 of the Act, who pays business tax by remittance, shall bear remittance charges and relevant service fees and remit the tax computed in accordance with the preceding paragraph to the designated public treasury.
Regarding the closing exchange rate posted by the Bank of Taiwan specified in Paragraph 1, if the spot-buying exchange rate is unavailable, a business entity shall convert the foreign currency into New Taiwan Dollar with the cash-buying exchange rate instead.
If the last day of a period specified in Paragraph 1 falls on Sunday, national holiday, or any other holiday, the last day shall be the day following that day instead, and if the last day of a period specified in Paragraph 1 falls on Saturday, the last day shall be the Monday of the following week instead.

Where a business entity which files its tax returns under Article 35 of the Act goes into merger, undergoes transfer of ownership, dissolution or winding-up, it shall apply, within fifteen days after the occurrence of the event, to the competent tax authority for checking and approval of a tax return for the current reporting period together with a detailed list of uniform invoices issued and the documents supporting the refundable or creditable tax. If there is any business tax payable, it shall be paid to the public treasury beforehand, with the payment receipt attached to the return.
Where a business entity whose business tax is determined by the competent tax authority based on Articles 21 to 23 of the Act goes into merger, undergoes transfer of ownership, dissolution or winding-up, it shall apply to the competent tax authority, within fifteen days after the occurrence of the event, for determination of its business tax payable. Where the business entity's business tax is determined by the competent tax authority based on Article 23 of the Act and where it has input vouchers supporting its tax paid on purchases of goods or services for the current period, such input vouchers shall be attached.

Where a business entity, which computes its business tax based on the provisions of Section I of Chapter IV of the Act, is in the process of liquidation due to dissolution or nullification of business and has to dispose of its unsold goods or services, it shall still be required to apply to the tax collection authority for use of uniform invoices and shall declare the amount of business tax payable or over-paid in accordance with Article 35 of the Act.
Where a business entity has sales and business tax payable or over-paid during the liquidation period, it shall file a business tax return with the tax authority in charge within fifteen days from the date on which the liquidation period expires for payment or refund of the business tax.
The expiration date of the liquidation period mentioned in the preceding two Paragraphs for the company organization shall be in accordance with the Company Act; for the limited partnership organization shall be in accordance with the Limited Partnership Act; and for others shall be three months from the date of dissolution or nullification.
Where a business entity fails to report its business tax payable in accordance with Paragraphs 1 and 2 of this Article, the tax authority in charge shall determine its amount of sales and tax payable and collect the tax in accordance with Article 43 of the Act.

Inventory losses or casualty losses on goods, raw materials and supplies, work-in-process, semi-finished products and finished goods shall be allowed if such losses have been reported to and approved by the competent tax authority.